To see the other types of publications on this topic, follow the link: Phosphates.
Journal articles on the topic 'Phosphates'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Phosphates.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Nignan, Iliassou, Jean Ouedraogo, Satoshi Nakamura, Idriss Serme, and Kalifa Coulibaly. "Effets du mode d’application d’engrais phosphatés (CBKCa et TSP) sur la productivité du mil (Pennisetum glaucum (L.) R. Br) au centre ouest du Burkina Faso." International Journal of Biological and Chemical Sciences 17, no. 6 (January 18, 2024): 2312–24. http://dx.doi.org/10.4314/ijbcs.v17i6.14.
Full textAbstract:
La distance d’application des phosphatés pourrait influencer la réponse des cultures à la fertilisation phosphatée due à la faible mobilité du phosphore. Ainsi, une étude a été conduite en 2021 et 2022 à Saria, pour évaluer l’effet de la distance d’application de deux engrais phosphatés sur la productivité du mil. Se sont le Burkina Phosphate calciné enrichi en calcium (CBKCa) et triple super phosphate (TSP). Pour ce faire, un dispositif factoriel avec quatre répétitions a été installé. Les phosphates ont été appliquées sur les parcelles principales à trois distances d’application (0 ; 5 et 10 cm du collet du mil), sur les parcelles secondaires. 23 kg P2O5.ha-1 de ces engrais a été appliqués en combinaison avec du NKSB (37-14-6-1). Les résultats ont montré que quelle que soit l’année et indépendamment de la distance, le CBKCa et le TSP ont enregistré des valeurs moyennes identiques concernant les paramètres de croissance et la production de biomasse. L’application des phosphates, à 5 cm, a entraîné une augmentation significative du rendement en grain de 42% et 35% en 2021 par rapport à l’apport à 10 et 0 cm. En 2022, ces augmentations étaient de 111% et 33%. L’application de CBKCa à 5 cm pourrait être recommandée.
The distance of application of phosphates could influence the response of crops to phosphate fertilization due to the low mobility of phosphorus. Thus, a study was conducted in 2021 and 2022 in Saria, to evaluate the effect of the distance of application of two phosphate fertilizers on millet productivity. These are Burkina Calcined Phosphate enriched with calcium (CBKCa) and triple super phosphate (TSP). To do this, a factorial design with four repetitions was installed. The phosphates were applied to the main plots at three application distances (0, 5 and 10 cm from the millet collar), to the secondary plots. 23 kg P2O5.ha-1 of these fertilizers was applied in combination with NKSB (37-14-6-1). The results showed that whatever the year and independently of the distance, CBKCa and TSP recorded identical average values regarding growth parameters and biomass production. The application of phosphates, at 5 cm, led to a significant increase in grain yield of 42% and 35% in 2021 compared to the application at 10 and 0 cm. In 2022, these increases were 111% and 33%. Application of CBKCa at 5 cm could be recommended.
2
Wolschendorf, Frank, Maysa Mahfoud, and Michael Niederweis. "Porins Are Required for Uptake of Phosphates by Mycobacterium smegmatis." Journal of Bacteriology 189, no. 6 (January 5, 2007): 2435–42. http://dx.doi.org/10.1128/jb.01600-06.
Full textAbstract:
ABSTRACT Phosphorus is an essential nutrient, but how phosphates cross the mycobacterial cell wall is unknown. Phosphatase activity in whole cells of Mycobacterium smegmatis was significantly lower than that in lysed cells, indicating that access to the substrate was restricted. The loss of the outer membrane (OM) porin MspA also reduced the phosphatase activity in whole cells compared to that in lysed cells. A similar result was obtained for M. smegmatis that overexpressed endogenous alkaline phosphatase, indicating that PhoA is not a surface protein, contrary to a previous report. The uptake of phosphate by a mutant lacking the porins MspA and MspC was twofold lower than that by wild-type M. smegmatis. Strikingly, the loss of these porins resulted in a severe growth defect of M. smegmatis on low-phosphate plates. We concluded that the OM of M. smegmatis represents a permeability barrier for phosphates and that Msp porins are the only OM channels for the diffusion of phosphate in M. smegmatis. However, phosphate diffusion through Msp pores is rather inefficient as shown by the 10-fold lower permeability of M. smegmatis for phosphate compared to that for glucose. This is likely due to the negative charges in the constriction zone of Msp porins. The phosphatase activity in whole cells of Mycobacterium bovis BCG was significantly less than that in lysed cells, indicating a similar uptake pathway for phosphates in slow-growing mycobacteria. However, porins that could mediate the diffusion of phosphates across the OM of M. bovis BCG and Mycobacterium tuberculosis are unknown.
3
Asenjo, Ana, Lorena Rodríguez, and Nieves Villanueva. "Determination of phosphorylated residues from human respiratory syncytial virus P protein that are dynamically dephosphorylated by cellular phosphatases: a possible role for serine 54." Journal of General Virology 86, no. 4 (April 1, 2005): 1109–20. http://dx.doi.org/10.1099/vir.0.80692-0.
Full textAbstract:
The 241 aa human respiratory synctyial virus (HRSV) Long strain P protein is phosphorylated at serines 116, 117 and/or 119, and 232. Phosphates added to these residues have slow turnover and can be detected in the absence of protein phosphatase inhibition. Inhibition of phosphatases PP1 and PP2A increases the level of phosphorylation at serines 116, 117 and/or 119, suggesting a more rapid turnover for phosphates added to these residues compared to that of S232. High-turnover phosphorylation is detected in the P-protein NH2-terminal region, mainly at S54 and, to a lesser extent, at S39, in the Long strain. When the P protein bears the T46I substitution (in the remaining HRSV strains), phosphates are added to S30, S39, S45 and S54. Phosphatase PP1 removes phosphate at residues in the central part of the P-protein molecule, whereas those in the NH2-terminal region are removed by phosphatase PP2A. The significance of the phosphorylation of the NH2-terminal region residues for some P-protein functions was studied. The results indicated that this modification is not essential for P-protein oligomerization or for its role in viral RNA synthesis. Nonetheless, dephosphorylation at S54 could facilitate P–M protein interactions that probably occur during the egress of viral particles.
4
Jamroz, Dorota, Agnieszka Gajda-Janiak, Zbigniew Wzorek, Zygmunt Kowalski, and Janusz Kubizna. "Chemical and Biological Characteristics of Different Hydrated Monocalcium Phosphates for Broiler Chickens." Annals of Animal Science 12, no. 2 (March 1, 2012): 187–200. http://dx.doi.org/10.2478/v10220-012-0016-4.
Full textAbstract:
Chemical and Biological Characteristics of Different Hydrated Monocalcium Phosphates for Broiler ChickensThree hydrated monocalcium phosphates differing in purity (with or without monetite, or monetite and calcite) and in crystalline structure were used in broiler chickens diets. The performance indices, concentration of Ca, P and Mg and activity of alkaline phosphatase in blood plasma, the content of these mineral elements in bones, and physico-mechanical parameters of femur and tibia bones were recorded. Body weight on 35th day of life, feed intake and mechanical parameters of bone quality were slightly affected by the type of phosphates used. Higher Ca and P concentration in blood was stated in chickens fed diets with greater purity of phosphates, but activity of alkaline phosphatase has increased with the admixture of monetite or calcite used in phosphates. The best parameters of bone quality were found in the treatment in which hydrated monocalcium phosphate (MCP) with admixture of monetite and calcite was applied. Higher concentration of both Ca and Mg in bone was determined in chickens fed diets with pure phosphates.
5
de Groot, H., H. de Groot, and T. Noll. "Enzymic determination of inorganic phosphates, organic phosphates and phosphate-liberating enzymes by use of nucleoside phosphorylase-xanthine oxidase (dehydrogenase)-coupled reactions." Biochemical Journal 230, no. 1 (August 15, 1985): 255–60. http://dx.doi.org/10.1042/bj2300255.
Full textAbstract:
Coupled enzyme assays are described for measuring inorganic phosphates, organic phosphates and phosphate-liberating enzymes in biological material. The assays all determine Pi by its reaction with inosine, catalysed by nucleoside phosphorylase; this yields ribose 1-phosphate and hypoxanthine. The hypoxanthine is oxidized to uric acid by xanthine oxidase, and may be measured either by the absorbance of the uric acid, or by the formazan formed when a tetrazolium salt is used as the oxidant. The coupled enzyme assays are characterized by high sensitivity, quantitative utilization of phosphates and stoichiometric formation of the measurable products, measurement at pH 6.0-8.5, determination of phosphates within a single analytical step, and continuous measurement of phosphohydrolase activity in a corresponding rate assay. Examples include determinations of substrates such as Pi, PPi and AMP, and of enzymes such as 5′-nucleotidase, inorganic pyrophosphatase and glucose-6-phosphatase. Directions for further examples are given.
6
Tang, Xiaoyun, and David N. Brindley. "Lipid Phosphate Phosphatases and Cancer." Biomolecules 10, no. 9 (September 2, 2020): 1263. http://dx.doi.org/10.3390/biom10091263.
Full textAbstract:
Lipid phosphate phosphatases (LPPs) are a group of three enzymes (LPP1–3) that belong to a phospholipid phosphatase (PLPP) family. The LPPs dephosphorylate a wide spectrum of bioactive lipid phosphates, among which lysophosphatidate (LPA) and sphingosine 1-phosphate (S1P) are two important extracellular signaling molecules. The LPPs are integral membrane proteins, which are localized on plasma membranes and intracellular membranes, including the endoplasmic reticulum and Golgi network. LPPs regulate signaling transduction in cancer cells and demonstrate different effects in cancer progression through the breakdown of extracellular LPA and S1P and other intracellular substrates. This review is intended to summarize an up-to-date understanding about the functions of LPPs in cancers.
7
Kidder, D. L., and K. Swett. "Basal Cambrian reworked phosphates from Spitsbergen (Norway) and their implications." Geological Magazine 126, no. 1 (January 1989): 79–88. http://dx.doi.org/10.1017/s0016756800006166.
Full textAbstract:
AbstractSeveral phosphatic zones are associated with the oldest remains of shelly fossils on the arctic island of Spitsbergen. The phosphate occurs as reworked nodules and layers associated with a disconformity. A gap in the acritarch biostratigraphic record supports a hiatus associated with the phosphatic zone. Palaeogeographic positions for Svalbard, both (1) as a single unit, and (2) as three isolated parts prior to Caledonian tectonism are consistent with conditions favourable to at least minimal amounts of upwelling. However, upwelling may not have been a prerequisite for development of these phosphate deposits. These phosphates were deposited in a nearshore shelf environmnt which contrasts with the outer shelf setting of many modern and recent phosphate deposits.Geochemistry of the Lower Cambrian phosphates of Spitsbergen varies with the mode of phosphate occurrence. Concretionary phosphate clasts are chemically zoned such that their centres are enriched in P2O5 and CaO and are depleted in A12O3, SiO2, and K2O. Laminated and thinly bedded phosphate shows no chemical zonation within clasts. Phosphate cements are the most pure with respect to calcium phosphate.This thin phosphatic zone of Svalbard is minor when compared with thicker and richer Lower Cambrian phosphate deposits, particularly those in the Soviet Union, Southeast Asia, and Australia. Coupled with the near absence of phosphate in some extensive Proterozoic to Lower Palaeozoic successions (e.g. western North America), this emphasizes the fact that widespread Lower Cambrian phosphate deposition was unevenly distributed. Althouth the Upper Proterozoic and Lower Cambrian are characterized by enhanced phosphogenesis, palaeogeographic position was also apparently critical to deposition of phosphatic sediments.
8
Klumpp, Susanne, Jan Hermesmeier, Dagmar Selke, Ralf Baumeister, Roland Kellner, and Josef Krieglstein. "Protein Histidine Phosphatase: A Novel Enzyme with Potency for Neuronal Signaling." Journal of Cerebral Blood Flow & Metabolism 22, no. 12 (December 2002): 1420–24. http://dx.doi.org/10.1097/01.wcb.0000045041.03034.99.
Full textAbstract:
The importance of reversible phosphorylation for neuronal signaling and cell survival is well recognized. Knowledge in vertebrates, however, is so far limited to O-phosphates from serine, threonine, and tyrosine. The authors describe an enzyme acting on N-phosphates. It is the first protein histidine phosphatase identified in vertebrates. This histidine phosphatase is ubiquitously expressed in mammalian tissues including brain. Characterization and sequencing showed a yet unknown protein with no similarity to other phosphatases. In Caenorhabditis elegans, the homolog of this histidine phosphatase was exclusively expressed in neurons, suggesting a distinct role of reversible histidine phosphorylation in neuronal functions.
9
Höer, A., and E. Oberdisse. "Inositol 1,3,4,5,6-pentakisphosphate and inositol hexakisphosphate are inhibitors of the soluble inositol 1,3,4,5-tetrakisphosphate 3-phosphatase and the inositol 1,4,5-trisphosphate/1,3,4,5-tetrakisphosphate 5-phosphatase from pig brain." Biochemical Journal 278, no. 1 (August 15, 1991): 219–24. http://dx.doi.org/10.1042/bj2780219.
Full textAbstract:
The influence of highly phosphorylated inositol phosphates on the Ins(1,3,4,5)P4 3-phosphatase enriched from the soluble fraction of pig brain was tested, using [5-32P]Ins(1,3,4,5)P4 as substrate. Both Ins(1,3,4,5,6)P5 and InsP6 were very potent inhibitors of the Ins(1,3,4,5)P4 3-phosphatase. The Ki values were approximately 60 nM and approximately 3 nM for Ins(1,3,4,5,6)P5 and InsP6 respectively. Ins(1,3,4,5,6)P5 and InsP6 also inhibited the Ins(1,4,5)P3/Ins(1,3,4,5)P4 5-phosphatase. Using Ins(1,3,4,5)P4 as substrate, the Ki values were about 35 microM and 15 microM for Ins(1,3,4,5,6)P5 and InsP6 respectively. The concentrations which led to a 50% inhibition of Ins(1,4,5)P3 (0.5 microM) degradation by the 5-phosphatase were about 20 and 10 microM for the pentakis- and hexakis-phosphate respectively. As the intracellular concentrations of Ins(1,3,4,5,6)P5 and InsP6 are high (up to 60 microM) compared with those of the inositol trisphosphates and tetrakisphosphates, it is possible that the highly phosphorylated inositol phosphates act as regulators in the metabolism of Ca(2+)-mobilizing inositol phosphates.
10
SUÁREZ, V. B., L. FRISÓN, M. Z. de BASÍLICO, M. RIVERA, and J. A. REINHEIMER. "Inhibitory Activity of Phosphates on Molds Isolated from Foods and Food Processing Plants." Journal of Food Protection 68, no. 11 (November 1, 2005): 2475–79. http://dx.doi.org/10.4315/0362-028x-68.11.2475.
Full textAbstract:
Six commercial phosphates were evaluated for inhibition of the growth of 17 molds isolated from food sources. The assays were performed at neutral and natural (without pH adjustment) pH values, and the molds were streaked on plate count agar with added phosphates. Phosphate concentrations of 0.1, 0.3, 0.5, 1.0, and 1.5% (wt/vol) were used, and the MIC was determined. The resistance of molds to phosphates depended on the species. At a neutral pH, Aspergillus ochraceus and Fusarium proliferatum were resistant to all phosphates at all concentrations assayed, and Byssochlamys nivea, Aureobasidium pullulans, and Penicillium glabrum were most sensitive. The most inhibitory phosphates were those with chain lengths greater than 15 phosphate units and the highest sequestering power. At natural pH values (resulting from dissolving the phosphate in the medium), inhibitory activity changed dramatically for phosphates that produced alkaline or acidic pH in the medium. Phosphates with alkaline pH values (sodium tripolyphosphate of high solubility, sodium tripolyphosphate, and sodium neutral pyrophosphate) were much more inhibitory than phosphates at a neutral pH, but sodium acid pyrophosphate (acidic pH) had decreased inhibitory activity. The results indicate that some phosphates could be used in the food industry to inhibit molds linked to food spoilage.
11
Le Mare, P. H. "Rock Phosphates in Agriculture." Experimental Agriculture 27, no. 4 (October 1991): 413–22. http://dx.doi.org/10.1017/s0014479700019396.
Full textAbstract:
SUMMARYThe principles that control effectiveness of rock phosphates as fertilizer are now fairly well understood so that the potential effect of a material can be predicted with some confidence from laboratory analysis of the raw material. Soil characteristics, especially acidity, and calcium and phosphate status, are important: if these are not conducive to dissolution, crop response to rock phosphate is small. Some crop characteristics, especially the extent of root systems and whether they are infected with mycorrhizae, also affect utilization of rock phosphate. Dissolution of rock phosphates may be too slow for rapidly growing crops but may be adequate for perennial crops.Such factors limit the use of rock phosphates for direct application, so that much greater knowledge of the characteristics of the phosphates, soils and crops, and their interactions, is necessary for their successful use than for the soluble phosphates. Economic considerations are important also. Because the phosphate content is less than that of concentrated soluble fertilizers, the cost of transporting rock phosphates, per unit of phosphorus, may not be economic. However, for acid and calcium deficient soils the larger amounts of calcium that rock phosphates supply may be an advantage and may lessen or eliminate the need for lime, especially for crops that require relatively large amounts of calcium.Fosfatos de roca en la agricultura
12
Swetha, Seshagiri, and Tallapragada Padmavathi. "Study of Acid Phosphatase in Solubilization of Inorganic Phosphates by Piriformospora indica." Polish Journal of Microbiology 65, no. 4 (December 28, 2016): 407–12. http://dx.doi.org/10.5604/17331331.1227666.
Full textAbstract:
Phosphorus is an essential plant macronutrient present in the soil. Only a small portion of phosphorus in soil is taken up by plants and the rest of it becomes unavailable to plants as it is immobilized. Phosphate solubilizing microorganisms play a vital role in converting the insoluble form of phosphates to the soluble form. The present paper reports the solubilization of tricalcium phosphate, rock phosphate, single super phosphate, zinc phosphate and aluminum phosphate by Piriformospora indica with the production of organic acids as well as acid phosphatase. The amount of phosphate released (4.73 mg ml-1) and titratable acidity (0.12%) was found to be the highest in the case of single super phosphate as compared to other phosphate sources. High performance liquid chromatography (HPLC) revealed the presence of oxalic acid, lactic acid, citric acid and succinic acid in the media. Highest phosphatase activity was observed with the cell membrane extract of the organism in the presence of zinc phosphate.
13
Füleky, György. "Phosphorus Supply of Typical Hungarian Soils." Agrokémia és Talajtan 55, no. 1 (March 1, 2006): 117–26. http://dx.doi.org/10.1556/agrokem.55.2006.1.13.
Full textAbstract:
The new hot water percolation (HWP) method was introduced to determine the phosphorus supply of soils from the Soil Bank of 36 Hungarian soils. The present work aimed to explain the availability of phosphorus by determining the inorganic phosphate fractions and using ryegrass test plants. Four inorganic phosphate fractions were distinguished: Fraction I, the sorbed phosphates; Fraction II, the easily soluble Ca phosphates and the Al bound phosphates; Fraction III, the Fe phosphates; and Fraction IV, the hardly soluble Ca phosphates. Fraction II, in which the easily soluble Ca phosphates and Al phosphates accumulate, was the main phosphorus source for the test plants on both calcareous and non-calcareous soils. Fraction III (the iron phosphates) plays a greater role in non-calcareous soils, while Fraction IV (the hardly soluble Ca phosphates) in calcareous soils. Both fractions are closely connected with soil development, and with soil properties such as pH and CaCO 3 content. The hot water percolation method reflects the phosphorus supply of soil as well as that measured with ryegrass plants and with the AL method. This new HWP method is in good correlation with the main source of phosphate, with fraction II. For routine purposes the first collected HWP fraction can possibly be used to determine the phosphorus supply of soil correlating well with the phosphorus uptake of test plants.
14
Timofeeva, Anna, Maria Galyamova, and Sergey Sedykh. "Prospects for Using Phosphate-Solubilizing Microorganisms as Natural Fertilizers in Agriculture." Plants 11, no. 16 (August 15, 2022): 2119. http://dx.doi.org/10.3390/plants11162119.
Full textAbstract:
Phosphates are known to be essential for plant growth and development, with phosphorus compounds being involved in various physiological and biochemical reactions. Phosphates are known as one of the most important factors limiting crop yields. The problem of phosphorus deficiency in the soil has traditionally been solved by applying phosphate fertilizers. However, chemical phosphate fertilizers are considered ineffective compared to the organic fertilizers manure and compost. Therefore, increasing the bioavailability of phosphates for plants is one of the primary goals of sustainable agriculture. Phosphate-solubilizing soil microorganisms can make soil-insoluble phosphate bioavailable for plants through solubilization and mineralization. These microorganisms are currently in the focus of interest due to their advantages, such as environmental friendliness, low cost, and high biological efficiency. In this regard, the solubilization of phosphates by soil microorganisms holds strong potential in research, and inoculation of soils or crops with phosphate-solubilizing bacteria is a promising strategy to improve plant phosphate uptake. In this review, we analyze all the species of phosphate-solubilizing bacteria described in the literature to date. We discuss key mechanisms of solubilization of mineral phosphates and mineralization of organic phosphate-containing compounds: organic acids secreted by bacteria for the mobilization of insoluble inorganic phosphates, and the enzymes hydrolyzing phosphorus-containing organic compounds. We demonstrate that phosphate-solubilizing microorganisms have enormous potency as biofertilizers since they increase phosphorus bioavailability for the plant, promote sustainable agriculture, improve soil fertility, and raise crop yields. The use of phosphate-solubilizing microbes is regarded as a new frontier in increasing plant productivity.
15
Helard, Denny, Shinta Indah, and Afdila Ardon. "Analysis of spatial variation of phosphates in Batang Arau River, Indonesia." MATEC Web of Conferences 276 (2019): 06028. http://dx.doi.org/10.1051/matecconf/201927606028.
Full textAbstract:
This study aims to study the spatial variation of phosphates (orthophosphate, total phosphate, and organic phosphate) in the Batang Arau River, West Sumatera, Indonesia. Sampling was conducted at eight stations along the river from March to May 2014. The results indicate that the three types of phosphates have similar spatial distribution patterns, with an increasing trend in concentration from upstream to downstream. The results also showed that the average orthophosphate and total phosphates concentrations at most of sampling sites had exceeded the quality standard for river water in West Sumatera (class II < 0.2 mg/L) except in the upstream. The mean concentrations of orthophosphate, total phosphates and organic phosphate were 0.054-0.423 mg/L, 0.067-0.446 mg/L, and 0.013-0.072 mg/L, respectively. Analysis of spatial variation with ANOVA at 95% confidence level indicated that differences in land use and human activities along the Batang Arau River resulted in significant differences in phosphates concentration (p < 0.05), except for organic phosphate.
16
Huck, Jojanneke H. J., Eduard A. Struys, Nanda M. Verhoeven, Cornelis Jakobs, and Marjo S. van der Knaap. "Profiling of Pentose Phosphate Pathway Intermediates in Blood Spots by Tandem Mass Spectrometry: Application to Transaldolase Deficiency." Clinical Chemistry 49, no. 8 (August 1, 2003): 1375–80. http://dx.doi.org/10.1373/49.8.1375.
Full textAbstract:
Abstract Background: Recently, several patients with abnormal polyol profiles in body fluids have been reported, but the origins of these polyols are unknown. We hypothesized that they are derived from sugar phosphate intermediates of the pentose phosphate pathway (PPP), and we developed a semiquantitative method for profiling of pentose phosphate pathway intermediates. Methods: Sugar phosphates in blood spots were simultaneously analyzed by liquid chromatography–tandem mass spectrometry using an ion-pair-loaded C18 HPLC column. The tandem mass spectrometer was operated in the multiple-reaction monitoring mode. Enzymatically prepared d-[13C6]glucose 6-phosphate was used as internal standard. The method was used to study sugar phosphates abnormalities in a patient affected with a deficiency of transaldolase (TALDO1; EC 2.2.1.2). Results: In control blood spots, dihydroxyacetone phosphate, pentulose 5-phosphates, pentose 5-phosphates, hexose 6-phosphates, and sedoheptulose 7-phosphate were detected. Detection limits ranged from ∼100 to ∼500 nmol/L. Glyceraldehyde 3-phosphate and erythrose 4-phosphate were undetectable. Intra- and interassay imprecision (CVs) were 10–17% and 12–21%, respectively. In blood from the TALDO1-deficient patient, sedoheptulose 7-phosphate was increased. Conclusions: The new method allows investigation of patients in whom a defect in the PPP is suspected. Measurements of sugar phosphate intermediates of the PPP may provide new insights into metabolic defects underlying the accumulating polyols.
17
Kluger, Ronald, Xianfeng Li, and Richard W. Loo. "1996 Bader Award Lecture Aminoacyl ethyl phosphates. Biomimetically activated amino acids." Canadian Journal of Chemistry 74, no. 12 (December 1, 1996): 2395–400. http://dx.doi.org/10.1139/v96-268.
Full textAbstract:
Aminoacyl ethyl phosphates are functional analogues of aminoacyl adenylates, the activated intermediates formed by ribosomal enzymes from the reaction of amino acids with ATP. The aminoacyl ethyl phosphates are prepared by DCC-mediated coupling of a tetraalkylammonium salt of ethyl phosphate and an N-t-Boc-amino acid, followed by deprotection. The efficiency of the synthesis and the solubility properties of the product depend on the alkyl group in the ammonium counterion of the phosphate. N-Protected and free aminoacyl ethyl phosphates hydrolyze slowly ([Formula: see text] in neutral solution, 25 °C, ~100 h). These materials are potentially useful in biomimetic peptide synthesis, protein modification, and aminoacylation of RNA. Key words: amino acids, acyl phosphates, aminoacyl phosphates, biomimetic aminoacylation.
18
L. M., Tokmakova, and Trepach A. O. "PHOSPHORUS BIOTRANSFORMATION IN ROOT ZONE OF CORN PLANTS UNDER ACTION OF AHROBACTERYN AND MINERAL FERTILIZERS." Agriciltural microbiology 34 (November 11, 2021): 44–52. http://dx.doi.org/10.35868/1997-3004.34.44-52.
Full textAbstract:
Objective. To determine the intensity of phosphorus biotransformation in the root zone of corn plants under the action of the microbial preparation Ahrobacteryn and various rates of mineral fertilizers. Methods. Field experiment (on leached chernozem), microbiological (accounting for the number of phosphate-mobilizing bacteria in the rhizosphere of corn plants, biochemical (determination of phosphatase activity, the degree of mobility of phosphates in the rhizosphere soil of plants), statistical. Results. It was found that during the growing season, the number of bacteria that hydrolyze mineral phosphorus compounds and organic soil phosphates increases in the rhizosphere soil of corn plants under the influence of the microbial preparation Ahrobacteryn. Given the features of the influence of mineral fertilizers on the development of phosphate-mobilizing bacteria in the rhizosphere soil of corn plants, it is optimal to use fertilizers in doses not exceeding N90P90K90. At the same time, phosphatase activity of the rhizosphere soil reaches the highest values in the flowering phase; in the phase of milk-wax ripeness of corn grain, the parameters are significantly reduced due to the slowdown in the absorption of phosphorus by plants. The effect of inoculation increases the degree of phosphate mobility in the rhizosphere soil of plants, which is expressed in a decrease in their content due to increased uptake by plants. In the phase of milk-wax ripeness, the mobility of phosphates decreases from 0.42 (in the control without fertilizers) to 0.23 mg P2O5/dm3 of soil solution, which indicates increased absorption of phosphorus by plants. Conclusion. Under the influence of Ahrobacteryn, the processes of phosphorus transformation in the root zone of corn plants are activated, the number of phosphate-mobilizing bacteria increases, phosphatase activity improves and the degree of phosphate mobility, which has an effect on the absorption of phosphorus by plants. As a result, phosphorus removal increases with a crop yield from 51.2 (in the control without fertilizers) to 83.4 kg/ha (with Ahrobacteryn), the efficiency of phosphorus plant nutrition after introduction of N90P90K90 is 62.9 %.
19
Bäck, Magnus, and Jean-Baptiste Michel. "From organic and inorganic phosphates to valvular and vascular calcifications." Cardiovascular Research 117, no. 9 (February 9, 2021): 2016–29. http://dx.doi.org/10.1093/cvr/cvab038.
Full textAbstract:
Abstract Calcification of the arterial wall and valves is an important part of the pathophysiological process of peripheral and coronary atherosclerosis, aortic stenosis, ageing, diabetes, and chronic kidney disease. This review aims to better understand how extracellular phosphates and their ability to be retained as calcium phosphates on the extracellular matrix initiate the mineralization process of arteries and valves. In this context, the physiological process of bone mineralization remains a human model for pathological soft tissue mineralization. Soluble (ionized) calcium precipitation occurs on extracellular phosphates; either with inorganic or on exposed organic phosphates. Organic phosphates are classified as either structural (phospholipids, nucleic acids) or energetic (corresponding to phosphoryl transfer activities). Extracellular phosphates promote a phenotypic shift in vascular smooth muscle and valvular interstitial cells towards an osteoblast gene expression pattern, which provokes the active phase of mineralization. A line of defense systems protects arterial and valvular tissue calcifications. Given the major roles of phosphate in soft tissue calcification, phosphate mimetics, and/or prevention of phosphate dissipation represent novel potential therapeutic approaches for arterial and valvular calcification.
20
Dubinina, Marina N., and Olga S. Bezuglova. "The Impact of a Humic Preparation on the Fractional Composition of Phosphates in Calcic Chernozem." UNIVERSITY NEWS. NORTH-CAUCASIAN REGION. NATURAL SCIENCES SERIES, no. 1 (213) (March 31, 2022): 38–48. http://dx.doi.org/10.18522/1026-2237-2022-1-38-48.
Full textAbstract:
The results of changes in the fractional composition of phosphorus in Calcic Chernozem under the influence of foliar treatment of winter wheat crops with a humic preparation are presented. Research was carried out in 2017–2020 at the experimental field of Federal Rostov Agricultural Research Center. The treatment of crops was carried out in the phases of tillering and heading. Studies have shown that the treatment of winter wheat crops with a humic preparation helps to reduce all forms of mineral phosphates in the soil, especially phosphates of the first group, the most accessible to plants. However, other groups, including hard-to-reach aluminum and iron phosphates, are also involved in this process. The reason is the increased need for phosphorus nutrition in the plants that received stimulating treatments with a humic preparation. Winter wheat plants regulate the release of bound forms of phosphate by including phosphatase in the process.
21
Pinto, Paola H., Alena Kroupova, Alexander Schleiffer, Karl Mechtler, Martin Jinek, Stefan Weitzer, and Javier Martinez. "ANGEL2 is a member of the CCR4 family of deadenylases with 2′,3′-cyclic phosphatase activity." Science 369, no. 6503 (July 30, 2020): 524–30. http://dx.doi.org/10.1126/science.aba9763.
Full textAbstract:
RNA molecules are frequently modified with a terminal 2′,3′-cyclic phosphate group as a result of endonuclease cleavage, exonuclease trimming, or de novo synthesis. During pre-transfer RNA (tRNA) and unconventional messenger RNA (mRNA) splicing, 2′,3′-cyclic phosphates are substrates of the tRNA ligase complex, and their removal is critical for recycling of tRNAs upon ribosome stalling. We identified the predicted deadenylase angel homolog 2 (ANGEL2) as a human phosphatase that converts 2′,3′-cyclic phosphates into 2′,3′-OH nucleotides. We analyzed ANGEL2’s substrate preference, structure, and reaction mechanism. Perturbing ANGEL2 expression affected the efficiency of pre-tRNA processing, X-box–binding protein 1 (XBP1) mRNA splicing during the unfolded protein response, and tRNA nucleotidyltransferase 1 (TRNT1)–mediated CCA addition onto tRNAs. Our results indicate that ANGEL2 is involved in RNA pathways that rely on the ligation or hydrolysis of 2′,3′-cyclic phosphates.
22
Hanke, David E., Paroo N. Parmar, Samuel E. K. Caddick, Porntip Green, and Charles A. Brearley. "Synthesis of inositol phosphate ligands of plant hormone–receptor complexes: pathways of inositol hexakisphosphate turnover." Biochemical Journal 444, no. 3 (May 29, 2012): 601–9. http://dx.doi.org/10.1042/bj20111811.
Full textAbstract:
Reduction of phytate is a major goal of plant breeding programs to improve the nutritional quality of crops. Remarkably, except for the storage organs of crops such as barley, maize and soybean, we know little of the stereoisomeric composition of inositol phosphates in plant tissues. To investigate the metabolic origins of higher inositol phosphates in photosynthetic tissues, we have radiolabelled leaf tissue of Solanum tuberosum with myo-[2-3H]inositol, undertaken a detailed analysis of inositol phosphate stereoisomerism and permeabilized mesophyll protoplasts in media containing inositol phosphates. We describe the inositol phosphate composition of leaf tissue and identify pathways of inositol phosphate metabolism that we reveal to be common to other kingdoms. Our results identify the metabolic origins of a number of higher inositol phosphates including ones that are precursors of cofactors, or cofactors of plant hormone–receptor complexes. The present study affords alternative explanations of the effects of disruption of inositol phosphate metabolism reported in other species, and identifies different inositol phosphates from that described in photosynthetic tissue of the monocot Spirodela polyrhiza. We define the pathways of inositol hexakisphosphate turnover and shed light on the occurrence of a number of inositol phosphates identified in animals, for which metabolic origins have not been defined.
23
Li, Guang Lei, Fei Lu, Su Juan Du, and Jie Zeng. "Optimization of Preparation of Sweet Potato Starch Phosphates of High Paste Stability by Response Surface Methodology." Advanced Materials Research 236-238 (May 2011): 2340–43. http://dx.doi.org/10.4028/www.scientific.net/amr.236-238.2340.
Full textAbstract:
The preparation of sweet potato starch phosphates which possess height stable paste was optimized in this study. A central composite design of response surface methodology involving phosphate (sodium dihydrogen phosphate and disodium hydrogen phosphate) concentration, the ratio of sodium dihydrogen phosphate and disodium hydrogen phosphate, phosphorylation temperature and urea concentration was used, and second-order model for paste stability was employed to generate the response surface. The optimum condition for preparation of sweet potato starch phosphates was as follows: phosphate concentration 4.89%, the ratio of sodium dihydrogen phosphate and disodium hydrogen 0.50, phosphorylation temperature 143°C, urea concentration 2.0%. The predicted value for paste stability of sweet potato starch phosphates at the optimum condition was 0.5721. Experimental verification gave values of 0.5708±0.0003.
24
Van Schaftigen, E. "Glucosamine-sensitive and -insensitive detritiation of [2-3H]glucose in isolated rat hepatocytes: a study of the contributions of glucokinase and glucose-6-phosphatase." Biochemical Journal 308, no. 1 (May 15, 1995): 23–29. http://dx.doi.org/10.1042/bj3080023.
Full textAbstract:
Glucosamine, a potent inhibitor of glucokinase (hexokinase IV or D), was used to estimate the contribution of this enzyme to glucose phosphorylation in freshly isolated rat hepatocytes and its sensitivity to fructose 6-phosphate in situ. Experiments with radiolabelled glucosamine indicated that this amino sugar, at concentrations of 5 or 40 mM, readily penetrated hepatocytes to reach in 1 min a total (i.e., glucosamine+metabolites) intracellular concentration equal to 0.8-1.2-fold its extracellular concentration. In marked contrast, N-acetylglucosamine barely penetrated the cells. The detritiation of [2-3H]glucose, used to estimate glucose phosphorylation in intact cells, was inhibited by glucosamine much more potently than by N-acetylglucosamine, half-maximal effects being reached at about 2.5 and 30 mM respectively. Extrapolation of the data indicated that about 12% of the detritiation was resistant to glucosamine. Dihydroxyacetone (10 mM), lactate (10 mM) + pyruvate (1 mM), and glucagon (1 microM) increased up to 8-fold the concentration of hexose 6-phosphates (glucose 6-phosphate+fructose 6-phosphate) and, against expectations, modestly decreased the detritiation rate measured in the absence of glucosamine. In the presence of 40 mM glucosamine, these agents increased the detritiation rate, which then positively correlated with the concentration of hexose 6-phosphates. This hexose 6-phosphates-dependent detritiation was sensitive to inhibition by vanadate, and was also catalysed by gel-filtered cell-free extracts, as well as by liver microsomes in the presence of phosphoglucoisomerase; it can be explained by an exchange reaction catalysed by glucose-6-phosphatase. When this exchange reaction is taken into account, it appears that the rate of glucose detritiation attributable to glucokinase decreases when the concentration of hexose 6-phosphates increases. This is in agreement with the known effect of fructose 6-phosphate to potentiate the inhibition of glucokinase by its regulatory protein.
25
Rubiera, C., P. S. Lazo, and S. B. Shears. "Polarized subcellular distribution of the 1-, 4- and 5-phosphatase activities that metabolize inositol 1,4,5-trisphosphate in intestinal epithelial cells." Biochemical Journal 269, no. 2 (July 15, 1990): 353–58. http://dx.doi.org/10.1042/bj2690353.
Full textAbstract:
In intestinal epithelial cells, Ins(1,4,5)P3 is metabolized both by an intracellular 5-phosphatase and by less specific extracellular phosphatases [Rubiera, Velasco, Michell, Lazo & Shears (1988) Biochem. J. 255, 131-137]. A total of 91% of intracellular Ins(1,4,5)P3 5-phosphatase was particulate, and was preferentially associated with plasma membranes rather than with other subcellular organelles. A soluble Ins(1,4,5)P3 3-kinase activity was also characterized, further supporting the idea that inositol phosphates are important in enterocyte function. We have studied the distribution of Ins(1,4,5)P3 phosphatase activities in basolateral and brush-border domains of the plasma membrane. Compared with homogenates, the extracellular phosphatases were 13-17-fold enriched in brush-border membranes, but only 2-fold enriched in basolateral membranes. The 1- and 4-phosphates of Ins(1,4,5)P3 were hydrolysed at equal rates by the extracellular phosphatases; these enzymes are proposed to have digestive functions. The intracellular particulate 5-phosphatase was 2-fold enriched in brush-border membranes and 13-fold enriched in basolateral membranes, at the same pole of the cell where Ins(1,4,5)P3 is believed to be generated. This is opposite to the polarized distribution of particulate 5-phosphatase in hepatocytes [Shears, Evans, Kirk & Michell (1988) Biochem. J. 256, 363-369]; these differences in subcellular distribution may be important in determining cell-specific metabolism of Ins(1,4,5)P3.
26
Sibi, G. "Role of phosphate solubilizing fungi during phosphocompost production and their effect on the growth of tomato (Lycopersicon esculentum L) plants." Journal of Applied and Natural Science 3, no. 2 (December 1, 2011): 287–90. http://dx.doi.org/10.31018/jans.v3i2.199.
Full textAbstract:
Experiments were conducted to evaluate the effect of phosphate solubilizing fungi (Aspergillus awamori and Trichoderma viride) in phosphocompost preparation along with low grade rock phosphate. Co-inoculation of phosphate-solubilizing fungi significantly increased the nutrient value of the compost that explores high P-solubilizing potential of A.awamori and T.viride which can be exploited for the solubilization of fixed phosphates thereby enhancing soil fertility and plant growth. Rock phosphate application along with phosphate solubilizing fungi increased 69.2% acid phosphatase and 65% alkaline phosphatase activity over ordinary compost. With co-inoculation, maximum P content (64.3%) was observed followed by single inoculation with A.awamori (62.2%). The present findings revealed that phosphate solubilizing fungi can interact positively in promoting nutrient content of compost and plant growth leading to improved yield.
27
Ali, Ashraf Fahim, and Piercarlo Mustarelli. "Improving the synthesis of alkyl phosphates as sol-gel precursors." Journal of Materials Research 14, no. 2 (February 1999): 327–29. http://dx.doi.org/10.1557/jmr.1999.0047.
Full textAbstract:
Alkyl phosphates can be used as sol-gel precursors for phosphate-based glasses and glass-ceramics. An improvement in the synthesis of alkyl phosphates is presented. Following the procedure here described, it is possible to limit the fraction of condensed phosphates to 1–2%. At the same time, a ratio between mono- and di-substituted phosphates near to that given by the reaction stoichiometry may be attained.
28
ROCHA JUNIOR, Carlos Magno da, Alexandre de Oliveira TEIXEIRA, Melissa Izabel HANNAS, Ana Lúcia Almeida SANTANA, Thony Assis CARVALHO, Bárbara Lopes de OLIVEIRA, Leonardo Marmo MOREIRA, and Carla Regina Guimarães BRIGHENTI. "Digestibility of phosphorus in powder and microgranular phosphate in diets for pigs." Revista Brasileira de Saúde e Produção Animal 16, no. 3 (September 2015): 544–57. http://dx.doi.org/10.1590/s1519-99402015000300007.
Full textAbstract:
AbstractThis study was realized with the objective to determine the apparent and standardized digestibilities of phosphates to pigs in growing phase, employing two methodologies. Forty-two crossbred barrows with an initial weight of 37 ± 1.1kg were used in a randomized-block design in a 2 × 7 factorial arrangement, with two collection methods: total fecal collection and the use of a indicator (acid insoluble ash [AIA]) × seven treatments, which consisted of a control diet (CTR); three diets containing phosphate in powder form (PP): PPA= CTR + powder phosphate A, PPB= CTR + powder phosphate B, and PPC= CTR + powder phosphate C; and another three diets containing the microgranular phosphate (MP): MP15= CTR + microgranular phosphate 15%, MP45 = CTR + microgranular phosphate 45% and MP75= CTR + microgranular phosphate 75%). The values of 15, 45, and 75% correspond to the water-solubility of the phosphates. There were six replicates, and the pig was considered as experimental unit. The standardized digestibility coefficients of the phosphates assessed by the total collection method, in percent values, were: PPA = 86.9, PPB = 84.9, PPC = 81.9, MP15 = 89.4, MP45 = 88.8, and MP75 = 92.6. The standardized-digestibility coefficients of the phosphates evaluated by the indicator method (AIA) in percent values were: PPA = 75.9, PPB = 75.4, PPC = 75.6, MP15 = 84.9, MP45 = 78.0, and MP75 = 79.4. Considering the two methodologies evaluated in the present work, the microgranular phosphates constitute the best alternative for feeding pigs in the growth phase.
29
Dwibedi, Debasmita, Ritambhara Gond, Krishnakanth Sada, Baskar Senthilkumar, and Prabeer Barpanda. "Electrocatalytic Activity of Some Cobalt Based Sodium Phosphates in Alkaline Solution." MRS Advances 3, no. 22 (2018): 1215–20. http://dx.doi.org/10.1557/adv.2018.136.
Full textAbstract:
ABSTRACTThe development of efficient water oxidation catalyst is a major path to realize water splitting systems, which could benefit high performance and cost-effective metal-air batteries, fuel cells and solar energy conversion. To date, the rare crustal abundant platinum group metals rule this sector with Pt-alloys being the best for oxygen reduction reaction (ORR) and ruthenium oxides for oxygen evolution reaction (OER) in acidic solution. However, they show poor stability and are too expensive for large scale applications. Moreover, oxygen reduction in basic solutions can otherwise be catalysed by metal oxide with non-precious earth abundant transition metals (e.g. Fe, Co, Ni). Hence, there is a massive demand to explore noble metal free bifunctional electrocatalysts. In this work, we present the electrocatalytic activity of three cobalt based sodium phosphates namely NaCoPO4 (with one phosphate), Na2CoP2O7 (with two phosphate) NaFe2Co(PO4)3 (with three phosphate). Synthesized by solution combustion route, all these phosphates confirmed phase purity. NaCoPO4 and Na2CoP2O7 adopted orthorhombic structure with Pnma and Pna21 space group respectively; whereas NaFe2Co(PO4)3 crystallized in monoclinic (C2/c) framework. Electrocatalytic activity of these cobalt phosphates were inspected by linear sweep voltammetry with rotating disk electrode (RDE). All three showed promising bifunctional activity. In fact, the ORR activities of both orthorhombic cobalt phosphates are comparable to Vulcan carbon and Pt/C. OER activity of Na2CoP2O7 overrode other phosphates. The bifunctional activity and good stability of these sodium cobalt phosphates stem from cobalt ions and stabilization of the catalytic centres by the phosphate frameworks. The present work builds a detail structure-property correlation in these phosphate systems and also demonstrates the possibility of utilizing these sodium cobalt phosphates as alternate cost-effective, novel electrocatalysts for efficient OER/ORR activity in alkaline solution.
30
Livermore, Thomas M., Cristina Azevedo, Bernadett Kolozsvari, Miranda S. C. Wilson, and Adolfo Saiardi. "Phosphate, inositol and polyphosphates." Biochemical Society Transactions 44, no. 1 (February 9, 2016): 253–59. http://dx.doi.org/10.1042/bst20150215.
Full textAbstract:
Eukaryotic cells have ubiquitously utilized the myo-inositol backbone to generate a diverse array of signalling molecules. This is achieved by arranging phosphate groups around the six-carbon inositol ring. There is virtually no biological process that does not take advantage of the uniquely variable architecture of phosphorylated inositol. In inositol biology, phosphates are able to form three distinct covalent bonds: phosphoester, phosphodiester and phosphoanhydride bonds, with each providing different properties. The phosphoester bond links phosphate groups to the inositol ring, the variable arrangement of which forms the basis of the signalling capacity of the inositol phosphates. Phosphate groups can also form the structural bridge between myo-inositol and diacylglycerol through the phosphodiester bond. The resulting lipid-bound inositol phosphates, or phosphoinositides, further expand the signalling potential of this family of molecules. Finally, inositol is also notable for its ability to host more phosphates than it has carbons. These unusual organic molecules are commonly referred to as the inositol pyrophosphates (PP-IPs), due to the presence of high-energy phosphoanhydride bonds (pyro- or diphospho-). PP-IPs themselves constitute a varied family of molecules with one or more pyrophosphate moiety/ies located around the inositol. Considering the relationship between phosphate and inositol, it is no surprise that members of the inositol phosphate family also regulate cellular phosphate homoeostasis. Notably, the PP-IPs play a fundamental role in controlling the metabolism of the ancient polymeric form of phosphate, inorganic polyphosphate (polyP). Here we explore the intimate links between phosphate, inositol phosphates and polyP, speculating on the evolution of these relationships.
31
Ren, Yuechang, Yaping Liu, Kexin Jiang, Linkui Li, Ning Jiao, Zhengqi Zhu, Kaiying Zhang, Shuzhen Jiang, Weiren Yang, and Yang Li. "Effects of Low-Phosphorus Diets Supplemented with Phytase on the Production Performance, Phosphorus-Calcium Metabolism, and Bone Metabolism of Aged Hy-Line Brown Laying Hens." Animals 13, no. 6 (March 13, 2023): 1042. http://dx.doi.org/10.3390/ani13061042.
Full textAbstract:
This study was conducted to evaluate the effects of phytase supplementation in low-phosphorus diets on the production performance, phosphorus–calcium metabolism, and bone metabolism in laying hens from 69 to 78 weeks of age. Hy-Line Brown laying hens (n = 1350) were assigned randomly to six treatments with five replicates of 45 birds. A corn–soybean meal-based diet with no inorganic phosphates was formulated to contain 0.12% non-phytate phosphorus (NPP) and 1470 FTU/kg phytase (Released phytate phosphorus content ≥ 0.1%). Inorganic phosphorus (dicalcium phosphate) was supplemented into the basal diet to construct five test diets (level of NPP supplementation = 0.10%, 0.15%, 0.20%, 0.25%, and 0.30%). The level of calcium carbonate was adjusted to ensure that all six experimental diets contained the same calcium percentage (3.81%). The feeding trial lasted 10 weeks (hens from 69 to 78 weeks of age). Upon supplementation with phytase (1470 FTU/kg), supplemental inorganic phosphates (dicalcium phosphate) had no significant effects (p > 0.05) on the production performance or egg quality. Significant differences in serum levels of calcium, phosphorus, copper, iron, zinc, or manganese were not detected across treatments (p > 0.05). Hens fed NPP (0.15%, 0.20%, 0.25%, and 0.30%) had higher levels (p < 0.0001) of tibial ash, calcium, and phosphorus than those not fed inorganic phosphates. The tibial breaking strength of the group without inorganic phosphates was significantly lower than that of the other groups (p < 0.01). Dietary supplementation with inorganic phosphates had no effect (p > 0.05) on serum levels of calcitonin (CT) and 1,25-dihydroxy-vitamin D3 (1,25-(OH)2D3). Hens that did not receive supplementation with inorganic phosphates had higher serum levels of parathyroid hormone (PTH), osteoprotegerin (OPG), type-I collagen c-telopeptide (CTX-I), and tartrate-resistant acid phosphatase 5b (TRACP-5b) compared with those in the other groups (p < 0.01). Serum levels of CTX-I and TRACP-5b were significantly lower in the NPP-supplementation groups of 0.25% and 0.30% than in the 0.10% NPP-supplementation group (p < 0.01). Dietary supplementation with inorganic phosphates had no effect (p > 0.05) on serum levels of bone-alkaline phosphatase (BAP), osteocalcin (OCN), or osteopontin (OPN). Hens not fed inorganic phosphate had the highest renal expression of phosphorus transporter type IIa Na/Pi cotransporter (NaPi-Ⅱa). Renal expression of NaPi-Ⅱa was increased significantly in NPP-supplementation groups of 0.10–0.20% compared with that in NPP-supplementation groups of 0.25% and 0.30% (p < 0.0001). The results indicated that a reduction in NPP supplementation to 0.15% (dietary NPP level = 0.27%) with phytase inclusion did not have an adverse effect on the production performance or bone health of laying hens from 69 to 78 weeks of age, which might be attributed to renal phosphorus reabsorption and bone resorption. These findings could support the application of low-phosphorus diets in the poultry industry.
32
El Bamiki, Radouan, Otmane Raji, Muhammad Ouabid, Abdellatif Elghali, Oussama Khadiri Yazami, and Jean-Louis Bodinier. "Phosphate Rocks: A Review of Sedimentary and Igneous Occurrences in Morocco." Minerals 11, no. 10 (October 16, 2021): 1137. http://dx.doi.org/10.3390/min11101137.
Full textAbstract:
Phosphate rocks are a vital resource for world food supply and security. They are the primary raw material for phosphoric acid and fertilizers used in agriculture, and are increasingly considered to be a potential source of rare earth elements. Phosphate rocks occur either as sedimentary deposits or igneous ores associated with alkaline rocks. In both cases, the genesis of high-grade phosphate rocks results from complex concentration mechanisms involving several (bio)geochemical processes. Some of these ore-forming processes remain poorly understood and subject to scientific debate. Morocco holds the world’s largest deposits of sedimentary phosphate rocks, and also possesses several alkaline complexes with the potential to bear igneous phosphate ores that are still largely underexplored. This paper summarizes the main geological features and driving processes of sedimentary and igneous phosphates, and discusses their global reserve/resource situation. It also provides a comprehensive review of the published data and information on Moroccan sedimentary and igneous phosphates. It reveals significant knowledge gaps and a lack of data, inter alia, regarding the geochemistry of phosphates and basin-scale correlations. Owing to the unique situation of Moroccan phosphates on the global market, they clearly deserve more thorough studies that may, in turn, help to constrain future resources and/or reserves, and answer outstanding questions on the genesis of phosphates.
33
Hemming, Frank W. "Dolichol: a curriculum cognitionis." Biochemistry and Cell Biology 70, no. 6 (June 1, 1992): 377–81. http://dx.doi.org/10.1139/o92-058.
Full textAbstract:
Dolichols were first described about 30 years ago when animal tissues were being examined for the presence of a putative precursor to the polyisoprenoid side chain of ubiquinone. These long-chain 2,3-dihydro-polycis-isoprenoid alcohols are found in all eukaryotic organisms. In many plant tissues they are accompanied by families of other polyisoprenoid alcohols that are usually similar molecules and possess an unsaturated α-isoprene residue. Analogy with the role of bactoprenyl phosphates in the synthesis of bacterial wall glycans led to the discovery that the mono- and di-phosphates of dolichols function as cofactors in protein N-glycosylation, involving the formation of glycosylated derivatives of dolichol as intermediates. Variation of the concentration of dolichyl phosphate was shown to be one way of controlling protein N-glycosylation. This can be achieved by modification of the relative activities of dolichol kinase and dolichol phosphate phosphatase. Modulation of the biosynthetic pathway, still not fully understood, of dolichyl phosphate may also be an important factor. Several disease conditions involve aberrations in these pathways.Key words: dolichols, polyisoprenoid alcohols, N-glycosylation, O-mannosylation.
34
Joseph, S. K., T. Esch, and W. D. Bonner. "Hydrolysis of inositol phosphates by plant cell extracts." Biochemical Journal 264, no. 3 (December 15, 1989): 851–56. http://dx.doi.org/10.1042/bj2640851.
Full textAbstract:
A gel-filtered soluble fraction prepared from suspension-cultured Nicotiana tabacum cells hydrolysed inositol mono-, bis- and tris-phosphates. At a concentration of 7.5 microM the rates of hydrolysis followed the sequence Ins(1,4,5)P3 greater than Ins(1,4)P2 greater than Ins(4)P congruent to Ins(1)P. The major products of Ins(1,4,5)P3 hydrolysis identified by h.p.l.c. were Ins(1,4)P2 and Ins(4,5)P2. Ins(1,4)P2 was hydrolysed exclusively to Ins(4)P. The inclusion of Ca2+ in the incubation buffer markedly stimulated the hydrolysis of all the inositol phosphate substrates. Under identical conditions, Ca2+ inhibited the hydrolysis of inositol phosphates by soluble extracts prepared from rat brain. Half-maximal stimulation of Ins(1,4)P2 hydrolysis was obtained at free [Ca2+] of 0.6 and 1.2 microM when the Mg2+ concentration in the incubations was 0.3 and 1.0 mM respectively. This effect of Ca2+ was exerted solely by increasing the Vmax. of hydrolysis without affecting the Km for Ins(1,4)P2. Again, in contrast with brain, the hydrolysis of inositol bis- or mono-phosphates was insensitive to high concentrations of Li+. We conclude that plants contain specific Li+-insensitive inositol phosphate phosphatases that are regulated by low concentrations of Ca2+ in a manner which is different from that observed in mammalian tissues.
35
Schmidt, Susanne, and Friedrich Hammerschmidt. "Phosphate-Phosphonate Rearrangement of Aliphatic Phosphates." Phosphorus, Sulfur, and Silicon and the Related Elements 147, no. 1 (January 1, 1999): 377. http://dx.doi.org/10.1080/10426509908053668.
Full text
36
Ferreira, André Sampaio, Danilo Pinceli Chaves, Adilson De Oliveira Júnior, and Claudemir Zucareli. "Phosphate solubilizing rhizobacteria inoculation to increase rock phosphates efficiency and improve maize growth." DELOS: DESARROLLO LOCAL SOSTENIBLE 16, no. 44 (July 14, 2023): 1288–304. http://dx.doi.org/10.55905/rdelosv16.n44-018.
Full textAbstract:
Rock phosphates are less soluble and agronomically not as efficient as the acidulated. However, some rhizobacteria can improve the solubilization of inorganic phosphates in the soil, raising the efficiency of the rock phosphates. The objective was to evaluate the development of maize plants in response to the application of soluble and rock P sources associated with rhizobacteria inoculation. A greenhouse experiment was carried out with six P sources: no P application; Triple Superphosphate (TSPh); Gafsa rock phosphate (reactive); Itafós rock phosphate (non-reactive); TSPh + Gafsa; and TSPh + Itafós, and three inoculation forms: no inoculation, Burkholderia pickettii GN 2214 and Pseudomonas sp. fluorescens group P21. Plant height, stem diameter, leaf area, shoot dry weight (ShDW), root dry weight (RDW), total dry weight, cumulative P content in ShDW, RDW/ShDW ratio and relative agronomic efficiency were assessed. Agronomic efficiency and growth of the TSPh-treated plants were better than of those treated with rock phosphates. The association of TSPh with rock phosphates increases the agronomic efficiency and maize plant growth more than the isolated rock sources. Inoculation with P. fluorescens strain P21, improved the performance of maize fertilized with Gafsa phosphate, but had no effect when associated with Itafós phosphate. Together with TSPh, inoculation intensified shoot and root growth, indicating the potential to increase the efficiency of soluble sources as well.
37
Klöck, Gerd, and Karlheinz Kreuzberg. "Sn-Glycerol-3-phosphate is a Product of Starch Degradation in Isolated Chloroplasts from Chlamydomonas reinhardii." Zeitschrift für Naturforschung C 42, no. 5 (May 1, 1987): 567–69. http://dx.doi.org/10.1515/znc-1987-0512.
Full textAbstract:
Abstract Sn-glycerol-3-phosphate Sn-glycerol-3-phosphate accumulates during starch catabolism by intact isolated chloroplasts from Chlamydomonas reinhardii in the dark. Further products detected mainly were 3-phospho-glyceric acid and triose phosphates with a ratio between 3-phosphoglyceric acid, sn-glycerol-3-phosphate and triose phosphates of 1.0:0.9:0.2. The production of sn-glycerol-3-phosphate by a plastidic glycerol-3-phosphate dehydrogenase provides a reasonable mechanism for regenerating reducing equivalents during continuous starch breakdown in the chloroplast of the alga C. reinhardii.
38
Diaz-Moralli, Santiago, Antonio Ramos-Montoya, Silvia Marin, Ana Fernandez-Alvarez, Marta Casado, and Marta Cascante. "Target metabolomics revealed complementary roles of hexose- and pentose-phosphates in the regulation of carbohydrate-dependent gene expression." American Journal of Physiology-Endocrinology and Metabolism 303, no. 2 (July 15, 2012): E234—E242. http://dx.doi.org/10.1152/ajpendo.00675.2011.
Full textAbstract:
Carbohydrate response element-binding protein (ChREBP) is a transcription factor that mediates glucose signaling in mammalian liver, leading to the expression of different glycolytic and lipogenic genes, such as pyruvate kinase (L-PK) and fatty acid synthase (FAS). The current model for ChREBP activation in response to sugar phosphates holds that glucose metabolization to xylulose 5-phosphate (X-5- P) triggers the activation of protein phosphatase 2A, which dephosphorylates ChREBP and leads to its nuclear translocation and activation. However, evidence indicates that glucose 6-phosphate (G-6- P) is the most likely signal metabolite for the glucose-induced transcription of these genes. The glucose derivative that is responsible for carbohydrate-dependent gene expression remains to be identified. The difficulties in measuring G-6- P and X-5- P concentrations simultaneously and in changing them independently have hindered such identification. To discriminate between these possibilities, we adapted a liquid chromatography mass spectrometry method to identify and quantify sugar phosphates in human hepatocarcinoma cells (Hep G2) and rat hepatocytes in response to different carbon sources and in the presence/absence of a glucose-6-phosphate dehydrogenase inhibitor. We also used this method to demonstrate that these cells could not metabolize 2-deoxyglucose beyond 2-deoxyglucose-6-phosphate. The simultaneous quantification of sugar phosphates and FAS and L-PK expression levels demonstrated that both X-5- P and G-6- P play a role in the modulation of gene expression. In conclusion, this report presents for the first time a single mechanism that incorporates the effects of X-5- P and G-6- P on the enhancement of the expression of carbohydrate-responsive genes.
39
WAGNER, M. K. "Phosphates as Antibotulinal Agents in Cured Meats: A Review." Journal of Food Protection 49, no. 6 (June 1, 1986): 482–87. http://dx.doi.org/10.4315/0362-028x-49.6.482.
Full textAbstract:
Phosphates have been suggested as potential substitutes for the currently used nitrite in cured meat products, yet relatively little research has been done on the antibotulinal effects of phosphates. Phosphate selection for use in the cured meat industry continues to be based upon achieving certain functional objectives rather than microbiological control (i.e., improved tenderness, moisture retention, reduced shrinking during cooking, pH adjustments, emulsification, sequestration of ions). Current federal regulations limit addition of phosphates to amounts needed to achieve functionality. One notable exception is shelf-stable pasteurized processed cheese, cheese foods and cheese spreads, in which addition of phosphates for emulsification purposes also appears to provide antimicrobial or antibotulinal protection. It is, therefore, becoming evident that phosphates have the potential under certain conditions, of enhancing microbial or botulinal safety and stability of certain foods, with certain phosphates [i.e. sodium acid pyrophosphate (SAPP)] or mixture of phosphates displaying more effectiveness than others.
40
Afanou, Ablam Lazare, Magnoudewa Bassai Bodjona, Ida Diribissakou, Ayi Kevin Ajavon, Komlavi Hubert Edoh, and Gado Tchangbedji. "Caractérisation physico-chimique des composts élaborés à base des fientes de volaille et des déchets phosphatés du Togo." International Journal of Biological and Chemical Sciences 17, no. 7 (February 22, 2024): 2998–3007. http://dx.doi.org/10.4314/ijbcs.v17i7.30.
Full textAbstract:
Le traitement des phosphates naturels du Togo génère des déchets phosphatés (les refus de crible et la boue phosphatée) qui causent d’énormes problèmes environnementaux immédiats. L’objectif de ce travail était de valoriser ces déchets avec les fientes de volaille en compost. Quatre composts ont été élaborés : le compost A constitué de 66,7% de fientes de volaille et 33,3% de boue phosphatée ; le compost B constitué de 66,7% de fientes de volaille et 33,3% de refus de crible ; le compost C constitué de 66,7% de fientes de volailles, 16,7% de boue phosphatée et 16,7% de refus de crible puis le compost D constitué de 100% de fientes de volaille. Tous les composts ont présenté une température supérieure ou égale à 60°C pendant le processus de maturation. Le compost D seul a présenté un rapport C/N >10. Les teneurs en CaO dans les composts variaient de 55,30 à 73,16 mg/gMS et celles en P2O5 variaient de 34,40 à 140 mg/gMS. Les teneurs en Na2O et en K2O variaient respectivement de 15,13 à 24,01 mg/gMS et 12,60 à 36,80 mg/gMS. Tous les composts produits étaient riches en nutriments et pouvaient être utilisés pour restaurer les sols.
English title: Physico-chemical characterization of composts made from poultry droppings and phosphate wastes from Togo
Physico-chemical characterization of composts made from poultry droppings and phosphate wastes from Togo The processing of natural phosphates in Togo generates phosphate wastes (sieve residues and phosphate mud) which cause many immediate environmental problems. The objective of this research work was to recover these wastes with poultry droppings in compost. Four composts have been elaborated: compost A made up of 66.7% poultry droppings and 33.3% phosphate mud; compost B made up of 66.7% poultry droppings and 33.3% sieve residue; compost C made up of 66.7% poultry droppings, 16.7% phosphate mud and 16.7% sieve residue and compost D made up of 100% poultry droppings. All the composts presented a temperature greater than or equal to 60°C during the maturation process. Compost D alone had a C/N ratio of >10. The CaO contents in the composts varied from 55.30 to 73.16 mg/gMS and those of P2O5 varied from 34.40 to 140 mg/gMS. The Na2O and K2O contents varied respectively from 15.13 to 24.01 mg/gMS and 12.60 to 36.80mg/gMS. All the composts produced were rich in nutrients and could be used to refurbish soils.
41
Tian, Tian, Xin-Yi Chu, Yi Yang, Xuan Zhang, Ye-Mao Liu, Jun Gao, Bin-Guang Ma, and Hong-Yu Zhang. "Phosphates as Energy Sources to Expand Metabolic Networks." Life 9, no. 2 (May 22, 2019): 43. http://dx.doi.org/10.3390/life9020043.
Full textAbstract:
Phosphates are essential for modern metabolisms. A recent study reported a phosphate-free metabolic network and suggested that thioesters, rather than phosphates, could alleviate thermodynamic bottlenecks of network expansion. As a result, it was considered that a phosphorus-independent metabolism could exist before the phosphate-based genetic coding system. To explore the origin of phosphorus-dependent metabolism, the present study constructs a protometabolic network that contains phosphates prebiotically available using computational systems biology approaches. It is found that some primitive phosphorylated intermediates could greatly alleviate thermodynamic bottlenecks of network expansion. Moreover, the phosphorus-dependent metabolic network exhibits several ancient features. Taken together, it is concluded that phosphates played a role as important as that of thioesters during the origin and evolution of metabolism. Both phosphorus and sulfur are speculated to be critical to the origin of life.
42
Hausrath, E. M., C. T. Adcock, J. A. Berger, L. M. Cycil, T. V. Kizovski, F. M. McCubbin, M. E. Schmidt, et al. "Phosphates on Mars and Their Importance as Igneous, Aqueous, and Astrobiological Indicators." Minerals 14, no. 6 (June 4, 2024): 591. http://dx.doi.org/10.3390/min14060591.
Full textAbstract:
This paper reviews the phosphate phases in meteorites and those measured by landed spacecraft, what they reveal about past igneous and aqueous conditions on Mars, and important implications for potential prebiotic chemistry, past habitability, and potential biosignatures that could be detected in samples returned from Mars. A review of the 378 martian meteorites as of 2023 indicate that of the two most common phosphate minerals in Mars meteorites, merrillite and apatites, the apatite composition is largely F- and Cl-rich, with shergottites containing more OH. The phosphate concentrations examined across multiple missions show a relatively narrow range of phosphate, with higher concentrations observed in the Mount Sharp Group in Gale crater and Wishstone at Gusev crater and lower concentrations observed at Jezero crater floor and Jezero fan. Possible secondary phosphates detected on Mars, including Fe phosphates at Jezero crater and Gusev crater and Ca- and Al-bearing secondary phosphates, temperatures of formation of secondary phases and their dissolution rates and solubilities are reviewed and summarized. Despite this wealth of information about phosphates on Mars, due to their fine scale and relatively low concentrations, Mars Sample Return is needed to better understand phosphate and its implications for the igneous, aqueous, and astrobiological history of Mars.
43
Lopez, Diego A., and Hans H. Stein. "PSVI-8 Mineral composition of feed grade monocalcium phosphate." Journal of Animal Science 98, Supplement_3 (November 2, 2020): 200–201. http://dx.doi.org/10.1093/jas/skaa054.348.
Full textAbstract:
Abstract Feed phosphates are included in swine diets to meet the requirements of P. Two products are predominantly used for this purpose, commercial monocalcium phosphate (MCP) and dicalcium phosphate (DCP). Theoretically, pure MCP should contain 26.5% P but commercial sources of MCP contain around 21 % P. The reason there is less P in commercial sources is that these sources are contaminated with calcium carbonate and other minerals. In addition, feed grade phosphates called MCP in reality is a mixture of MCP and DCP, which also contributes to the reduced P. To determine the complete composition of commercial MCP, seven sources of MCP were procured. All sources were analyzed for most common minerals that may be present in feed phosphates (Table 1) Results indicate that the composition of minerals is relatively stable among the different sources of MCP, indicating that the process to produce feed grade phosphates does not result in much variability. However, none of the commercial feed grade phosphates contained close to 26.5% P, which would be expected in a pure source.
44
Dobenecker, Britta, Ellen Kienzle, and Stephanie Siedler. "The Source Matters–Effects of High Phosphate Intake from Eight Different Sources in Dogs." Animals 11, no. 12 (December 4, 2021): 3456. http://dx.doi.org/10.3390/ani11123456.
Full textAbstract:
Elevated serum phosphate concentrations are an established risk factor for cardiovascular disease and mortality in chronic kidney disease in various species. Independent associations of other parameters of phosphorus metabolism, such as phosphorus intake from different sources and serum concentrations of phosphorus, as well as parameters involved in the regulation, such as parathyroid hormone (PTH) or markers of bone turnover, have been studied in less detail. Therefore, the serum kinetics of phosphate, PTH, and the bone resorption marker bone-specific alkaline phosphatase (BAP) were investigated after 18 days of feeding a control diet and diets supplemented with eight different organic and inorganic phosphate sources aiming at 1.8% phosphorus per dry matter and calcium to phosphorus ratio between 1.3 and 1.7 to 1. Eight healthy beagle dogs (f/m, 2–4 years, 12.9 ± 1.4 kg body weight) were available for the trial. Highly significant differences in the serum kinetics of phosphorus, PTH, and BAP with the highest postprandial levels after feeding highly water-soluble sodium and potassium phosphates were found. We conclude that the use of certain inorganic phosphates in pet food is potentially harmful and should be restricted.
45
Tokmakova, L. M., А. О. Trepach, and І. M. Pyshchur. "MICROBIOLOGICAL TRANSFORMATION OF PHOSPHORUS IN THE ROOT ZONE OF SUNFLOWER UNDER THE ACTION OF BACILLUS SP. 2473 AND DIFFERENT DEGREES OF CROP FERTILIZATION." Agriciltural microbiology 38 (December 14, 2023): 40–50. http://dx.doi.org/10.35868/1997-3004.38.40-50.
Full textAbstract:
Objective. To study the peculiarities of the microbiological transformation of phosphorus compounds in the root zone of sunflower plants under the action of Bacillus sp. 2473 and different degrees of crop fertilization. Methods. Field experiment; microbiological (accounting for bacteria capable of dissolving insoluble phosphate complexes with Ca2+, Al3+, Fe3+ and hydrolysing organic phosphates in the rhizosphere soil of sunflower plants); biochemical (determination of soil phosphatase activity); chemical (determination of phosphorus content in soil and plants); statistical. Results. Under the conditions of the field experiment on leached chornozem, it was established that during the growing season of sunflower in the soil after the introduction of Bacillus sp. 2473 into the agrocenosis, the number of bacteria capable of dissolving insoluble complexes of phosphates with Ca2+, Al3+, Fe3+ and bacteria hydrolysing organic forms of phosphates increases compared to the indicators of the control variants. Phosphatase activity increases during the growing season of plants and reaches the highest values during the seed ripening phase. The lowest levels of phosphorus content in the rhizosphere soil of sunflower plants were registered after presowing inoculation with Bacillus sp. 2473. The content of Р2О5 decreased from 0.25 mg Р2О5/dm3 of the soil solution (in the control) to 0.21 mg Р2О5/dm3 in the phase of 7–8 leaves under the action of the inoculant; from 0.42 mg Р2О5/dm3 to 0.31 mg Р2О5/dm3 in the flowering phase; from 0.24 mg Р2О5/dm3 to 0.21 mg Р2О5/dm3 in the seed ripening phase, respectively, which indicates the strengthening of phosphorus assimilation by bacterized plants. The optimal agricultural background, taking into account the effect of fertilizers on the development of phosphate-mobilizing microorganisms, is the use of mineral fertilizers in a rate not exceeding N90P90K90. Conclusion. Under the influence of the phosphate-mobilizing bacterium Bacillus sp. 2473, the processes of phosphorus transformation are activated in the root zone of sunflower plants, which is indicated by an increase in the number of phosphate-mobilizing bacteria, phosphatase activity and the degree of phosphate mobility in the rhizosphere soil of plants. As a result, the assimilation of phosphorus by plants is enhanced, which is confirmed by the increase in its removal with crop yield from 47.3 kg/ha to 74.8 kg/ha, while the efficiency of phosphorus nutrition of plants is 53.8 % (against the background of N90P90K90).
46
Kluger, Ronald. "CIC Medal Award Lecture — Molecular keystones: Lessons from bioorganic reaction mechanisms." Canadian Journal of Chemistry 84, no. 9 (September 1, 2006): 1093–105. http://dx.doi.org/10.1139/v06-149.
Full textAbstract:
The work of the author is reviewed in terms of "keystone molecules" that serve as figurative points of support to understand the interactions of smaller molecules within biological macromolecules. The review emphasizes lessons learned in carboxylation of biotin, reactions of cyclic phosphates, the uses of acyl phosphate monoesters, and the mechanism of decarboxylation of thiamin-derived intermediates.Key words: CIC medal, biotin, ATP, mechanisms, cyclic phosphates, thiamin, acyl phosphates, catalysis.
47
Valsami-Jones, E. "Mineralogical controls on phosphorus recovery from wastewaters." Mineralogical Magazine 65, no. 5 (October 2001): 611–20. http://dx.doi.org/10.1180/002646101317018433.
Full textAbstract:
AbstractThe removal of phosphorus from wastewaters is becoming very common, to meet water quality targets, and avoid environmental problems related to eutrophication. At the same time, agricultural application of P-rich sewage biosolids is diminishing for reasons of logistics and of public pressure. As a result P from wastewaters is ultimately disposed of in landfills. Over the long term, phosphate ore reserves will become depleted. Recycling of P from wastewaters may thus be a realistic prospect if scientific and technical issues can be resolved. At the centre of the scientific problems lie considerations about optimizing phosphate precipitation as Ca phosphates. A number of Ca phosphate minerals exist, although by far the most common of these is hydroxylapatite. Precipitation kinetic considerations, however, suggest that other Ca phosphates (such as brushite, octacalcium phosphate, whitlockite, monetite or amorphous Ca phosphate) may initially precipitate, and later recrystallize into the most stable hydroxylapatite. This article reviews the complex precipitation mineralogy, chemistry and kinetics of Ca phosphates.
48
Franczak, Priscila Ferraz, Nelson Heriberto Almeida Camargo, Pricyla Corrêa, and Enori Gemelli. "Synthesis and Characterization of Hydrated Calcium Phosphate: Precursors for Obtaining Biocements." Materials Science Forum 798-799 (June 2014): 443–48. http://dx.doi.org/10.4028/www.scientific.net/msf.798-799.443.
Full textAbstract:
Calcium phosphates biocements are biomaterials that present crystallographic and mineralogical characteristics similar to human skeletal structure. This has led to the development of new calcium phosphates biomaterials for biomedical applications, especially biomaterials for repairing defects and bone reconstruction. Calcium phosphates biocements are a promising alternative in biomedical applications, for they are easy to mold, they have good wettability, hydration and hardening capacity during its application in biological means. This work aimed at the synthesis of hydrated calcium phosphates powder, through a simple reactive method, which will be the basis for the production of calcium phosphate biocimentos with self-setting reaction. Three calcium phosphates compositions were produced via CaCO3/phosphoric acid reactive method in the ratios Ca/P = 1,5; 1,6 e 1,67 molar. The presented results are associated to hydrated powder morphology and synthesis process control. Scanning Electron Microscopy (SEM) helped with the morphological characterization of the powders, the laser analysis method was used for determining particle size and the Fourier Transformed Infrared Spectroscopy (FTIR) gave support to the identification of H2O e PO43-grouping vibrational bands. The work showed that for the different powder compositions the hydrated calcium phosphate phase is formed by clustered fine particles. This demonstrated that the chosen synthesis method permits the obtention of hydrated calcium phosphates, precursors for later biocement production.
49
Lapeyrie, F., J. Ranger, and D. Vairelles. "Phosphate-solubilizing activity of ectomycorrhizal fungi in vitro." Canadian Journal of Botany 69, no. 2 (February 1, 1991): 342–46. http://dx.doi.org/10.1139/b91-046.
Full textAbstract:
An easy to use method is presented here to compare and study the mineral phosphate-solubilizing activity of ectomycorrhizal fungi. This technique can discriminate between strains with differing phosphate-solubilizing activities. Synthetic mineral phosphates, crystalline or amorphous, were differentially solubilized by 10 ectomycorrhizal fungi. Natural crystalline phosphates studied do not seem to be solubilized by fungi under similar experimental conditions. Paxillus involutus 1 appears to be able to solubilize calcium phosphates using either ammonium or nitrate nitrogen, but the other isolates were able to effectively solubilize phosphate only in the presence of ammonium. This has implications regarding the possible mechanism used to solubilize phosphate by these isolates. Recrystallization can be seen in the culture medium if calcium ions are present. The type of crystals depends on the phosphate source and on the fungal strain. This technique is suitable for screening a large number of ectomycorrhizal strains. The significance of phosphate-solubilizing activity to plant growth stimulation needs to be determined by field trials. Key words: ectomycorrhizal fungus, phosphate, solubilization.
50
Chamberlain, Philip P., Xun Qian, Amanda R. Stiles, Jaiesoon Cho, David H. Jones, Scott A. Lesley, Elizabeth A. Grabau, Stephen B. Shears, and Glen Spraggon. "Integration of Inositol Phosphate Signaling Pathways via Human ITPK1." Journal of Biological Chemistry 282, no. 38 (July 6, 2007): 28117–25. http://dx.doi.org/10.1074/jbc.m703121200.
Full textAbstract:
Inositol 1,3,4-trisphosphate 5/6-kinase (ITPK1) is a reversible, poly-specific inositol phosphate kinase that has been implicated as a modifier gene in cystic fibrosis. Upon activation of phospholipase C at the plasma membrane, inositol 1,4,5-trisphosphate enters the cytosol and is inter-converted by an array of kinases and phosphatases into other inositol phosphates with diverse and critical cellular activities. In mammals it has been established that inositol 1,3,4-trisphosphate, produced from inositol 1,4,5-trisphosphate, lies in a branch of the metabolic pathway that is separate from inositol 3,4,5,6-tetrakisphosphate, which inhibits plasma membrane chloride channels. We have determined the molecular mechanism for communication between these two pathways, showing that phosphate is transferred between inositol phosphates via ITPK1-bound nucleotide. Intersubstrate phosphate transfer explains how competing substrates are able to stimulate each others' catalysis by ITPK1. We further show that these features occur in the human protein, but not in plant or protozoan homologues. The high resolution structure of human ITPK1 identifies novel secondary structural features able to impart substrate selectivity and enhance nucleotide binding, thereby promoting intersubstrate phosphate transfer. Our work describes a novel mode of substrate regulation and provides insight into the enzyme evolution of a signaling mechanism from a metabolic role.