Academic literature on the topic 'Sporulation conditions'
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Journal articles on the topic "Sporulation conditions":
1
Ferreira, Julio C., Anita D. Panek, and Pedro S. de Araujo. "Inactivation of maltose permease and maltase in sporulatingSaccharomyces cerevisiae." Canadian Journal of Microbiology 46, no. 4 (April 1, 2000): 383–86. http://dx.doi.org/10.1139/w99-136.
Abstract:
Maltose transport and maltase activities were inactivated during sporulation of a MAL constitutive yeast strain harboring different MAL loci. Both activities were reduced to almost zero after 5 h of incubation in sporulation medium. The inactivation of maltase and maltose permease seems to be related to optimal sporulation conditions such as a suitable supply of oxygen and cell concentration in the sporulating cultures, and occurs in the fully derepressed conditions of incubation in the sporulation acetate medium. The inactivation of maltase and maltose permease under sporulation conditions in MAL constitutive strains suggests an alternative mechanism for the regulation of the MAL gene expression during the sporulation process.Key words: maltase activity, maltose permease activity, sporulation, Saccharomyces cerevisiae.
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Ozsarac, N., M. J. Straffon, H. E. Dalton, and I. W. Dawes. "Regulation of gene expression during meiosis in Saccharomyces cerevisiae: SPR3 is controlled by both ABFI and a new sporulation control element." Molecular and Cellular Biology 17, no. 3 (March 1997): 1152–59. http://dx.doi.org/10.1128/mcb.17.3.1152.
Abstract:
The SPR3 gene encodes a sporulation-specific homolog of the yeast Cdc3/10/11/12 family of bud neck filament proteins. It is expressed specifically during meiosis and sporulation in Saccharomyces cerevisiae. Analysis of the sporulation-specific regulation of SPR3 has shown that it is strongly activated under sporulating conditions but shows low levels of expression under nonsporulating conditions. A palindromic sequence located near the TATA box is essential to the developmental regulation of this gene and is the only element directly activating SPR3 at the right time during sporulation. Within the palindrome is a 9-bp sequence, gNCRCAAA(A/T) (midsporulation element [MSE]), found in the known control regions of three other sporulation genes. A previously identified ABFI element is also needed for activation. The MSE has been shown to activate a heterologous promoter (CYC1) in a sporulation-specific manner. Related sequences, including an association of MSE and ABFI elements, have been found upstream of other genes activated during the middle stage of S. cerevisiae sporulation. One group of these may be involved in spore coat formation or maturation.
3
Eswaramoorthy, Prahathees, Jeffrey Dinh, Daniel Duan, Oleg A. Igoshin, and Masaya Fujita. "Single-cell measurement of the levels and distributions of the phosphorelay components in a population of sporulating Bacillus subtilis cells." Microbiology 156, no. 8 (August 1, 2010): 2294–304. http://dx.doi.org/10.1099/mic.0.038497-0.
Abstract:
Upon nutrient starvation, the Gram-positive bacterium Bacillus subtilis switches from growth to sporulation by activating a multicomponent phosphorelay consisting of a major sensor histidine kinase (KinA), two phosphotransferases (Spo0F and Spo0B) and a response regulator (Spo0A). Although the primary sporulation signal(s) produced under starvation conditions is not known, it is believed that the reception of a signal(s) on the sensor kinase results in the activation of autophosphorylation of the enzyme. The phosphorylated kinase transfers the phosphate group to Spo0A via the phosphorelay and thus triggers sporulation. With a combination of quantitative immunoblot analysis, microscopy imaging and computational analysis, here we found that each of the phosphorelay components tested increased gradually over the period of sporulation, and that Spo0F was expressed in a more heterogeneous pattern than KinA and Spo0B in a sporulating cell population. We determined molecule numbers and concentrations of each phosphorelay component under physiological sporulation conditions at the single-cell level. Based on these results, we suggest that successful entry into the sporulation state is manifested by a certain critical level of each phosphorelay component, and thus that only a subpopulation achieves a sufficient intracellular quorum of the phosphorelay components to activate Spo0A and proceed successfully to the entry into sporulation.
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Eswaramoorthy, Prahathees, Daniel Duan, Jeffrey Dinh, Ashlee Dravis, Seram Nganbiton Devi, and Masaya Fujita. "The Threshold Level of the Sensor Histidine Kinase KinA Governs Entry into Sporulation in Bacillus subtilis." Journal of Bacteriology 192, no. 15 (May 28, 2010): 3870–82. http://dx.doi.org/10.1128/jb.00466-10.
Abstract:
ABSTRACT Sporulation in Bacillus subtilis is controlled by a complex gene regulatory circuit that is activated upon nutrient deprivation. The initial process is directed by the phosphorelay, involving the major sporulation histidine kinase (KinA) and two additional phosphotransferases (Spo0F and Spo0B), that activates the master transcription factor Spo0A. Little is known about the initial event and mechanisms that trigger sporulation. Using a strain in which the synthesis of KinA is under the control of an IPTG (isopropyl-β-d-thiogalactopyranoside)-inducible promoter, here we demonstrate that inducing the synthesis of the KinA beyond a certain level leads to the entry of the irreversible process of sporulation irrespective of nutrient availability. Moreover, the engineered cells expressing KinA under a σH-dependent promoter that is similar to but stronger than the endogenous kinA promoter induce sporulation during growth. These cells, which we designated COS (constitutive sporulation) cells, exhibit the morphology and properties of sporulating cells and express sporulation marker genes under nutrient-rich conditions. Thus, we created an engineered strain displaying two cell cycles (growth and sporulation) integrated into one cycle irrespective of culture conditions, while in the wild type, the appropriate cell fate decision is made depending on nutrient availability. These results suggest that the threshold level of the major sporulation kinase acts as a molecular switch to determine cell fate and may rule out the possibility that the activity of KinA is regulated in response to the unknown signal(s).
5
Caffi, Tito, Giovanna Gilardi, Matteo Monchiero, and Vittorio Rossi. "Production and Release of Asexual Sporangia in Plasmopara viticola." Phytopathology® 103, no. 1 (January 2013): 64–73. http://dx.doi.org/10.1094/phyto-04-12-0082-r.
Abstract:
To study the influence of environmental conditions on sporulation of Plasmopara viticola lesions under vineyard's conditions, unsprayed vines were inspected every second or third day and the numbers of sporulating and nonsporulating lesions were counted in two North Italy vineyards in 2008 to 2010. Infected leaves were removed so that only fresh lesions were assessed at each field assessment. Sporulation was studied at two scales, across field assessments and across the seasonal population of lesions. Frequencies of sporulating lesions were positively correlated with the numbers of moist hours in the preceding dark period (i.e., the number of hours between 8:00 p.m. and 7:00 a.m. with relative humidity ≥80%, rainfall >0 mm, or wetness duration >30 min). In a receiver operating characteristic analysis, predicted sporulation based on the occurrence of ≥3 moist hours at night provided overall accuracy of 0.85. To study the time course of sporulation on lesions which were not washed by rainfall, numbers of sporangia produced per square millimeter of lesion were estimated on individual cohorts of lesions over the whole infectious period. The numbers of sporangia per square millimeter of lesion increased rapidly during the first 4 days after the beginning of sporulation and then tapered off prior to a halt; the time course of cumulative sporangia production by a lesion followed a monomolecular growth model (R2 = 0.97). The total number of sporangia produced by a square millimeter of lesion increased as the maximum temperature decreased and moist hours in the dark increased. To study the release pattern of the sporangia, spore samplers were placed near grapevines with sporulating lesions. Airborne sporangia were caught in 91.2% of the days over a wide range of weather conditions, including rainless periods. The results of this study provide quantitative information on production of P. viticola sporangia that may help refine epidemiological models used as decision aids in grape disease management programs.
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Olempska-Beer, Z., and E. Freese. "Initiation of meiosis and sporulation in Saccharomyces cerevisiae does not require a decrease in cyclic AMP." Molecular and Cellular Biology 7, no. 6 (June 1987): 2141–47. http://dx.doi.org/10.1128/mcb.7.6.2141-2147.1987.
Abstract:
Meiosis and sporulation of Saccharomyces cerevisiae are initiated in a guanine auxotroph by guanine deprivation (E. Bautz Freese, Z. Olempska-Beer, A. Hartig, and E. Freese, Dev. Biol. 102:438-451, 1984). We used this condition to examine a hypothesis (K. Matsumoto, I. Uno, and T. Ishikawa, Cell 32:417-423, 1983) that initiation of meiosis requires a low level of cAMP. We found that, after guanine deprivation, the intracellular concentration of cAMP transiently decreased not more than 20% and not at all if the cAMP phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX) was added to the medium. Under these conditions, at least 76% of the cells sporulated in the absence of IBMX, and almost 100% sporulated in its presence. The sporulating cells continually excreted cAMP and utilized the gluconeogenic carbon source. The cells failed to sporulate efficiently and to form four-spored asci if simultaneously deprived of guanine and carbon. After guanine deprivation in glucose medium, sporulation remained suppressed and intracellular cAMP was unchanged. We conclude that, under conditions of guanine starvation, cAMP deficiency is not required for initiation of meiosis and sporulation, cAMP is produced in excess and excreted to the medium, the cells sporulate better if the cAMP concentration is increased by addition of IBMX, the cells require a gluconeogenic carbon source for complete and efficient sporulation, and suppression of sporulation by glucose is not mediated by cAMP.
7
Olempska-Beer, Z., and E. Freese. "Initiation of meiosis and sporulation in Saccharomyces cerevisiae does not require a decrease in cyclic AMP." Molecular and Cellular Biology 7, no. 6 (June 1987): 2141–47. http://dx.doi.org/10.1128/mcb.7.6.2141.
Abstract:
Meiosis and sporulation of Saccharomyces cerevisiae are initiated in a guanine auxotroph by guanine deprivation (E. Bautz Freese, Z. Olempska-Beer, A. Hartig, and E. Freese, Dev. Biol. 102:438-451, 1984). We used this condition to examine a hypothesis (K. Matsumoto, I. Uno, and T. Ishikawa, Cell 32:417-423, 1983) that initiation of meiosis requires a low level of cAMP. We found that, after guanine deprivation, the intracellular concentration of cAMP transiently decreased not more than 20% and not at all if the cAMP phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX) was added to the medium. Under these conditions, at least 76% of the cells sporulated in the absence of IBMX, and almost 100% sporulated in its presence. The sporulating cells continually excreted cAMP and utilized the gluconeogenic carbon source. The cells failed to sporulate efficiently and to form four-spored asci if simultaneously deprived of guanine and carbon. After guanine deprivation in glucose medium, sporulation remained suppressed and intracellular cAMP was unchanged. We conclude that, under conditions of guanine starvation, cAMP deficiency is not required for initiation of meiosis and sporulation, cAMP is produced in excess and excreted to the medium, the cells sporulate better if the cAMP concentration is increased by addition of IBMX, the cells require a gluconeogenic carbon source for complete and efficient sporulation, and suppression of sporulation by glucose is not mediated by cAMP.
8
Poletto, Tales, Marlove F. B. Muniz, Vinícius S. Fantinel, Renata F. Favaretto, Igor Poletto, Lia R. S. Reiniger, and Elena Blume. "Culture Medium, Light Regime and Temperature Affect the Development of Sirosporium diffusum." Journal of Agricultural Science 10, no. 6 (May 6, 2018): 310. http://dx.doi.org/10.5539/jas.v10n6p310.
Abstract:
Sirosporium diffusum is the causal agent of the brown leaf spot disease on pecan trees that seriously damages the foliage of adult plants and seedlings. This fungal species is difficult to grow satisfactorily in a culture medium. Therefore, the aim of this study was to evaluate the effects of different physical conditions on the development of S. diffusum. In the first assay, eight culture media and five light regimes were combined, while in the second, the three treatments that promoted highest sporulation were combined with three temperatures. The trials were conducted in a two-factorial arrangement in a fully randomized design with six replicates. V8, V8CaCO3, and CA media under a 24-h photoperiod produced the highest respective sporulations: 29 × 104, 35 × 104, and 41 × 104 conidia ml-1. The best temperature for sporulation was 20±1 °C for all culture media, especially V8CaCO3 and CA. The best artificial conditions for obtaining good mycelial growth and sporulation consisted of a photoperiod of 24 h, temperature of 20±1 °C and V8CaCO3 or CA culture medium.
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FAILLE, CHRISTINE, JEANNE MARIE MEMBRE, MARTINE KUBACZKA, and FRANÇOISE GAVINI. "Altered Ability of Bacillus cereus Spores To Grow under Unfavorable Conditions (Presence of Nisin, Low Temperature, Acidic pH, Presence of NaCl) following Heat Treatment during Sporulation." Journal of Food Protection 65, no. 12 (December 1, 2002): 1930–36. http://dx.doi.org/10.4315/0362-028x-65.12.1930.
Abstract:
The effect of thermal treatment on the heat resistance of Bacillus cereus spores and their ability to germinate and grow under more or less adverse conditions during sporulation was investigated. Spores produced by sporulating cells subjected to a mild heat treatment (at a temperature 15°C higher than the growth temperature) were more resistant to heat than were spores produced by untreated cells. Spore germination and growth (the lag time, the maximal growth rate, and the occurrence of a decrease in population) may be greatly affected by adverse environmental conditions brought about by the addition of nisin, low temperatures, acidic pHs, and, to a lesser extent, the addition of NaCl. Furthermore, heat treatments applied to sporulating cells or to mature spores induced a modification of the lag time (interaction of both treatments). Therefore, mild heat treatments applied during sporulation may affect the heat resistance of spores and the ability of these spores to germinate under adverse conditions and may thus increase the risk associated with the presence of spores in lightly processed foods.
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Kaback, D. B., and L. R. Feldberg. "Saccharomyces cerevisiae exhibits a sporulation-specific temporal pattern of transcript accumulation." Molecular and Cellular Biology 5, no. 4 (April 1985): 751–61. http://dx.doi.org/10.1128/mcb.5.4.751-761.1985.
Abstract:
Cultures of the yeast Saccharomyces cerevisiae that are heterozygous for the mating type (MATa/MAT alpha) undergo synchronous meiosis and spore formation when starved for nitrogen and supplied with a nonfermentable carbon source such as acetate. Haploid and homozygous MAT alpha/MAT alpha and MATa/MATa diploid cells incubated under the same conditions fail to undergo meiosis and are asporogenous. It has not yet been firmly established that gene expression during sporulation is controlled at the level of transcript accumulation. To examine this question, we used cloned genes that encode a variety of "housekeeping" functions to probe Northern blots to assay the appearance of specific transcripts in both sporulating and asporogenous S. cerevisiae. In sporulating cells, each transcript showed a characteristic pattern of accumulation, reaching a maximum relative abundance at one of several different periods. In contrast, in both asporogenous haploid MATa and diploid MAT alpha/MAT alpha cells, all transcripts accumulated with similar kinetics. These results suggest a sporulation-specific pattern for transcript appearance. During these studies, high levels of several different transcripts were observed at unexpected times in sporulating cells. Histone (H)2A and (H)2B1 transcripts, although most abundant during premeiotic DNA synthesis, remained at one-third to one-half maximal levels after its end and were found in mature ascospores. Their appearance at this time is in sharp contrast to vegetative cells in which these histone transcripts are only found just before and during the period of DNA synthesis. Furthermore, transcripts from GAL10 and CDC10 genes, which are believed to be dispensable for sporulation, were much more abundant in sporulating cells than in asporogenous cells and vegetative cells grown on glucose or acetate. The presence of these transcripts did not appear to be due to a general activation of transcription because each accumulated with different kinetics. In addition, the transcript for at least one gene, HO, that is also dispensable for sporulation was not detected. The increased abundance of transcripts from some genes not required for sporulation leads us to propose that genes preferentially expressed during sporulation need not be essential for this differentiation.
Dissertations / Theses on the topic "Sporulation conditions":
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Payot-Lacroix, Sophie. "Etude des conditions physiologiques influençant] la croissance, le catabolisme du cellobiose et la sporulation de Clostridium Cellulolytycum ATCC 35319." Nancy 1, 1999. http://docnum.univ-lorraine.fr/public/SCD_T_1999_0266_PAYOT.pdf.
Abstract:
Des cultures en chémostat de Clostridium cellulolyticum ont été mises en oeuvre en présence de cellobiose comme source principale de carbone. Sur milieu complexe, le profil de fermentation, orienté majoritairement vers la production d'acétate, conduit à un défaut de régénération du NADH. Il en résulte une accumulation de ce coenzyme réduit qui pourrait limiter la croissance bactérienne en inhibant l'activité glycéraldéhyde-3-P-déshydrogénase. Sur milieu synthétique, la mise en place de régulations particulières (induction de la production de lactate notamment) permet de diminuer le rapport NADH/NAD+ et d'augmenter la vitesse de consommation de cellobiose. Une induction de la production de lactate est également obtenue lors de cultures en batch de C. Cellulolyticum sur milieu complexe, à pH régulé avec une concentration de cellobiose élevée. Cette induction permet une reprise de la croissance bactérienne en favorisant la régénération du NADH, doublant ainsi la biomasse bactérienne finale obtenue. L'étude des conditions de sporuIation de C. Cellulolyticum a permis de montrer que ce processus (i) est dépendant de la vitesse de croissance de la bactérie, (ii) n'est pas déclenché par une carence en cellobiose ou ammonium et (iii) est soumis à une répression catabolique par le cellobiose. Un gène codant pour une rubrédoxine, protéine fer-soufre qui pourrait servir de transporteur d'électrons, a été mis en évidence chez C. Cellulolyticum. L'analyse de ce gène et des variations de la teneur des cellules en rubrédoxine a permis (i) de mettre en évidence des signaux caractéristiques de transcription et de traduction, (ii) de réfuter certaines hypothèses concernant le rôle de cette protéine (notamment dans la résistance à certains stress).
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Payot-Lacroix, Sophie Petitdemange Henri. "Etude des conditions physiologiques influançant [i.e. influençant] la croissance, le catabolisme du cellubiose et la sporulation de Clostridium Cellulolyticum ATCC 35319." [S.l.] : [s.n.], 1999. http://www.scd.uhp-nancy.fr/docnum/SCD_T_1999_0266_PAYOT.pdf.
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Hamiot, Audrey. "Crust des spores de Bacillus subtilis : voies de biosynthèse et influence des conditions de sporulation sur sa structure et les propriétés de surface des spores." Electronic Thesis or Diss., Université de Lille (2022-....), 2023. http://www.theses.fr/2023ULILR033.
Abstract:
Les bactéries du groupe Bacillus subtilis sont des bactéries sporulantes responsables de contamination récurrentes au sein des industries agro-alimentaires. La capacité des spores de B. subtilis à résister à des conditions environnementales extrêmes et à adhérer aux surfaces explique la persistance de ces bactéries au sein des chaines de transformation. Chez B. subtilis, la couche la plus externe des spores est le crust. Le crust est composé de protéines et de glycanes et il confère aux spores leur propriétés de surface et d'adhésion. Dans cette thèse, nous nous sommes intéressés aux gènes impliqués dans la biosynthèse des glycanes du crust. Nous avons mis en évidence que les gènes spsM et spsCDEFG codent les enzymes formant la voie de biosynthèse de l'acide legionaminique (Leg), un acide nonulosonique nécessaire à l'assemblage du crust. En absence de Leg, les spores sont plus hydrophobes, plus adhérentes et moins chargées à leur surface. Nous avons également montré que les gènes cgeB et cgeD, qui codent des glycosyltransférases putatives, sont nécessaires à la formation du crust. Les mutants de ces gènes produisent des spores qui sont plus hydrophobes et plus adhérentes et leur crust contient moins de rhamnose et d'acide legionaminique. Le second objectif de cette thèse a été d'étudier l'impact des conditions de sporulations sur les propriétés de surface et d'adhésion des spores. Nous avons montré qu'une carence en cation divalents (Ca2+ ou Mg2+), une disponibilité en oxygène réduite, la présence d'agents oxydants ou un environnement acide lors de la sporulation entrainent la production de spores plus hydrophobes et adhérentes. Nous avons démontré que ces modifications des propriétés de surface sont généralement associées à des modifications de la structure et/ou de la composition du crust. Le crust des spores produites dans un milieu de sporulation carencé en Ca2+ ou Mg2+ ou dans des conditions d'oxygénation réduite contiennent des quantités plus faibles de rhamnose et d'acide légionaminique. Nous avons également montré qu'une plus faible disponibilité en oxygène ou l'ajout de peroxyde d'hydrogène pendant la sporulation diminue la quantité de deux protéines du crust (CgeA et CotY) et que les changements observés dans ces conditions pourraient être dus à la répression de la transcription des gènes impliqués dans la synthèse du crust en phase stationnaire tardive. Le fait que les conditions de sporulation affectent la facilité avec laquelle les spores contaminent les surfaces pourrait expliquer la récurrence de la contamination des chaînes de transformation alimentaire par les spores de B. subtilisBacillus subtilis are spore-forming bacteria responsible for recurrent contamination in the food industry. The ability of B. subtilis spores to resist extreme environmental conditions and to adhere to surfaces explains the persistence of these bacteria in processing plants. In B. subtilis the outermost layer of the spores is the crust. The crust is composed of proteins and glycans and gives the spores their surface and adhesion properties. In this study we investigated the genes involved in the crust glycans biosynthesis. We have shown that the spsM and spsCDEFG genes encode the enzymes forming the biosynthesis pathway of legionaminic acid (Leg), a nonulosonic acid required for crust assembly. In absence of Leg, spores are more hydrophobic, more adherent and less charged on their surface. We also demonstrated that the genes cgeB and cgeD encode putative glycosyltransferases required for crust biosynthesis. Mutants of these genes produce spores that are more hydrophobic and adherent and their crust contains less rhamnose and legionaminic acid. The second objective of this study was to investigate the effect of sporulation conditions on the surface and adhesion properties of spores. We have shown that a depletion in divalent cation, a lower oxygen availability, the presence of oxidizing agents or an acidic environment during sporulation lead to the production of more adherent and hydrophobic spores. We have shown that these changes in surface properties are generally associated with changes in crust structure and/or composition. The crust of spores produced in a Ca2+ or Mg2+ deficient sporulation medium or under reduced oxygenation conditions contain lower amounts of rhamnose and legionaminic acid. We also showed that lower oxygen availability or the addition of hydrogen peroxide during sporulation decreases the amount of two crust proteins (CgeA and CotY) and that the changes observed under these conditions could be due to the repression of transcription of genes involved in late stationary phase crust synthesis. The fact that sporulation conditions affect the ease with which spores contaminate surfaces could explain the recurrence of contamination of food processing chains by B. subtilis spores
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Larroche, Christian. "Analyse du développement d'un champignon filamenteux par l'élaboration des bilans matières et ATP interprétés par une approche stoechiométrique : Application à la croissance et à la sporulation d'un champignon filamenteux dans des conditions de culture en milieu solide." Clermont-Ferrand 2, 1990. http://www.theses.fr/1990CLF2E431.
Abstract:
La croissance et la sporulation de penicillium roquefortii cultive dans des conditions de fermentation en milieu solide sont etudiees a travers l'etablissement des bilans matiere, thermique et bioenergetique. Deux techniques de mise en uvre sont envisagees; la premiere repose sur l'utilisation d'un substrat amylace particulaire constitue de grains de sarrasin, la seconde consiste en l'emploi d'un support mineral poreux compose de particules de pouzzolane, impregnees et continuellement alimentees en milieu nutritif liquide concentre. Les conditions de mise en uvre d'une culture sur substrat naturel sont determinees a l'aide d'une procedure dite plan factoriel 2#3 a deux niveaux realisee en utilisant un microfermenteur; les protocoles d'utilisation d'un fermenteur rotatif et d'un reacteur colonne a lit fixe sont precises. L'ecriture des equations stoechiometriques relatives aux differentes phases du developpement du microorganisme sur sarrasin permet d'analyser les echanges observes. L'interpretation des resultats experimentaux suggere l'introduction d'un concept prevoyant la presence de deux gradients d'activite de l'eau, un entre le mycelium et le substrat, l'autre entre le mycelium et les structures de differenciation. La determination des flux d'atp, menee en utilisant une methode simplifiee originale, permet d'atteindre le rapport p/o qui se revele un parametre predictif du comportement du microorganisme. La maximalisation de l'efficacite de sporulation impose d'obtenir des conditions de culture permettant d'obtenir un rapport p/o faible, proche de 1,56
Books on the topic "Sporulation conditions":
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Smith, Robert M. Other bacterial diseasesErysipeloid. Oxford University Press, 2011. http://dx.doi.org/10.1093/med/9780198570028.003.0025.
Abstract:
Erysipeloid is an acute bacterial infection usually causing acute localised cellulitis as a secondary infection of traumatised skin. It is caused by Erysipelothrix rhusiopathiae (insidiosa), a non-sporulating Gram-positive rod-shaped bacterium, ubiquitous in the environment. It is the cause of swine erysipelas and also a pathogen or commensal in a variety of wild and domestic birds, animal and marine species. Human infection primarily associated with occupational exposure to infected or contaminated animals or handling animal products and therefore is commoner in farmers, butchers and abattoir workers and fisherman.Risk factors for the rare human invasive E. rhusiopathiae infection include conditions that affect the host immune response, such as alcoholism, cancer and diabetes. Treatment is with penicillin.Erysipelas can affect animals of all ages but is recognised more frequently in juveniles. Swine exhibit similar stages to the disease in man. Clinical manifestations in swine vary from the classical rhomboid urticaria (diamond skin), the condition of greatest prevalence and economic importance, to sepsis, polyarthritis, pneumonia and death.Prevention is largely a matter of good hygiene, herd management and by raising awareness in those at risk (especially butchers, farmers and fishermen); ensuring that clinicians are aware of E. rhusiopathiae as a possible cause of occupational skin lesions and bacterial endocarditis is important.
Book chapters on the topic "Sporulation conditions":
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Elrod, Susan L., Sabrina M. Chen, Katja Schwartz, and Elizabeth O. Shuster. "Optimizing Sporulation Conditions for Different Saccharomyces cerevisiae Strain Backgrounds." In Methods in Molecular Biology, 21–26. Totowa, NJ: Humana Press, 2009. http://dx.doi.org/10.1007/978-1-59745-527-5_2.
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Guochang, Sun, and Sun Shuyuan. "Conditions for Sporulation and Preservation of Conidia of Rice Blast Fungus Pyricularia Grisea." In Major Fungal Diseases of Rice, 111–17. Dordrecht: Springer Netherlands, 2001. http://dx.doi.org/10.1007/978-94-017-2157-8_8.
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Stevens, T. H. "Saccharomyces cerevisiae Eug1." In Guidebook to Molecular Chaperones and Protein-Folding Catalysts, 339–40. Oxford University PressOxford, 1997. http://dx.doi.org/10.1093/oso/9780198599494.003.00130.
Abstract:
Abstract EUG1 (ER protein unnecessary for growth under standard laboratory conditions) was named for its observed mutant phenotype (Tachibana, Stevens, 1992). Overproduction or deletion of the EUG1 gene appears to have no effect on cell viability or function. Yeast cells deleted for EUG1 grow with wild-type rates on rich or minimal media at temperatures from 18 to 40°C, can grow anaerobically. Sporulation is not affected in homozygous eug1& cells, nor is the transport of vacuolar, secreted proteins through the secretory pathway.
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Ekena, K., M. LaMantia,, and T. Steven. "EUG1." In Secretory Pathway, 45–46. Oxford University PressOxford, 1994. http://dx.doi.org/10.1093/oso/9780198599425.003.0029.
Abstract:
Abstract EUG1 (I;R protein necessary for growth under standard laboratory conditions) was named for its observed mutant phenotype. Overproduction or deletion of the EUG1 gene appears to have no effect on cell viability or function. Yeast cells deleted for EUG1 grow with wild-type rates on rich or minimal media at temperatures from 18°( to 40°( and can grow anaerobically. Sporulation is not affected in homozygous eug1t,, cells, nor is the transport of vacuolar and secreted proteins through the secretory pathway. Finally, eug1 cells do not exhibit any increased sensitivity or requirement for calcium.
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Boylan, S. A., S. Kalman, M. L. Duncan, S. M. Thomas, and C. W. Price. "TWO GENES DEPENDENT ON BACILLUS SUBTILIS σB ARE EXPRESSED IN STATIONARY PHASE UNDER NON-SPORULATING CONDITIONS." In Genetics and Biotechnology of Bacilli, 377–84. Elsevier, 1990. http://dx.doi.org/10.1016/b978-0-12-274162-3.50044-x.
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Pappas, Peter G. "Sporotrichosis." In Clinical Mycology, 346–54. Oxford University PressNew York, NY, 2003. http://dx.doi.org/10.1093/oso/9780195148091.003.0022.
Abstract:
Abstract Sporotrichosis is a chronic pyogranulomatous infection caused by the thermally dimorphic fungus Sporothrix schenckii. Infection is usually limited to the skin and subcutaneous tissues, but can involve virtually any organ in its disseminated form. Less common localized forms of sporotrichosis include arthritis, osteomyelitis, meningitis, chronic pulmonary infection, and ocular disease. Schenck originally described sporotrichosis in 1898 in a 36-year old man who presented with several discrete indurated lesions extending along the lymphatics from the index finger proximally to the forearm. The organism obtained from cultures of the purulent drainage from one of these lesions revealed heavy growth of a moderately rapidly growing fungus that he designated as possibly related to Sporotrichum spp. (Schenck, 1898). Subsequently, investigators reported a second case of sporotrichosis in a 5-year-old boy with chronic ulceration of the index finger and associated nodular lymphangitis of the forearm (Hektoen and Perkins, 1900). Treatment entailed serial incision and drainage of each subcutaneous nodule followed by local wound care resulting in eventual full recovery. The fungus isolated from this young patient was referred to as Sporothrix schenckii. However, the more common designation, Sporotrichum schenckii, was used through the late 1960s until Carmichael’s observation that the organism had a different manner of sporulation when compared to Sporotrichum spp., and the name Sporothrix schenckii was officially readopted (Carmichael, 1962). After the initial description of sporotrichosis, most early cases were reported from France. One of the case reviews from France involved approximately 250 patients with sporotrichosis and remains one of the largest reports of this condition to date (de Beurman and Gougerot, 1912). As knowledge of the disease became more widespread, fewer cases were identified in Europe and cases of sporotrichosis began to be reported world-wide, with the abundance of cases emerging from the United States, Mexico, and South America.
Conference papers on the topic "Sporulation conditions":
1
Safiullin, R. T., and E. I. Chalysheva. "CULTURE OF EIMERIA SPP. OOCYSTS OF TURKEY POULTS AND THEIR SPECIES IDENTIFICATION." In THEORY AND PRACTICE OF PARASITIC DISEASE CONTROL. All-Russian Scientific Research Institute for Fundamental and Applied Parasitology of Animals and Plant – a branch of the Federal State Budget Scientific Institution “Federal Scientific Centre VIEV”, 2023. http://dx.doi.org/10.31016/978-5-6048555-6-0.2023.24.414-419.
Abstract:
In our country, in recent years, much attention has been paid to the development of
poultry meat production, especially turkey breeding. In the conditions of industrial
turkey breeding, when a large number of poultry is kept in a limited area, there is a
high risk of parasitic diseases, one of which is eimeriosis. Knowledge of the species
composition of Eimeria on a particular poultry farm is of great practical importance
for the reasonable development of effective methods to control invasion and to
monitor Eimeria resistance to the drugs used. Eimeria species were identified after
the end of sporulation. To assess the course of sporulation of Eimeria oocysts during
their cultivation, at least 500 oocysts were examined from each Petri dish every six
hours under a high magnification microscope (x400) paying special attention to
their morphology. When examining and studying litter samples 24 hours after they
were put on cultivation, sporulated Eimeria oocysts of turkeys were detected in all six
dishes in 37.8% to 60.6% of those examined, and the average rate was 51.6%. At 48
hours after the start of cultivation, the average Eimeria sporulation rate was 83.4%.
The results of species identification of Eimeria oocysts showed that the following
Eimeria species were found in young turkeys on the poultry farm of the Tula Region:
Eimeria meleagrimitis (60.0%), E. gallopavonis (25.0%), E. meleagridis (10.0%), and
E. adenoides (5.0%).
2
Lungu, Andrei. "Some features of cultivation of the actinobacterium saccharopolyspora spinosa." In 5th International Scientific Conference on Microbial Biotechnology. Institute of Microbiology and Biotechnology, Republic of Moldova, 2022. http://dx.doi.org/10.52757/imb22.22.
Abstract:
Purpose: Actinobacteria (actinomycetes) are in the center of attention because these bacteria produce a variety of natural drugs and other biologically active metabolites, including: antibiotics, enzymes, inhibitors. More than 22,000 biologically active secondary metabolites (including antibiotics) produced by microorganisms have been identified and published in the literature and patented. About half of these compounds are produced by actinomycetes. Currently, about 160 antibiotics are used in medicine and agriculture, 100-120 of these compounds, including streptomycin, erythromycin, gentamicin, vancomycin, vermectin, etc. are produced by actinomycetes. However, the use of actinomycetes for the development of new methods and means is increasingly difficult. Although a large number of microorganisms have been identified, described, verified, more than 90% of all microorganisms remain unutilized. These species could be used intensively to obtain new means, which would contribute to a sustainable development of human society [D. Dhanasekaran, 2016]. Spinosins are new macrolides, natural metabolites produced under aerial fermentation conditions by the species Saccharopolyspora spinosa. These compounds contain a unique system of tetracyclic rings to which two sugar residues are attached. Spinosad, a mixture of spinosyns A and D, is used as a unique pesticide with high selective activity against target pests and low toxicity in non-target organisms (including many beneficial arthropods). These characteristics make spinosad a good new tool for integrated pest management. The discovery and characterization of S. spinosa represents a new opportunity to develop progressive insect management tools using native products [MERTZ, and YAO, 1990], [Guojun Y, 2016]. Materials and Method: The strain Saccharopolyspora spinosa DSM-44228 was used for the experiments. Cultivation was carried out in the initial stages on agar medium and then moved to deep cultivation on liquid medium. We developed and used several compositions of the liquid medium, quantitative changes were made to the components and it was used several sources of carbon and nitrogen. In the same way, the cultivation time, temperature, pH of the culture medium was changed in all variants, the rocking shaker has 150 r/m. As a carbon source, it was used glucose, sucrose, and maltose. As an alternative source it was used also soy, corn, and sunflower flour. Results: So far we have been able to achieve good growth and sporulation over 7 days on agar medium. On liquid medium we have developed two compositions on which there was a good accumulation of biomass, but they have not yet been determined the amount of produced Spinosad. We are going to carry out the optimization of the medium to achieve a maximum possible production of biomass.
Reports on the topic "Sporulation conditions":
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Sanabria, Johana, Ginna Quiroga, Cindy Mejía, Erika Grijalba, and Martha Goméz. Effect of abiotic factors on viability and characterization of Metarhizium rileyi Nm017. Corporación colombiana de investigación agropecuaria - AGROSAVIA, 2019. http://dx.doi.org/10.21930/agrosavia.poster.2019.18.
Abstract:
The species Chloridea virescens and Helicoverpa zea (Lepidoptera: Noctuidae) are declared agricultural pests with a high economic impact worldwide (Angulo et al. 2008). They are widely distributed on the American continent, and agrochemical are the most common method to control, which can cause environmental, social, economic and public impacts. A strain of Metarhizium rileyi Nm017 [AGROSAVIA - Orinoquia area (Col.)], demonstrated an e cacy of 75.8% on C. virescens, and 92.5% on H. zea on laboratory conditions. Mass production and virulence of Metarhizium sp. are susceptible to stress conditions such as temperature, UVB radiation and pH, a ecting conidial vigor, germination, and sporulation (Rangel et al. 2008, Oliveira et al. 2016). Likewise, the culture medium can a ect the infection processes measured through hydrophobicity and enzymatic activities (Ortiz 2013). The identi cation of these parameters allows selecting the most favorable conditions for its production and the challenges that must be assumed in downstream processes.
2
Israel, Alvaro, and John Merrill. Production of Seed Stocks for Sustainable Tank Cultivation of the Red Edible Seaweed Porphyra. United States Department of Agriculture, 2006. http://dx.doi.org/10.32747/2006.7696527.bard.
Abstract:
Porphyra species (commonly known as ‘nori’ or ‘purple laver’) are edible red seaweeds rich in proteins, vitamins and other highly valued biogenic compounds. For years Porphyra has been cultured using seeded nets extended in the open sea, and its biomass consumed primarily in the Far East. While demands for international markets have increased steadily at an average of 20% per year, supplies are on the verge and not expected to meet future demands. Alternatively, land-based cultivation of seaweed has become attractive in the mariculture industry since (1) important growth parameters can be controlled, (2) is environmentally friendly and (3) perfectly matches with integrated aquaculture leading to sustainable, high quality products. During the last few years a tank cultivation technology for Porphyra has been developed at the Israeli institution. This technology is based on indoor production of asexual spores and their subsequent growth to 1-2 mm seedlings. The seedlings are then transferred to outdoor tanks and ponds when seawater temperatures drop to 20 °C, or below, and days become shorter during winter time. However, the current technology efficiently serves only about 100 m2 of ponds during one growth season. In order to produce seedlings in sufficient amounts, it is critical to address both technical and biological aspects of seedling production, securing optimal up-scale to commercial-size cultivation farms. We hypothesize that massive production of spores is related to thalli origin, thalli age and sporulation triggers, and that seedling survival and their subsequent growth potential is determined by the seawater quality and overall indoor growth conditions imposed. A series of bio-reactors were constructed and tested in which spore release and spore growth were separately studied. The main assessment criteria for optimal viability of the seedlings will be by determining their electron transport rate using PAM fluorometry and by subsequent growth and biomass yields in outdoor ponds. Altogether the project showed (1), controlled sporulation is possible in big outdoor/growth chamber settings provided initial stock material (small frozen seedlings) is at hand, (2), contamination problems can be almost completely avoided if stock material is properly handled (clean as possible and partially dehydrated prior to freezing), (3), spore release can significantly be enhance using high nutrient levels during thawing for P. yezoensis and P. haitanensis, but not for P. rosengurttii, (4), PAM fluorometry is an efficient tool to estimate growth capacity in both seedlings and juvenile thalli. The BARD funding also served to explore other aspects of Porphyra biology and cultivation. For example, the taxonomical status of Porphyra strains used in this study was defined (see appendix), and the potential use of this seaweed in bioremediation was well substantiated. In addition, BARD funding supported a number of opportunities and activities in the Israeli lab, direct or indirectly related to the initial objectives of the project such as: additional molecular work in other seaweeds, description of at least 2 new species for the Israeli Mediterranean, and continuous support for the writing of a book on Global Change and applied aspects of seaweeds. The technology for Porphyra cultivation in land-based ponds is readily available. This study corroborated previous know-how of Porphyra growth in tanks and ponds, and yet offers important improvements regarding seedling production and their handling for successful cultivation. This study supported various other activities opening additional important issues in the biology/cultivation/use of Porphyra and other seaweeds.