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Journal articles on the topic 'Bacteria accumulation'

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Author: Grafiati
Published: 10 December 2022
Last updated: 28 January 2023

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1

Bordons, Albert, and Joan Jofre. "Nickel accumulation by bacteria." Environmental Technology Letters 8, no. 1-12 (January 1987): 495–500. http://dx.doi.org/10.1080/09593338709384511.

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2

Van Dyke, Michele I., Hung Lee, and Jack T. Trevors. "Germanium accumulation by bacteria." Archives of Microbiology 152, no. 6 (November 1989): 533–38. http://dx.doi.org/10.1007/bf00425482.

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3

Lacko, N., G. D. Drysdale, and F. Bux. "Anoxic phosphorus removal by denitrifying heterotrophic bacteria." Water Science and Technology 47, no. 11 (June 1, 2003): 17–22. http://dx.doi.org/10.2166/wst.2003.0581.

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The unexplained occurrence of anoxic phosphorus (P) accumulation has largely hampered modeling of nitrification denitrification biological excess P removal (NDBEPR) systems. The aim of this study was, therefore, to isolate and identify denitrifying - P accumulating heterotrophic bacteria (DPBs) from a NDBEPR system in order to evaluate anoxic P accumulation and the specific mechanisms involved. Results of the study showed various heterotrophic bacteria to be capable of anoxic P accumulation utilising nitrate (NO3) as electron acceptor. While Pseudomonas spp. predominated, Serratia spp. and Vibrio spp. demonstrated the most efficient anoxic P accumulation with 7.10 and 7.29 mgPO4-P/L removal, respectively, at an initial NO3 concentration of 13.54 mgNO3-N/L and P concentration of 16.34 mgPO4-P/L. Weaker DPBs were also identified which were only capable of accumulating small amounts of P at low initial P and NO3 concentrations due to weak denitrification capacity. Anoxic P release was also observed due to the presence of acetate.
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4

Flatau, G. N., and M. J. Gauthier. "Cadmium accumulation by marine bacteria." Marine Environmental Research 17, no. 2-4 (January 1985): 159–62. http://dx.doi.org/10.1016/0141-1136(85)90070-4.

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5

Irawati, Wahyu. "ISOLASI DAN KARAKTERISASI BAKTERI RESISTEN TEMBAGA DARI PANTAI TIMUR SURABAYA." BIOLINK (Jurnal Biologi Lingkungan Industri Kesehatan) 6, no. 2 (December 17, 2019): 95–105. http://dx.doi.org/10.31289/biolink.v6i2.2558.

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Copper pollution in the East Coast of Surabaya is one of the serious cases of heavy metal pollution in Indonesia. Pollution at this location has been proven to result in fish deaths and brain damage of local residents because they consume too much copper-contaminated fish. Copper bioremediation using indigen bacteria isolated from polluted environments is a promising solution to overcome copper pollution problems. Bacteria that commonly live in polluted environments can be isolated and used as copper bioremediation agents. This study aims to do: 1) isolation and characterization of copper resistant bacteria from the East Coast of Surabaya, 2) resistance testing of bacterial isolates, and 3) copper accumulation and biosorbtion tests of bacterial isolates. The bacterial isolates were characterized by the morphology of the colonies and their cells based on Gram staining. Resistance testing is done by determining Minimum Inhibitory Concentration/MIC. The accumulation test is carried out by separating the cell and growth medium, then each of them is distructed using HNO3. The results of isolation and characterization obtained six isolates of copper-resistant bacteria, namely PmbC1, PmbC2, PmbC3, PmbC4, PmbC5, and PmbC6 with MIC = 3 mM - 5mM CuSO4. PmbC4 isolate is the most resistant bacteria with the MIC of 5 mM and is capable of accumulating copper of 6.25 mg per gram of cell dry weight and biosorbtion of 92.17%.
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6

Cama, Jehangir, Margaritis Voliotis, Jeremy Metz, Ashley Smith, Jari Iannucci, Ulrich F. Keyser, Krasimira Tsaneva-Atanasova, and Stefano Pagliara. "Single-cell microfluidics facilitates the rapid quantification of antibiotic accumulation in Gram-negative bacteria." Lab on a Chip 20, no. 15 (2020): 2765–75. http://dx.doi.org/10.1039/d0lc00242a.

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7

Günther, S., M. Trutnau, S. Kleinsteuber, G. Hause, T. Bley, I. Röske, H. Harms, and S. Müller. "Dynamics of Polyphosphate-Accumulating Bacteria in Wastewater Treatment Plant Microbial Communities Detected via DAPI (4′,6′-Diamidino-2-Phenylindole) and Tetracycline Labeling." Applied and Environmental Microbiology 75, no. 7 (January 30, 2009): 2111–21. http://dx.doi.org/10.1128/aem.01540-08.

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ABSTRACT Wastewater treatment plants with enhanced biological phosphorus removal represent a state-of-the-art technology. Nevertheless, the process of phosphate removal is prone to occasional failure. One reason is the lack of knowledge about the structure and function of the bacterial communities involved. Most of the bacteria are still not cultivable, and their functions during the wastewater treatment process are therefore unknown or subject of speculation. Here, flow cytometry was used to identify bacteria capable of polyphosphate accumulation within highly diverse communities. A novel fluorescent staining technique for the quantitative detection of polyphosphate granules on the cellular level was developed. It uses the bright green fluorescence of the antibiotic tetracycline when it complexes the divalent cations acting as a countercharge in polyphosphate granules. The dynamics of cellular DNA contents and cell sizes as growth indicators were determined in parallel to detect the most active polyphosphate-accumulating individuals/subcommunities and to determine their phylogenetic affiliation upon cell sorting. Phylotypes known as polyphosphate-accumulating organisms, such as a “Candidatus Accumulibacter”-like phylotype, were found, as well as members of the genera Pseudomonas and Tetrasphaera. The new method allows fast and convenient monitoring of the growth and polyphosphate accumulation dynamics of not-yet-cultivated bacteria in wastewater bacterial communities.
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8

Labry, C., D. Delmas, B. Moriceau, M. Gallinari, J. Quere, and A. Youenou. "Effect of P depletion on the functional pools of diatom carbohydrates, and their utilization by bacterial communities." Marine Ecology Progress Series 641 (May 7, 2020): 49–62. http://dx.doi.org/10.3354/meps13297.

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Phosphorus (P) limitation of phytoplankton growth is known to affect the accumulation and release of carbohydrates (CHO) by micro-algae. However, relatively little is known about the fate of algal exudates, notably their bacterial degradation. The CHO chemical characterization is also not exhaustive, especially in ‘functional’ pools relevant for phytoplankton physiology (particulate reserve [R] or structural [S] CHO) and for bacterial degradation (dissolved mono- [MDCHO] and polysaccharides [P-DCHO]). In this study, we investigated how P depletion and repletion affect the CHO composition in diatom Thalassiosira weissflogii cultures, and the shortterm response of free and diatom-attached bacteria in terms of abundance and potential βglucosidase activity (βGlc). The bacterial inoculum was composed of the bacterial consortiums of diatom precultures and a natural bacterial community from the Bay of Brest. P depletion favored CHO accumulation in diatom cells, mainly as R i.e. soluble CHO accumulated in cytoplasm, but also as S, polysaccharides linked to the cell wall. The R:S ratio was high in the present diatom cultures. The high M-DCHO observed in P-deplete cultures (twice that of P-replete cultures) when P-DCHO remained quite similar is explained both by active polysaccharide hydrolysis (very high potential βGlc of attached bacteria) and reduced uptake of M-DCHO by Pdepleted bacteria. P depletion of heterotrophic bacteria favors labile CHO accumulation, which may affect particle potential aggregation. However, the remarkably constant M-DCHO concentration over time for both conditions suggests tight coupling between phytoplankton accumulation, release, polymer hydrolysis and monomer uptake by bacteria.
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9

Correa-Galeote, David, Lucia Argiz, Angeles Val del Rio, Anuska Mosquera-Corral, Belen Juarez-Jimenez, Jesus Gonzalez-Lopez, and Belen Rodelas. "Dynamics of PHA-Accumulating Bacterial Communities Fed with Lipid-Rich Liquid Effluents from Fish-Canning Industries." Polymers 14, no. 7 (March 29, 2022): 1396. http://dx.doi.org/10.3390/polym14071396.

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The biosynthesis of polyhydroxyalkanoates (PHAs) from industrial wastes by mixed microbial cultures (MMCs) enriched in PHA-accumulating bacteria is a promising technology to replace petroleum-based plastics. However, the populations’ dynamics in the PHA-accumulating MMCs are not well known. Therefore, the main objective of this study was to address the shifts in the size and structure of the bacterial communities in two lab-scale sequencing batch reactors (SBRs) fed with fish-canning effluents and operated under non-saline (SBR-N, 0.5 g NaCl/L) or saline (SBR-S, 10 g NaCl/L) conditions, by using a combination of quantitative PCR and Illumina sequencing of bacterial 16S rRNA genes. A double growth limitation (DGL) strategy, in which nitrogen availability was limited and uncoupled to carbon addition, strongly modulated the relative abundances of the PHA-accumulating bacteria, leading to an increase in the accumulation of PHAs, independently of the saline conditions (average 9.04 wt% and 11.69 wt%, maximum yields 22.03 wt% and 26.33% SBR-N and SBR-S, respectively). On the other hand, no correlations were found among the PHAs accumulation yields and the absolute abundances of total Bacteria, which decreased through time in the SBR-N and did not present statistical differences in the SBR-S. Acinetobacter, Calothrix, Dyella, Flavobacterium, Novosphingobium, Qipengyuania, and Tsukamurella were key PHA-accumulating genera in both SBRs under the DGL strategy, which was revealed as a successful tool to obtain a PHA-enriched MMC using fish-canning effluents.
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10

Belliveau, B. H., M. E. Starodub, C. Cotter, and J. T. Trevors. "Metal resistance and accumulation in bacteria." Biotechnology Advances 5, no. 1 (January 1987): 101–27. http://dx.doi.org/10.1016/0734-9750(87)90006-1.

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11

Trevors, J. T. "Silver resistance and accumulation in bacteria." Enzyme and Microbial Technology 9, no. 6 (June 1987): 331–33. http://dx.doi.org/10.1016/0141-0229(87)90054-8.

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12

Morii, Yukako, Fumihiko Hasumi, and Tomoya Kitazume. "Accumulation of 2,2-difluoroethanol by bacteria." Journal of Fluorine Chemistry 125, no. 5 (May 2004): 731–33. http://dx.doi.org/10.1016/j.jfluchem.2003.12.009.

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13

Wang, Yifan, Huiqin Yao, Yan Zu, and Wenyan Yin. "Biodegradable MoOx@MB incorporated hydrogel as light-activated dressing for rapid and safe bacteria eradication and wound healing." RSC Advances 12, no. 15 (2022): 8862–77. http://dx.doi.org/10.1039/d2ra00963c.

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A photoactivated MoOx@MB-hy hydrogel was constructed with synergistic photothermal–photodynamic therapy properties for enhanced ROS accumulation on a bacterial surface to rapidly eradicate bacteria and accelerate the healing of wounds infected by drug-resistant bacteria.
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14

IRAWATI, WAHYU, TRIWIBOWO YUWONO, and NOMMENSEN PANGIHUTAN OMPUSUNGGU. "Growth characteristics and copper accumulation of bacterial consortium Acinetobacter sp. and Cupriavidus sp. isolated from a wastewater treatment plant." Biodiversitas Journal of Biological Diversity 19, no. 5 (September 21, 2018): 1884–90. http://dx.doi.org/10.13057/biodiv/d190541.

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Irawati W, Yuwono T, Ompusunggu NP. 2018. Growth characteristics and copper accumulation of bacterial consortium Acinetobacter sp. and Cupriavidus sp. isolated from a wastewater treatment plant. Biodiversitas 19: 1884-1890. Pollutant treatments are part of the human calling, as the crown of creation, to subdue, preserve, and cultivate the earth in bringing goodness for all creatures. Bioremediation of copper using indigenous bacteria is well known as the best water treatment for polluted environment recovery. Acinetobacter sp. and Cupriavidus sp. are indigenous bacteria isolated from industrial sewage in Indonesia. Bioremediation in environment is a process involving community of bacterial consortium for heavy metal or any other polluting materials accumulation. The purposes of this research were: (i) to characterize growth of Acinetobacter sp. and Cupriavidus sp. consortia in sewage medium, enrichment medium, and medium supplemented with copper, (ii) to establish the potency of bacterial consortia to accumulate copper. The growth of bacteria was observed based on cell turbidity using spectrophotometer at wavelength of 600 nm. Cells pellet was destructed by nitric acid at 100oC and copper concentration was analyzed by atomic absorption spectrophotometer as copper accumulation value. The results showed that the growth of bacterial consortia in medium containing copper was better than that of single bacterium. The best bacterial consortium was the mixture of Acinetobacter sp. IrC1 and Acinetobacter sp. IrC2. The use of sewage as cultivation medium decreased bacterial growth by up to 25% but still resulted in the same level of logarithmic phase in enrichment medium. The highest accumulation capability was of a consortium of Acinetobacter sp. IrC1 and Acinetobacter sp. IrC2 at a level of 6.45 g/mg copper/g cells dry weight, suggesting that 5.09% of copper were accumulated by cells. It was concluded that the best composition of consortia in growth and copper accumulation capability was the mixture of Acinetobacter sp. IrC1 and Acinetobacter sp. IrC2. These results may be due to the fact that both bacteria belong to the same genus that allowed them for synergistic interactions.
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15

Mayeed, M. S., A. Mian, G. W. Auner, and G. M. Newaz. "Accumulation of E. Coli Bacteria in Mini-Channel Flow." Journal of Biomechanical Engineering 128, no. 3 (November 18, 2005): 458–61. http://dx.doi.org/10.1115/1.2187049.

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The objective of this research is to design and optimize a mini/micro-channel based surface-accumulator of E. coli bacteria to be detected by acoustic wave biosensors. A computational approach has been carried out using the state of the art software, CFD-ACE with water as bacteria bearing fluid. E. coli bacteria have been modeled as random discrete particles tracked by solving the Lagrangian equations. The design challenges are to achieve low shear force (pico-N), high concentration at accumulation, and high enough Reynolds number to avoid bacteria swimming. A range of low Reynolds number (Re) has been considered along with the effects of particle boundary interactions, gravity, Saffman lift, etc. More than two orders of magnitude higher concentration at the accumulation than the inlet concentration, and lower shear force of less than pico-N have been achieved in the optimized designs.
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16

Mas-Castellà, J., and R. Guerrero. "Poly(β-hydroxyalkanoate) accumulation in bacterioplankton from Lake Cisó (Spain)." Canadian Journal of Microbiology 41, no. 13 (December 15, 1995): 80–83. http://dx.doi.org/10.1139/m95-173.

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The specific poly(β-hydroxyalkanoate) (PHA) content of the bacterioplankton from Lake Cisó (Spain) was measured at different depths. Phototrophic bacteria reach large populations in this lake and the PHA concentration changed seasonally according to their biomass. During summer stratification of the lake, phototrophic bacteria formed a metalimnetic peak. Bacterial counts were maximal at a depth of 1.5–2.0 m, whereas the PHA specific content reached a maximal value at 3.0–3.5 m. Since the limiting factor in this ecosystem is light availability, we assume that cells beneath the dense metalimnetic peak have unbalanced growth conditions and thus accumulate large amounts of PHA.Key words: bacterioplankton, PHA accumulation, Lake Cisó, light limitation.
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17

Wawrzyńska, Anna, Adam Wawrzyński, Dali Gaganidze, Edyta Kopera, Katarzyna Piatek, Wojciech Bal, and Agnieszka Sirko. "Overexpression of genes involved in phytochelatin biosynthesis in Escherichia coli: effects on growth, cadmium accumulation and thiol level." Acta Biochimica Polonica 52, no. 1 (March 31, 2005): 109–16. http://dx.doi.org/10.18388/abp.2005_3494.

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In Escherichia coli, heterologous production of Schizosaccharomyces pombe phytochelatin synthase (PCS) along with overproduction of E. coli serine acetyltransferase (SAT) and gamma-glutamylcysteine synthase (gammaECS) was achieved and resulted in the accumulation of phytochelatins in bacterial cells. Overproduction of either gammaECS alone or simultaneous production of all three proteins in bacterial cells were accompanied by reduced growth rate in liquid cultures. Interestingly, bacteria overproducing either gammaECS or both SAT and gammaECS (with elevated level of gamma-glutamylcysteine but not of phytochelatins) were able to accumulate more cadmium per dry weight than the control. However, the most efficient cadmium accumulation was observed in bacteria with elevated levels of all three proteins: SAT, gammaECS and PCS. Therefore, "pushing" the entire pathway might be the most promising approach in modification of bacteria for potential bioremediation purposes because the level of intermediates, cysteine and glutathione, can limit the rate of production of phytochelatins. However, in such bacteria other metabolic process might become limiting for efficient growth.
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18

HONMA, Hisahide, Masataka NAKATA, and Mamiko SAKINAGA. "Accumulation of Gold by Bacteria (Preliminary Report)." Journal of the Mineralogical Society of Japan 26, no. 2 (1996): 51–54. http://dx.doi.org/10.2465/gkk1952.26.51.

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19

Poolman, Bert, and Erwin Glaasker. "Regulation of compatible solute accumulation in bacteria." Molecular Microbiology 29, no. 2 (July 1998): 397–407. http://dx.doi.org/10.1046/j.1365-2958.1998.00875.x.

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20

Rodtong, Sureelak, Supavadee Songsrirote, Chantima Deeprasertkul, Nitinat Suppakarn, and Manote Sutheerawattananonda. "Accumulation of polyhydroxyalkanoates by starch-utilizing bacteria." Journal of Biotechnology 136 (October 2008): S447. http://dx.doi.org/10.1016/j.jbiotec.2008.07.1037.

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21

Van Milgen, Jaap, Larry L. Berger, and Michael R. Murphy. "An integrated, dynamic model of feed hydration anddigestion, and subsequent bacterial mass accumulation in the rumen." British Journal of Nutrition 70, no. 2 (September 1993): 471–83. http://dx.doi.org/10.1079/bjn19930141.

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Hydration of feeds and bacterial attachment to feed particles are thought to play major roles in rumen digestion of fibrous feedstuffs. The objective of the present study was to integrate these phenomena in a mechanistic model that could be used for data analysis. The proposed model was based on the conversion of biomass, where digestion end-products can be used for the synthesis of bacterial mass. Digestion of the potentially digestible fraction and subsequent accumulation of bacterial mass was based on a sequential, three-compartment model. These compartments represented substrate undergoing hydration, digestion, and bacterial mass accumulation. A fraction of the substrate was used for synthesis of bacterial mass. It was assumed that these bacteria associate either temporarily or permanently with the remaining substrate. Dacron bags containing either dry or fully-hydrated lucerne (Medicago sativa), maize (Zea mays) cobs, orchard grass (Dactylis glomeratd), and wheat straw were incubated in the rumen of a steer that was infused continuously with (15NH4)2SO4. The15N-enrichments of isolated particle-associated bacteria and residue remaining in the bags were used to estimate bacterial attachment. Substrate remaining and microbial mass accumulation were analysed simultaneously. Hydration did not appear to limit digestion. Fractional rate of digestion and appearance of attached bacterial mass was fastest for lucerne. For lucerne, 5 % of the digestion end-products were used for synthesis of bacteria that associated with the substrate, whereas for maize cobs, orchard grass, and wheat straw this was 16, 14, and 19% respectively. Less than 2% of digestion end-products were used for synthesis of bacteria that permanently remained associated with the substrate. Permanent association can occur only with the indigestible fraction, and probably represents bacterial debris. Lysis and/or detachment of bacterial cells was highest for lucerne, and was indicative of the rapid dynamics of lucerne digestion.
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22

Gibson, Beth, and Adam Eyre-Walker. "Investigating Evolutionary Rate Variation in Bacteria." Journal of Molecular Evolution 87, no. 9-10 (September 30, 2019): 317–26. http://dx.doi.org/10.1007/s00239-019-09912-5.

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Abstract Rates of molecular evolution are known to vary between species and across all kingdoms of life. Here, we explore variation in the rate at which bacteria accumulate mutations (accumulation rates) in their natural environments over short periods of time. We have compiled estimates of the accumulation rate for over 34 species of bacteria, the majority of which are pathogens evolving either within an individual host or during outbreaks. Across species, we find that accumulation rates vary by over 3700-fold. We investigate whether accumulation rates are associated to a number potential correlates including genome size, GC content, measures of the natural selection and the time frame over which the accumulation rates were estimated. After controlling for phylogenetic non-independence, we find that the accumulation rate is not significantly correlated to any factor. Furthermore, contrary to previous results, we find that it is not impacted by the time frame of which the estimate was made. However, our study, with only 34 species, is likely to lack power to detect anything but large effects. We suggest that much of the rate variation may be explained by differences between species in the generation time in the wild.
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23

Durn, G., J. Hrenovic, and L. Sekovanic. "Terra rossa as the substrate for biological phosphate removal from wastewater." Clay Minerals 48, no. 5 (December 2013): 725–38. http://dx.doi.org/10.1180/claymin.2013.048.5.05.

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AbstractThree samples of terra rossa were shown to be efficient adsorbents of phosphate [P(V)] from wastewater and removed 29.9–32.6% of P(V). The total iron content in terra rossa was the key factor which determined the P(V) removal from wastewater. The original samples of terra rossa were effective support materials for the immobilization of metabolically active P(V)-accumulating bacteriaAcinetobacter junii(0.56–2.47×1010CFU g–1). The removal of oxalate-extractable iron from original sample of terra rossa increased the number of immobilized bacteria to 1.34×10–11CFU g–1, which is the largest number of immobilized bacteria reported in the literature so far. In reactors containing theA. juniiand terra rossa P(V) was removed from wastewater by simultaneous adsorption onto terra rossa and accumulation inside bacterial cells, resulting in 40.5–62.5% of P(V) removal. Terra rossa is a promising substrate for biological P(V) removal from wastewater, acting both as adsorbent of P(V) and carrier of P(V)-accumulating bacteria.
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24

Denton, Bethany L., Leanne E. Diese, Jeffrey L. Firkins, and Timothy J. Hackmann. "Accumulation of Reserve Carbohydrate by Rumen Protozoa and Bacteria in Competition for Glucose." Applied and Environmental Microbiology 81, no. 5 (December 29, 2014): 1832–38. http://dx.doi.org/10.1128/aem.03736-14.

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ABSTRACTThe aim of this study was to determine if rumen protozoa could form large amounts of reserve carbohydrate compared to the amounts formed by bacteria when competing for glucose in batch cultures. We separated large protozoa and small bacteria from rumen fluid by filtration and centrifugation, recombined equal protein masses of each group into one mixture, and subsequently harvested (reseparated) these groups at intervals after glucose dosing. This method allowed us to monitor reserve carbohydrate accumulation of protozoa and bacteria individually. When mixtures were dosed with a moderate concentration of glucose (4.62 or 5 mM) (n= 2 each), protozoa accumulated large amounts of reserve carbohydrate; 58.7% (standard error of the mean [SEM], 2.2%) glucose carbon was recovered from protozoal reserve carbohydrate at time of peak reserve carbohydrate concentrations. Only 1.7% (SEM, 2.2%) was recovered in bacterial reserve carbohydrate, which was less than that for protozoa (P< 0.001). When provided a high concentration of glucose (20 mM) (n= 4 each), 24.1% (SEM, 2.2%) of glucose carbon was recovered from protozoal reserve carbohydrate, which was still higher (P= 0.001) than the 5.0% (SEM, 2.2%) glucose carbon recovered from bacterial reserve carbohydrate. Our novel competition experiments directly demonstrate that mixed protozoa can sequester sugar away from bacteria by accumulating reserve carbohydrate, giving protozoa a competitive advantage and stabilizing fermentation in the rumen. Similar experiments could be used to investigate the importance of starch sequestration.
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25

Finlay, B. B., S. Ruschkowski, and S. Dedhar. "Cytoskeletal rearrangements accompanying salmonella entry into epithelial cells." Journal of Cell Science 99, no. 2 (June 1, 1991): 283–96. http://dx.doi.org/10.1242/jcs.99.2.283.

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Salmonella bacteria can enter (invade) eukaryotic cells, and exist as intracellular parasites. Confocal, light immunofluorescence and electron microscopy were used to examine various cytoskeletal components of cultured Madin Darby canine kidney (MDCK) and HeLa epithelial cells after infection with Salmonella typhimurium. These bacteria entered and remained within membrane-bound vacuoles and were surrounded by large (5–10 microns) dense structures composed of various cytoskeletal components. These structures consisted of extensive aggregations of polymerized actin, alpha-actinin and tropomyosin above and beside the invading bacterium in both epithelial cell lines. These structures were evident soon after bacterial addition (maximal at 20 min for HeLa cells, 60 min for MDCK cells), and disappeared later in the infection as the cytoskeletal components returned to a more normal distribution after bacterial internalization. Surprisingly, tubulin also aggregated above internalized Salmonella although bacterial entry or penetration through polarized monolayers was not disrupted by the microtubule-inhibiting agent nocadazole (this treatment actually enhanced tubulin accumulation around these organisms). There were little if any rearrangements in intermediate filaments composed of keratin or vimentin. Large amounts of talin also accumulated above and around invading Salmonella, but there was only a minor accumulation of vinculin around a few organisms. Pretreatment of epithelial cells with the microfilament inhibitor cytochalasin D blocked bacterial internalization but did not prevent accumulation of polymerized actin and alpha-actinin directly beneath uninternalized bacteria, yet prevented accumulation of the other cytoskeletal components. These results suggest that Salmonella bind to the surface and trigger a signal in epithelial cells that causes marked rearrangements in various cytoskeletal components, including recruitment of actin filaments and alpha-actinin, which then generates the force necessary for bacterial uptake.
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Tanaka, Masayoshi, William Knowles, Rosemary Brown, Nicole Hondow, Atsushi Arakaki, Stephen Baldwin, Sarah Staniland, and Tadashi Matsunaga. "Biomagnetic Recovery and Bioaccumulation of Selenium Granules in Magnetotactic Bacteria." Applied and Environmental Microbiology 82, no. 13 (April 22, 2016): 3886–91. http://dx.doi.org/10.1128/aem.00508-16.

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ABSTRACTUsing microorganisms to remove waste and/or neutralize pollutants from contaminated water is attracting much attention due to the environmentally friendly nature of this methodology. However, cell recovery remains a bottleneck and a considerable challenge for the development of this process. Magnetotactic bacteria are a unique group of organisms that can be manipulated by an external magnetic field due to the presence of biogenic magnetite crystals formed within their cells. In this study, we demonstrated an account of accumulation and precipitation of amorphous elemental selenium nanoparticles within magnetotactic bacteria alongside and independent of magnetite crystal biomineralization when grown in a medium containing selenium oxyanion (SeO32−). Quantitative analysis shows that magnetotactic bacteria accumulate the largest amount of target molecules (Se) per cell compared with any other previously reported nonferrous metal/metalloid. For example, 2.4 and 174 times more Se is accumulated than Te taken up into cells and Cd2+adsorbed onto the cell surface, respectively. Crucially, the bacteria with high levels of Se accumulation were successfully recovered with an external magnetic field. The biomagnetic recovery and the effective accumulation of target elements demonstrate the potential for application in bioremediation of polluted water.IMPORTANCEThe development of a technique for effective environmental water remediation is urgently required across the globe. A biological remediation process of waste removal and/or neutralization of pollutant from contaminated water using microorganisms has great potential, but cell recovery remains a bottleneck. Magnetotactic bacteria synthesize magnetic particles within their cells, which can be recovered by a magnetic field. Herein, we report an example of accumulation and precipitation of amorphous elemental selenium nanoparticles within magnetotactic bacteria independent of magnetic particle synthesis. The cells were able to accumulate the largest amount of Se compared to other foreign elements. More importantly, the Se-accumulating bacteria were successfully recovered with an external magnetic field. We believe magnetotactic bacteria confer unique advantages of biomagnetic cell recovery and of Se accumulation, providing a new and effective methodology for bioremediation of polluted water.
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Gorobets, Svitlana, Oksana Gorobets, and Svitlana Kovalova. "Bioinformatic Analysis of the Genetic Mechanism of Biomineralization of Biogenic Magnetic Nanoparticles in Bacteria Capable of Tumor-Specific Accumulation." Innovative Biosystems and Bioengineering 6, no. 2 (September 5, 2022): 48–55. http://dx.doi.org/10.20535/ibb.2022.6.2.260183.

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Background. Current methods of targeted cancer therapy are not always effective enough and can lead to side effects, such as an increased risk of autoimmune diseases. It is known that some bacteria are capable of specific accumulation in malignant tumors, and therefore can be used as an alternative means of targeted drug delivery. However, the genetic mechanism of tumor-specific accumulation of bacteria is not fully understood and needs to be studied in more detail. Objective. This work aims to identify, by methods of comparative genomics methods, magnetically controlled bacteria among those for which tumor-specific accumulation has already been experimentally shown. Methods. To identify magnetically controlled bacterial strains, i.e., bacteria that biomineralize biogenic magnetic nanoparticles (BMN), the method of comparative genomics was used, namely: pairwise alignment of proteomes with amino acid sequences of Mam-proteins of required for biomineralization of BMN in magneto­tactic bacteria Magnetospirillum gryphiswaldense MSR-1. Sequence alignments were performed in the BLAST program of the US National Center for Biotechnology Information (NCBI). Results. The conducted bioinformatic analysis showed that strains of bacteria in which the ability to accumulate specifically in tumors has been experimentally proven are potential producers of BMN of different types. Among them there are potential producers of intracellular crystalline BMN, potential producers of intracellular amorphous BMN, and extracellular crystalline BMN Conclusions. It is expedient to use bacteria-producing BMN as gene vectors and systems of targeted drug delivery to tumors that biomineralize BMN.
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Kunte, Hans Jörg. "Osmoregulation in Bacteria: Compatible Solute Accumulation and Osmosensing." Environmental Chemistry 3, no. 2 (2006): 94. http://dx.doi.org/10.1071/en06016.

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Environmental Context.Bacteria and Archaea have developed two basic mechanisms to cope with osmotic stress. The ‘salt-in-cytoplasm mechanism’ involves adjusting the salt concentration in the cytoplasm according to the environmental osmolarity and the ‘organic-osmolyte mechanism’ involves accumulating uncharged, highly water-soluble organic compounds in order to maintain an osmotic equilibrium with the surrounding medium. This highlight gives an overview of the osmoadaptation of prokaryotes employing the organic-osmolyte strategy and introduces a model explaining the fine-tuning of osmoregulatory osmolyte synthesis. Abstract.Bacteria and Archaea have developed two basic mechanisms to cope with osmotic stress, the salt-in-cytoplasm mechanism, and the organic-osmolyte mechanism. Organic osmolytes or so-called compatible solutes can be accumulated in molar concentration in the cytoplasm and allow for the adaptation of bacterial cells to varying salt concentrations. The biosynthetic pathways of compatible solutes and different compatible solute transport systems are described. A model for osmoregulatory compatible solute accumulation is introduced.
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Millar, Jess A., and Rahul Raghavan. "Accumulation and expression of multiple antibiotic resistance genes in Arcobacter cryaerophilus that thrives in sewage." PeerJ 5 (April 25, 2017): e3269. http://dx.doi.org/10.7717/peerj.3269.

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We explored the bacterial diversity of untreated sewage influent samples of a wastewater treatment plant in Tucson, AZ and discovered that Arcobacter cryaerophilus, an emerging human pathogen of animal origin, was the most dominant bacterium. The other highly prevalent bacteria were members of the phyla Bacteroidetes and Firmicutes, which are major constituents of human gut microbiome, indicating that bacteria of human and animal origin intermingle in sewage. By assembling a near-complete genome of A. cryaerophilus, we show that the bacterium has accumulated a large number of antibiotic resistance genes (ARGs) probably enabling it to thrive in the wastewater. We also determined that a majority of ARGs was being expressed in sewage, suggestive of trace levels of antibiotics or other stresses that could act as a selective force that amplifies multidrug resistant bacteria in municipal sewage. Because all bacteria are not eliminated even after several rounds of wastewater treatment, ARGs in sewage could affect public health due to their potential to contaminate environmental water.
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Wood, Janet M., Erhard Bremer, Laszlo N. Csonka, Reinhard Kraemer, Bert Poolman, Tiemen van der Heide, and Linda T. Smith. "Osmosensing and osmoregulatory compatible solute accumulation by bacteria." Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology 130, no. 3 (October 2001): 437–60. http://dx.doi.org/10.1016/s1095-6433(01)00442-1.

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31

Gadd, G. M. "Heavy metal accumulation by bacteria and other microorganisms." Experientia 46, no. 8 (August 1990): 834–40. http://dx.doi.org/10.1007/bf01935534.

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32

Jørgensen, Kirsten S., and Anneli S. L. Pauli. "Polyphosphate Accumulation among Denitrifying Bacteria in Activated Sludge." Anaerobe 1, no. 3 (June 1995): 161–68. http://dx.doi.org/10.1006/anae.1995.1014.

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33

KIM, SHIN-HEE, KATHARINE G. FIELD, DONG-SUCK CHANG, CHENG-I. WEI, and HAEJUNG AN. "Identification of Bacteria Crucial to Histamine Accumulation in Pacific Mackerel during Storage†." Journal of Food Protection 64, no. 10 (October 1, 2001): 1556–64. http://dx.doi.org/10.4315/0362-028x-64.10.1556.

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Bacterial growth and histamine formation in Pacific mackerel during storage at 0, 4, 15, and 25°C were monitored. To identify bacterial species contributing to histamine formation, several groups of bacteria were isolated by using selective media under temperatures corresponding to the various storage conditions. Initially, low counts of bacteria were found in the gill, skin, and intestine of fresh fish, and only weak histamine formers were found in the gill. Histamine was found in the muscle when fish were stored above 4°C, and aerobic plate counts reached 106 CFU/g. When fish became unsuitable for human consumption by abusive storage, toxicological levels of histamine were always found. The highest level of histamine formed was 283 mg/100 g in 2 days. The optimum temperature for supporting growth of prolific histamine formers was 25°C. The most prolific and prevalent histamine former was Morganella morganii, followed by Proteus vulgaris, both of which were isolated on violet red bile glucose (VRBG) agar. At 15°C, a significant level of histamine was still produced in fish muscle, although prolific histamine formers were less frequently detected than at 25°C. The isolates on thiosulfate citrate bile salts sucrose (TCBS) agar were weak histamine formers and identified as Vibrio parahaemolyticus and Vibrio alginolyticus. At 4°C, less than 57.4 mg/100 g of histamine was found in fish stored for 14 days. Most isolates were natural bacterial flora in the marine environment and identified as weak histamine formers. At 0°C, neither histamine former nor histamine production was detected up to 14 days of storage.
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Carpa, Rahela, Anca Butiuc-Keul, Iulia Lupan, Lucian Barbu-Tudoran, Vasile Muntean, and Cristina Dobrotă. "Poly-β-hydroxybutyrate accumulation in bacterial consortia from different environments." Canadian Journal of Microbiology 58, no. 5 (May 2012): 660–67. http://dx.doi.org/10.1139/w2012-037.

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The aim of the present study was to examine soil samples from various vegetation zones in terms of physicochemical properties, microbial communities, and isolation and identification (by polymerase chain reaction and transmission electron microscopy) of bacteria producing poly-β-hydroxybutyrates (PHBs). Soil samples were analysed originating from zones with heterogeneous environmental conditions from the Romanian Carpathian Mountains (mountain zone with alpine meadow, karstic zone with limestone meadow, hill zone with xerophilous meadow, and flood plain zone with hygrophilic meadow). Different bacterial groups involved in the nitrogen cycle (aerobic mesophilic heterotrophs, ammonifiers, denitrifiers, nitrifiers, and free nitrogen-fixing bacteria from Azotobacter genus) were analysed. Soil biological quality was assessed by the bacterial indicator of soil quality, which varied between 4.3 and 4.7. A colony polymerase chain reaction technique was used for screening PHB producers. With different primers, specific bands were obtained in all the soil samples. Some wild types of Azotobacter species were isolated from the 4 studied sites. Biodegradable polymers of PHB were assessed by negative staining in transmission electron microscopy. The maximum PHB granules density was obtained in the strains isolated from the xerophilous meadow (10–18 granules/cell), which was the most stressful environment from all the studied sites, as the physicochemical and microbiological tests proved.
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Furneri, Pio M., Massimo Fresta, Giovanni Puglisi, and Gianna Tempera. "Ofloxacin-Loaded Liposomes: In Vitro Activity and Drug Accumulation in Bacteria." Antimicrobial Agents and Chemotherapy 44, no. 9 (September 1, 2000): 2458–64. http://dx.doi.org/10.1128/aac.44.9.2458-2464.2000.

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ABSTRACT Different ofloxacin-loaded unilamellar vesicles were prepared by the extrusion technique, and their antimicrobial activities were determined in comparison to those of the free drug by means of MIC determinations with both American Type Culture Collection standards and wild-type bacterial strains (six strains of Enterococcus faecalis, seven strains of Escherichia coli, six strains of Staphylococcus aureus, and six strains ofPseudomonas aeruginosa). The accumulation of ofloxacin and liposome-ofloxacin was measured by determining the amount of the drug inside the bacteria as a function of time. Encapsulated fluoroquinolone yielded MICs which were at least twofold lower than those obtained with the free drug. In particular, liposomes made up of dimyristoylphosphatidylcholine-cholesterol-dipalmitoylphosphatidylserine and dimyristoylphosphatidylcholine-cholesterol-dihexadecylphosphate (4:3:4 molar ratio) provided the best improvement in antimicrobial activity against the various bacterial strains investigated. The liposome formulation produced higher intracellular fluoroquinolone concentrations than those achieved simultaneously with the free drug in both E. coli and P. aeruginosa.
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You, Chuan, Dan Qin, Yumeng Wang, Wenyi Lan, Yehong Li, Baohong Yu, Yajun Peng, Jieru Xu, and Jinyan Dong. "Plant Triterpenoids Regulate Endophyte Community to Promote Medicinal Plant Schisandra sphenanthera Growth and Metabolites Accumulation." Journal of Fungi 7, no. 10 (September 23, 2021): 788. http://dx.doi.org/10.3390/jof7100788.

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Beneficial interactions between endophytes and plants are critical for plant growth and metabolite accumulation. Nevertheless, the secondary metabolites controlling the feedback between the host plant and the endophytic microbial community remain elusive in medicinal plants. In this report, we demonstrate that plant-derived triterpenoids predominantly promote the growth of endophytic bacteria and fungi, which in turn promote host plant growth and secondary metabolite productions. From culturable bacterial and fungal microbial strains isolated from the medicinal plant Schisandra sphenanthera, through triterpenoid-mediated screens, we constructed six synthetic communities (SynComs). By using a binary interaction method in plates, we revealed that triterpenoid-promoted bacterial and fungal strains (TPB and TPF) played more positive roles in the microbial community. The functional screening of representative strains suggested that TPB and TPF provide more beneficial abilities to the host. Moreover, pot experiments in a sterilized system further demonstrated that TPB and TPF play important roles in host growth and metabolite accumulation. In summary, these experiments revealed a role of triterpenoids in endophytic microbiome assembly and indicated a strategy for constructing SynComs on the basis of the screening of secondary metabolites, in which bacteria and fungi join forces to promote plant health. These findings may open new avenues towards the breeding of high yielding and high metabolite-accumulating medicinal plants by exploiting their interaction with beneficial endophytes.
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Obruca, Stanislav, Leos Doskocil, Vladislav Krzyzanek, Kamila Hrubanova, Petr Sedlacek, Filip Mravec, Ota Samek, Dan Kucera, Pavla Benesova, and Ivana Marova. "Polyhydroxyalkanoates in Bacterial Cells - More Than just Storage Materials." Materials Science Forum 851 (April 2016): 20–25. http://dx.doi.org/10.4028/www.scientific.net/msf.851.20.

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Since polyhydroxyalkanoates (PHAs) belong among the most widespread storage materials within bacteria genus, it can be assumed that the ability of PHAs accumulation represent significant advantage in the natural environments. Of course, probably the most obvious is the possibility to utilize PHAs when external carbon sources are depleted. Nevertheless, it is likely that PHAs play much more complex role in the stress response of bacteria. Therefore, the aim of this work was to investigate possible influence of PHA accumulation in bacteria on physical properties of the cells and their cytoplasm with respect to possible stress survival. Cells of bacteria Cupriavidus necator H16 with various poly(3-hydroxybutyrate) (PHB) content (25 – 91 % of cell dry weight) were subjected to analytical centrifugation employing LUMiSizer. We observed that slope of index instability of bacterial culture increased with rise of PHB content in cells. It indicates that accumulation of PHB granules in bacterial cells affects overall physico-mechanical properties of the cells in particular sedimentation potential and density which might influence their behavior in natural environment such as sedimentation, surface absorption and subsequent biofilm formation. Furthermore, when investigated by Cryo-SEM, the PHB containing cells showed needle-type plastic deformations while these structures were absent in the cells without polymer. This suggests that native intracellular PHB granules reveal completely different mechanical and physico-chemical properties than any other component of bacterial cytoplasm and their flexibility even in deeply-frozen state is significantly higher than that of PHB isolated from bacterial cells. Based on these observations, it can be expected that, aside from their involvement in metabolism, presence of PHB granules dramatically changes physico-mechanical properties of cytoplasm and overall properties of cells which might represent important advantage when cells are exposed to stress conditions.
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Nwachukwu, Blessing Chidinma, Ayansina Segun Ayangbenro, and Olubukola Oluranti Babalola. "Elucidating the Rhizosphere Associated Bacteria for Environmental Sustainability." Agriculture 11, no. 1 (January 18, 2021): 75. http://dx.doi.org/10.3390/agriculture11010075.

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The abundance of nutrient accumulation in rhizosphere soils has placed the rhizosphere as an “epicenter” of bacterial concentrations. Nonetheless, over the years, little attention has been given to bacterial inoculants and soil-like substrates. The reason is that many farmers and experiments have focused on chemical fertilizers as an approach to improve plant growth and yield. Therefore, we focused on assessing the application of rhizosphere soil and its associated bacteria for biotechnological applications. This review has been structured into major subunits: rhizosphere soil as a treasure trove for bacterial community concentration, biodegradation of lignocellulose for biofuel production, rhizosphere soil and its bacteria as soil amendments, and the role of rhizosphere soil and its bacteria for bioremediation and biofiltration. Hence, the efficient use of rhizosphere soil and its bacteria in an environmentally friendly way can contribute to healthy and sustainable environments.
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39

Ji, Chunhui, Randy B. Stockbridge, and Christopher Miller. "Bacterial fluoride resistance, Fluc channels, and the weak acid accumulation effect." Journal of General Physiology 144, no. 3 (August 25, 2014): 257–61. http://dx.doi.org/10.1085/jgp.201411243.

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Fluoride ion (F−) is a ubiquitous environmental threat to microorganisms, which have evolved a family of highly selective “Fluc” F− channels that export this inhibitory anion from their cytoplasm. It is unclear, however, how a thermodynamically passive mechanism like an ion channel can protect against high concentrations of external F−. We monitored external F− concentrations in Escherichia coli suspensions and showed that, in bacteria lacking Fluc, F− accumulates when the external medium is acidified, as a predicted function of the transmembrane pH gradient. This weak acid accumulation effect, which results from the high pKa (3.4) and membrane permeability of HF, is abolished by Fluc channels. We also found that, although bacterial growth is inhibited by high concentrations of F−, bacteria can withstand cytoplasmic F− at levels a hundred times higher than those that inhibit proliferation, resuming growth when the F− challenge is removed.
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40

Li, Hsiu-Ping, Robin Brinkmeyer, Whitney L. Jones, Saijin Zhang, Chen Xu, Kathy A. Schwehr, Peter H. Santschi, Daniel I. Kaplan, and Chris M. Yeager. "Iodide Accumulation by Aerobic Bacteria Isolated from Subsurface Sediments of a129I-Contaminated Aquifer at the Savannah River Site, South Carolina." Applied and Environmental Microbiology 77, no. 6 (January 28, 2011): 2153–60. http://dx.doi.org/10.1128/aem.02164-10.

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ABSTRACT129I is of major concern because of its mobility in the environment, excessive inventory, toxicity (it accumulates in the thyroid), and long half-life (∼16 million years). The aim of this study was to determine if bacteria from a129I-contaminated oxic aquifer at the F area of the U.S. Department of Energy's Savannah River Site, SC, could accumulate iodide at environmentally relevant concentrations (0.1 μM I−). Iodide accumulation capability was found in 3 out of 136 aerobic bacterial strains isolated from the F area that were closely related toStreptomyces/Kitasatosporaspp.,Bacillus mycoides, andRalstonia/Cupriavidusspp. Two previously described iodide-accumulating marine strains, aFlexibacter aggregansstrain and anArenibacter troitsensisstrain, accumulated 2 to 50% total iodide (0.1 μM), whereas the F-area strains accumulated just 0.2 to 2.0%. Iodide accumulation by FA-30 was stimulated by the addition of H2O2, was not inhibited by chloride ions (27 mM), did not exhibit substrate saturation kinetics with regard to I−concentration (up to 10 μM I−), and increased at pH values of <6. Overall, the data indicate that I−accumulation likely results from electrophilic substitution of cellular organic molecules. This study demonstrates that readily culturable, aerobic bacteria of the F-area aquifer do not accumulate significant amounts of iodide; however, this mechanism may contribute to the long-term fate and transport of129I and to the biogeochemical cycling of iodine over geologic time.
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41

Masaaki Minami, Shin-nosuke Hashikawa, Takafumi Ando, Hidemi Goto, and Michio Ohta. "AcrB is essential for bile acid tolerance in Helicobacter pylori." GSC Advanced Research and Reviews 10, no. 2 (February 28, 2022): 099–106. http://dx.doi.org/10.30574/gscarr.2022.10.2.0055.

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Resistance to bile acids is a necessary ability for bacteria that live in the gastrointestinal tract, such as Helicobacter pylori. The role of the bacterial drug efflux system is important for bile acid tolerance. Using the H. pylori JP26 strain and the JP26AcrB strain deficient in AcrB the relationship between the drug efflux system AcrB and the bile acid tolerance of H. pylori was investigated. Bacterial susceptibility to bile acids was measured by the agar dilution method. To examine the ability to efflux bile acids, the intracellular accumulation of radiolabeled chenodeoxycholic acid was measured with a liquid scintillation counter. To investigate the effect of bile acid on the cell adhesion ability of bacteria, bacteria were attached to AGS cells supplemented with chenodeoxycholic acid, and the number of bacteria was counted. Bile acid resistance was significantly lower in the AcrB mutant than in the wild-type strain. The AcrB mutant strains showed a significant increase in the accumulation of 14C - labeled chenodeoxycholic acid in the bacteria. In terms of attachment to AGS cells, the AcrB mutant was significantly lower than the wild-type strain. Furthermore, the AcrB mutant with chenodeoxycholic acid could not be identified. Our results reveal that H. pylori AcrB plays an important role in bile acid resistance. We also suggest that drugs targeting the AcrB efflux system may be a new treatment for H. pylori.
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42

Gouveia, Joao D., Jie Lian, Georg Steinert, Hauke Smidt, Detmer Sipkema, Rene H. Wijffels, and Maria J. Barbosa. "Associated bacteria of Botryococcus braunii (Chlorophyta)." PeerJ 7 (March 27, 2019): e6610. http://dx.doi.org/10.7717/peerj.6610.

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Botryococcus braunii (Chlorophyta) is a green microalga known for producing hydrocarbons and exopolysaccharides (EPS). Improving the biomass productivity of B. braunii and hence, the productivity of the hydrocarbons and of the EPS, will make B. braunii more attractive for industries. Microalgae usually cohabit with bacteria which leads to the formation of species-specific communities with environmental and biological advantages. Bacteria have been found and identified with a few B. braunii strains, but little is known about the bacterial community across the different strains. A better knowledge of the bacterial community of B. braunii will help to optimize the biomass productivity, hydrocarbons, and EPS accumulation. To better understand the bacterial community diversity of B. braunii, we screened 12 strains from culture collections. Using 16S rRNA gene analysis by MiSeq we described the bacterial diversity across 12 B. braunii strains and identified possible shared communities. We found three bacterial families common to all strains: Rhizobiaceae, Bradyrhizobiaceae, and Comamonadaceae. Additionally, the results also suggest that each strain has its own specific bacteria that may be the result of long-term isolated culture.
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43

Okada, M., A. Murakami, C. K. Lin, Y. Ueno, and T. Okubo. "Population Dynamics of Bacteria for Phosphorus Removal in Sequencing Batch Reactor (SBR) Activated Sludge Processes." Water Science and Technology 23, no. 4-6 (February 1, 1991): 755–63. http://dx.doi.org/10.2166/wst.1991.0526.

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Laboratory-scale sequencing batch reactor (SBR) activated sludge processes were operated using synthetic wastewater to clarify the effects of sludge retention time(SRT) and organic substrates on the accumulation of bio-P-bacteria. The accumulation of bio-P-bacteria could be enhanced by wide variation in concentration of organic substrates by giving a short fill period and sufficient anaerobic conditions. However, the accumulation could not be enhanced in the reactor operated with SRT less than 25 d in spite of the higher, more than 0.1 d−1, specific growth rates observed in the isolated strains of bio-P-bacteria. The specific growth rates of bio-P-bacteria were estimated at 0.040 d−1, 0.030 d−1 and 0.035 d−1 in the SBR activated sludge processes fed with sodium acetate (A), glucose and polypeptone (GP) and polypeptone (P), respectively. Therefore, a large sludge retention time would be necessary for the accumulation of bio-P-bacteria. Volatile fatty acids (VFA), such as sodium acetate (A), seemed to be more effective than other organic substrates (GP and P) for the accumulation of bio-P-bacteria in activated sludge ecosystems.
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44

Park, Jun-Gyu, Won-Beom Shin, Wei-Qi Shi, and Hang-Bae Jun. "Changes of Bacterial Communities in an Anaerobic Digestion and a Bio-Electrochemical Anaerobic Digestion Reactors According to Organic Load." Energies 12, no. 15 (August 1, 2019): 2958. http://dx.doi.org/10.3390/en12152958.

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Bacterial communities change in bulk solution of anaerobic digestion (AD) and bio-electrochemical anaerobic digestion reactors (BEAD) were monitored at each organic loading rate (OLR) to investigate the effect of voltage supply on bacterial species change in bulk solution. Chemical oxygen demand (COD) degradation and methane production from AD and BEAD reactors were also analyzed by gradually increasing food waste OLR. The BEAD reactor maintained stable COD removal and methane production at 6.0 kg/m3·d. The maximum OLR of AD reactor for optimal operation was 4.0 kg/m3·d. pH and alkalinity decline and volatile fatty acid (VFA) accumulation, which are the problem in high load anaerobic digestion of readily decomposable food wastes, were again the major factors destroying the optimal operation condition of the AD reactor at 6.0 kg/m3·d. Contrarily, the electrochemically activated dense communities of exoelectrogenic bacteria and VFA-oxidizing bacteria prevented VFAs from accumulating inside the BEAD reactor. This maintained stable pH and alkalinity conditions, ultimately contributing to stable methane production.
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45

Pogue, Amy J., and Kimberley A. Gilbride. "Impact of protozoan grazing on nitrification and the ammonia- and nitrite-oxidizing bacterial communities in activated sludge." Canadian Journal of Microbiology 53, no. 5 (May 2007): 559–71. http://dx.doi.org/10.1139/w07-027.

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In activated sludge, protozoa feed on free-swimming bacteria and suspended particles, inducing flocculation and increasing the turnover rate of nutrients. In this study, the effect of protozoan grazing on nitrification rates under various conditions in municipal activated sludge batch reactors was examined, as was the spatial distribution of ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) within the activated sludge. The reactors were monitored for ammonia, nitrite, nitrate, and total nitrogen concentrations, and bacterial numbers in the presence and absence of cycloheximide (a protozoan inhibitor), allylthiourea (an inhibitor of ammonia oxidation), and EDTA (a deflocculating agent). The accumulations of nitrate, nitrite, and ammonia were lower in batches without than with protozoa grazing. Inhibition of ammonia oxidation also decreased the amount of nitrite and nitrate accumulation. Inhibiting protozoan grazing along with ammonia oxidation further decreased the amounts of nitrite and nitrate accumulated. Induction of deflocculation led to high nitrate accumulation, indicating high levels of nitrification; this effect was lessened in the absence of protozoan grazing. Using fluorescent in situ hybridization and confocal laser scanning microscopy, AOB and NOB were found clustered within the floc, and inhibiting the protozoa, inhibiting ammonia oxidation, or inducing flocculation did not appear to lower the number of AOB and NOB present or affect their position within the floc. These results suggest that the AOB and NOB are present but less active in the absence of protozoa.
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46

Tets, Victor V., G. V. Tets, and K. M. Kardava. "Distribution of bacterial spores in supermarkets." Hygiene and sanitation 96, no. 2 (March 27, 2019): 124–27. http://dx.doi.org/10.18821/0016-9900-2017-96-2-124-127.

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This work presents results of the study on the environment prevalence of spores of aerobic bacteria, which are of potential danger to human health. The investigation of swabs from handles of supermarket trolleys revealed on their surface the presence of a large number of spores of unrelated pathogenic bacteria carrying as antibiotic resistance genes and the origin of genes protected by bacterial spores from harmful environmental conditions as well. The high resistance of bacterial spores to antiseptics and disinfectants can be considered as the reason for the their accumulation in the environment.
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47

Arce-Inga, Marielita, Alex Ricardo González-Pérez, Elgar Hernandez-Diaz, Beimer Chuquibala-Checan, Antony Chavez-Jalk, Kelvin James Llanos-Gomez, Santos Triunfo Leiva-Espinoza, Segundo Manuel Oliva-Cruz, and Liz Marjory Cumpa-Velasquez. "Bioremediation Potential of Native Bacillus sp. Strains as a Sustainable Strategy for Cadmium Accumulation of Theobroma cacao in Amazonas Region." Microorganisms 10, no. 11 (October 25, 2022): 2108. http://dx.doi.org/10.3390/microorganisms10112108.

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Cacao plant cadmium accumulation has become a major concern, especially for small Amazonian producers. A sustainable alternative to address its toxicity is the use of cadmium removal bacteria. In this regard, 138 rhizosphere isolates from cacao were examined. Supported by their phenotypic characterization and in vitro cadmium tolerance, three hypertolerant bacteria were selected and identified as members of the Bacillus (S1C2, R1C2) and Pseudomonas (V3C3) genera. They were able to grow normally and reduce the cadmium content under in vitro conditions. However, only S1C2 and R1C2 evidenced to employ intracellular Cd2+ accumulation, suggesting the variability of bacterial detoxification mechanisms. Their bioremediation capacity for Theobroma cacao CCN51 was also analyzed. Surprisingly, we found high detectable levels of Cd2+ in the non-cadmium supplemented control, suggesting an extra source of cadmium in the pot. Moreover, despite their cadmium reduction performance under in vitro conditions, they exerted highly variable outcomes on stem cadmium accumulation. While S1C2 and R1C2 showed a considerable reduction of Cd content in cacao stems, the strain V3C3 did not show any effect on Cd content. This highlights the complexity of the plant–bacteria interactions and the importance of the in vivo test for the selection of promising PGPR bacteria. Overall, our results suggest the cadmium alleviation potential and promising prospects of native Bacillus strains associated with Amazonian cacao.
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48

Brito, Tauane Santos, Renan Pan, Lenir Aparecida Buss, João Paulo Fonesi de Carvalho, Tatiane Eberling, Alexandra Da Silva Martinez, Vandeir Francisco Guimarães, and Elisiane Inês Dall'Oglio Chaves. "Growth Promotion of Burkholderia ambifaria Associated to Nitrogen Fertilization in the Initial Development of Corn." Journal of Agricultural Science 10, no. 6 (May 6, 2018): 123. http://dx.doi.org/10.5539/jas.v10n6p123.

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Growth promoting bacteria are a potential option for sustainable cultivation with lower costs, among them Burkholderia ambifaria, whose importance is mainly due to the endophytic root colonization capacity. The objective of this work was to evaluate the effect of the inoculation of growth promoting bacteria in corn plants, in vitro and in greenhouse, with different levels of nitrogen fertilization. The PIONEER® 30F53 YH maize genotype was inoculated with Burkholderia ambifaria, with 106 CFU per seed, in 12-liter polyethylene pots, filled with commercial substrate, prepared with the different nitrogen contents (N), resulting in treatments with different doses of fertilization, associated or not with bacterial inoculation. After 30 and 45 days, it was evaluated: growth promotion, epiphytic and endophytic population and nitrogen accumulation. In the in vitro experiment, inoculated seeds were cultured in test tubes containing culture medium with absence and presence of nitrogen, evaluated after 7 days. The data were submitted to analysis of variance and the means were compared by the Tukey test at 5% of probability and regression. Increased nitrogen doses in inoculated plants resulted in better morphological parameters at 45 days. In vitro bacterial inoculation, in vitro, influenced the accumulation of fresh weight of shoot, root growth and development of root hair. The endophytic potential and the accumulation of nitrogen were higher in the absence of nitrogen, but lower than the absence of bacteria and the presence of nitrogen.
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49

Tsibakhashvili, N. Ya, L. Mosulishvili, E. Kirkesali, T. Kalabegishvili, S. Kerkenjia, M. V. Frontasyeva, Gh Duca, and I. Zinicovscaia. "Epithermal Neutron Activation Analysis for Bacterial Transformations of Chromium." Chemistry Journal of Moldova 4, no. 2 (December 2009): 8–13. http://dx.doi.org/10.19261/cjm.2009.04(2).18.

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Most powerful primary analytical technique, neutron activation analysis, was applied to study indigenous bacteria, namely, Arthrobacter genera which can be successfully used in detoxification and immobilization of toxic substances. In the present study the effect of Cr(VI) on the elemental content of these bacteria has been examined. The concentrations from 12 to 19 elements such as Na, Al, Cl, K, Fe, Co, Zn, As, Br, Rb, Sr, Sb, Ba, Tb, Th, U were determined in the bacterial cells. The high rate of Cr accumulation in the tested bacterial cells was shown. In bacteria treated with chromate some similarity in the behaviour of the following essential elements − potassium, sodium, chlorine − was observed. Such non-essential elements as Ag, As, Br and U were determined in all bacteria and have to be considered by cells as toxins.
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50

Liao, Juan, An Chun Mo, Hong Kun Wu, Jing Chao Zhang, Yu Bao Li, and Guo Yu Lv. "Antibacterial Activity of Silver-Hydroxyapatite/Titania Nanoparticles on Oral Bacteria." Key Engineering Materials 330-332 (February 2007): 299–302. http://dx.doi.org/10.4028/www.scientific.net/kem.330-332.299.

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Abstract:
Since bacterial accumulation surrounding biomaterials has pathogens known to cause the biomaterials centered infection, it may be important to develop some kind of biomaterial with antibacterial activity as well as biocompatibility. This study focused on evaluating the antibacterial activity of silver-hydroxyapatite/ Titania nanoparticles (Ag-nHA/nTiO2) against oral bacteria with agar dilution method. Bacteria were seeded on agar plate containing antibacterial material with different concentrations after incubation of 48 hours. The antibacterial activity was demonstrated by MICs. The MICs of Ag-nHA/nTiO2 ranged between 1000μg/ ml and 7500μg /ml under anaerobic conditions. And it also exhibited remarkable antibacterial activity to all the aerobe bacteria (MIC≤500μg/ml). On the other hand, the antibacterial activities of Ag-nHA/nTiO2 differentiate to some extent with the bacterial strains. This Ag-nHA/nTiO2 exhibited remarkable antibacterial activity to anaerobic and aerobe bacteria. This antibacterial effect may reduce the potential for bacterial colonisation of oral biomaterials with Ag-nHA/nTiO2.
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