Bacterial exopolymer and PHB production in fluctuating ground-water habitats

Bengtsson, Göran

doi:10.1016/0378-1097(91)90684-3

Cited by 6 publications

(8 citation statements)

References 41 publications

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“…Surface accessibility. Addition of bacterial biomass and production of extracellular bacterial polymers (3,25,48) may alter the ability of Norbome soil to sorb chemicals. This soil has a low organic carbon content (0.16%), and electrostatic interactions are primarily associated with the 2:1 clay interlayer positions.…”

Section: Discussionmentioning

confidence: 99%

Impact of Bacterial Biomass on Contaminant Sorption and Transport in a Subsurface Soil

Bellin

Rao

1993

Appl Environ Microbiol

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The objective of this study was to investigate the impact of bacterial biomass on the sorption and transport of three solutes (quinoline, naphthalene, and 45Ca) in a subsurface soil. Miscible displacement techniques were employed to measure sorption and transport of the above compounds during steady, saturated water flow in sterile and/or bacterium-inoculated soil columns. The soil was inoculated with either a quinoline-degrading bacterium, Pseudomonas sp. 3N3A isolate, or its mutant isolate, B53, which does not degrade quinoline. In soil columns inoculated with the B53 and 3N3A isolates, quinoline sorption was reduced by about 60 and 20%o, respectively. In contrast, 45Ca sorption was minimally reduced, which indicated that biomass did not significantly alter the cation-exchange capacity of the soil. Biomass impacts on sorption were solute specific, even when the sorption mechanism for both quinoline and 45Ca was similar. Thus, the differential response is attributed to biomass-induced changes in quinoline speciation; an increase in pH at the sorbent-water interface would result in a larger proportion of the neutral species and a decrease in sorption. Sorption of naphthalene was reduced by about 30%o, which was attributed to accessibility of hydrophobic regions. Minimal biosorption of all solutes indicated negligible biofacilitated transport. Alteration of the soil surfaces upon addition of bacterial biomass reduced sorption of quinoline and naphthalene, thereby enhancing transport.

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Section: Discussionmentioning

confidence: 99%

Impact of Bacterial Biomass on Contaminant Sorption and Transport in a Subsurface Soil

Bellin

Rao

1993

Appl Environ Microbiol

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“…Generally, the concentration of dissolved Fe(U) did not increase in the incubated samples from the northern cluster, although the level of dissolved Fe(I1) (21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)(36) pg Fe(II)/gdw) was higher (Fig. 4A).…”

Section: Microbial Fe(iii)-reductionmentioning

confidence: 92%

“…2). The absence of tram isomers of PLFA's and of storage lipid (poly /3-hydroxy butyric acid, PHB) [21,33] suggests that the microbial community was not under severe stress or nutritional limitation, and as expected from the relatively oligotrophic environment, the populations seem to be growing but not in the logarithmic growth phase.…”

Section: Sediment Microbiologymentioning

confidence: 99%

Limiting factors for microbial Fe(III) -reduction in a landfill leachate polluted aquifer (Vejen, Denmark)

Albrechtsen

1995

FEMS Microbiology Ecology

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Aquifer sediment samples from two locations within the anaerobic leachate plume of a municipal landfill were compared with respect to microbiology (especially Fe(III)-reduction) and geochemistry. The samples close to the landfill were characterized by low contents of Fe(III), whereas samples from the more distant cluster were rich in Fe(III)-oxides. The active microbial population seemed to be less dense in samples more distant from the landfill (measured by ATP and phospholipid fatty acids (PLFA)), but the microbial communities were very similar in the two sample clusters according to the composition of PLFA. Very little, if any, Fe(III)-reduction was observed close to the landfill, but all the more distant samples showed evident microbially mediated Fe(III)-reduction. After amendment with both acetate and Fe(III), all the samples showed a potential for Fe(III)-reduction, and the in situ Fe(III)-reduction seemed to be limited by the lack of Fe(III)-availability. It was suggested, that Fe(III)-reducing populations might be facultative, surviving by use of other electron-acceptors than Fe(III), when Fe(II1) is not available for reduction.

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“…Bacteria may adhere to surfaces and grow as sessile biofilm communities in response to oligotrophic (low-nutrient) conditions (18,26). Low nutrient concentrations may also stimulate production of EPS by both sessile and planktonic cells (4). The attached cells are usually associated with greater amounts of EPS than are planktonic cells (4,37).…”

mentioning

confidence: 99%

Bioaccumulation of the Herbicide Diclofop in Extracellular Polymers and Its Utilization by a Biofilm Community during Starvation

Wolfaardt¹,

Lawrence²,

Robarts³

et al. 1995

Appl Environ Microbiol

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Continuous-flow cell systems were used to cultivate a degradative biofilm community with the herbicide diclofop methyl as the sole carbon and energy source. The aromatic character of this compound and its breakdown products enabled direct visualization of their accumulation in the biofilm matrix. This accumulation could be inhibited by addition of a more labile carbon source to the culture medium or by inhibition of cell activity. The fluorescence of diclofop-grown biofilms remained constant after 14 to 21 days but decreased with time when diclofop was omitted from the irrigation solution. However, this decrease was inhibited by cyanide, indicating either utilization or release of accumulated diclofop when the cells were viable. Subsequent experiments with [ 14 C]diclofop also indicated that decreased fluorescence in the absence of an exogenous carbon source resulted from degradation of adsorbed diclofop and its breakdown products by the biofilm bacteria. These results demonstrate that biofilm exopolymers can facilitate storage of nutrients for subsequent mineralization during periods of carbon limitation.

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Bacterial exopolymer and PHB production in fluctuating ground-water habitats

Cited by 6 publications

References 41 publications

Impact of Bacterial Biomass on Contaminant Sorption and Transport in a Subsurface Soil

Impact of Bacterial Biomass on Contaminant Sorption and Transport in a Subsurface Soil

Limiting factors for microbial Fe(III) -reduction in a landfill leachate polluted aquifer (Vejen, Denmark)

Bioaccumulation of the Herbicide Diclofop in Extracellular Polymers and Its Utilization by a Biofilm Community during Starvation

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