Diversity of Sulfur Isotope Fractionations by Sulfate-Reducing Prokaryotes

ABSTRACT Batch culture experiments were performed with 32 different sulfate-reducing prokaryotes to explore the diversity in sulfur isotope fractionation during dissimilatory sulfate reduction by pure cultures. The selected strains reflect the phylogenetic and physiologic diversity of presently known sulfate reducers and cover a broad range of natural marine and freshwater habitats. Experimental conditions were designed to achieve optimum growth conditions with respect to electron donors, salinity, temperature, and pH. Under these optimized conditions, experimental fractionation factors ranged from 2.0 to 42.0‰. Salinity, incubation temperature, pH, and phylogeny had no systematic effect on the sulfur isotope fractionation. There was no correlation between isotope fractionation and sulfate reduction rate. The type of dissimilatory bisulfite reductase also had no effect on fractionation. Sulfate reducers that oxidized the carbon source completely to CO2 showed greater fractionations than sulfate reducers that released acetate as the final product of carbon oxidation. Different metabolic pathways and variable regulation of sulfate transport across the cell membrane all potentially affect isotope fractionation. Previous models that explained fractionation only in terms of sulfate reduction rates appear to be oversimplified. The species-specific physiology of each sulfate reducer thus needs to be taken into account to understand the regulation of sulfur isotope fractionation during dissimilatory sulfate reduction.

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Effects of Iron and Nitrogen Limitation on Sulfur Isotope Fractionation during Microbial Sulfate Reduction

Applied and Environmental Microbiology ◽

10.1128/aem.01842-12 ◽

2012 ◽

Vol 78 (23) ◽

pp. 8368-8376 ◽

Cited By ~ 33

Author(s):

Min Sub Sim ◽

Shuhei Ono ◽

Tanja Bosak

Keyword(s):

Nitrogen Fixation ◽

Sulfate Reduction ◽

Isotope Fractionation ◽

Sulfur Isotope ◽

Isotope Effects ◽

Reducing Power ◽

Sulfate Reducing ◽

Microbial Sulfate Reduction ◽

Sulfur Isotope Fractionation ◽

S Isotope

ABSTRACTSulfate-reducing microbes utilize sulfate as an electron acceptor and produce sulfide that is depleted in heavy isotopes of sulfur relative to sulfate. Thus, the distribution of sulfur isotopes in sediments can trace microbial sulfate reduction (MSR), and it also has the potential to reflect the physiology of sulfate-reducing microbes. This study investigates the relationship between the availability of iron and reduced nitrogen and the magnitude of S-isotope fractionation during MSR by a marine sulfate-reducing bacterium, DMSS-1, aDesulfovibriospecies, isolated from salt marsh in Cape Cod, MA. Submicromolar levels of iron increase sulfur isotope fractionation by about 50% relative to iron-replete cultures of DMSS-1. Iron-limited cultures also exhibit decreased cytochromec-to-total protein ratios and cell-specific sulfate reduction rates (csSRR), implying changes in the electron transport chain that couples carbon and sulfur metabolisms. When DMSS-1 fixes nitrogen in ammonium-deficient medium, it also produces larger fractionation, but it occurs at faster csSRRs than in the ammonium-replete control cultures. The energy and reducing power required for nitrogen fixation may be responsible for the reverse trend between S-isotope fractionation and csSRR in this case. Iron deficiency and nitrogen fixation by sulfate-reducing microbes may lead to the large observed S-isotope effects in some euxinic basins and various anoxic sediments.

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The effect of temperature on sulfur and oxygen isotope fractionation by sulfate reducing bacteria (Desulfococcus multivorans)

FEMS Microbiology Letters ◽

10.1093/femsle/fnaa061 ◽

2020 ◽

Vol 367 (9) ◽

Author(s):

André Pellerin ◽

Gilad Antler ◽

Angeliki Marietou ◽

Alexandra V Turchyn ◽

Bo Barker Jørgensen

Keyword(s):

Sulfate Reduction ◽

Oxygen Isotope ◽

Isotope Fractionation ◽

Sulfur Isotope ◽

Sulfate Reducing Bacteria ◽

Oxygen Isotope Fractionation ◽

Sulfate Reducing ◽

Sulfur Isotope Fractionation ◽

Reducing Bacteria ◽

Desulfococcus Multivorans

ABSTRACT Temperature influences microbiological growth and catabolic rates. Between 15 and 35 °C the growth rate and cell specific sulfate reduction rate of the sulfate reducing bacterium Desulfococcus multivorans increased with temperature. Sulfur isotope fractionation during sulfate reduction decreased with increasing temperature from 27.2 ‰ at 15 °C to 18.8 ‰ at 35 °C which is consistent with a decreasing reversibility of the metabolic pathway as the catabolic rate increases. Oxygen isotope fractionation, in contrast, decreased between 15 and 25 °C and then increased again between 25 and 35 °C, suggesting increasing reversibility in the first steps of the sulfate reducing pathway at higher temperatures. This points to a decoupling in the reversibility of sulfate reduction between the steps from the uptake of sulfate into the cell to the formation of sulfite, relative to the whole pathway from sulfate to sulfide. This observation is consistent with observations of increasing sulfur isotope fractionation when sulfate reducing bacteria are living near their upper temperature limit. The oxygen isotope decoupling may be a first signal of changing physiology as the bacteria cope with higher temperatures.

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Sulfur Isotope Fractionation by Sulfate-Reducing Microbes Can Reflect Past Physiology

Environmental Science & Technology ◽

10.1021/acs.est.7b05119 ◽

2018 ◽

Vol 52 (7) ◽

pp. 4013-4022 ◽

Cited By ~ 3

Author(s):

André Pellerin ◽

Christine B. Wenk ◽

Itay Halevy ◽

Boswell A. Wing

Keyword(s):

Isotope Fractionation ◽

Sulfur Isotope ◽

Sulfate Reducing ◽

Sulfur Isotope Fractionation

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Interactions between filamentous sulfur bacteria, sulfate reducing bacteria and poly-P accumulating bacteria in anaerobic-oxic activated sludge from a municipal plant

Water Science & Technology ◽

10.2166/wst.1998.0725 ◽

1998 ◽

Vol 37 (4-5) ◽

pp. 599-603 ◽

Cited By ~ 4

Author(s):

Ryoko Yamamoto-Ikemoto ◽

Saburo Matsui ◽

Tomoaki Komori ◽

Edja. Kofi. Bosque-Hamilton

Keyword(s):

Activated Sludge ◽

Sulfate Reduction ◽

Reduction Rate ◽

Sulfate Reducing Bacteria ◽

Sulfate Reduction Rate ◽

Filamentous Bulking ◽

Sulfate Reducing ◽

Sulfur Bacteria ◽

Sulfate Reduction Rates ◽

Reducing Bacteria

The interactions between filamentous sulfur bacteria (FSB), sulfate reducing bacteria (SRB) and poly-P accumulating bacteria (PAB) in the activated sludge of a municipal plant operated under anaerobic-oxic conditions were examined in batch experiments using return sludge (RAS) and settled sewage. Phosphate release and sulfate reduction occurred simultaneously under anaerobic conditions. SRB were more sensitive to temperature changes than PAB. SRB played an important role in the decomposition of propionate to acetate. When the sulfate reduction rates were high, there was a tendency for the maximum release of phosphate also to be high. This was explained by the fact that PAB utilized the acetate produced by SRB. Sulfur oxidizing bacteria were sensitive to temperature change. When the sulfate reduction rate was high, the sulfide oxidizing rate was also high and filamentous bulking occurred. The results showed that sulfate reduction was a cause of filamentous bulking due to Type 021N that could utilize reduced sulfur.

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Controls on stable sulfur isotope fractionation during bacterial sulfate reduction in Arctic sediments

Geochimica et Cosmochimica Acta ◽

10.1016/s0016-7037(00)00557-3 ◽

2001 ◽

Vol 65 (5) ◽

pp. 763-776 ◽

Cited By ~ 83

Author(s):

Volker Brüchert ◽

Christian Knoblauch ◽

Bo Barker Jørgensen

Keyword(s):

Sulfate Reduction ◽

Isotope Fractionation ◽

Sulfur Isotope ◽

Bacterial Sulfate Reduction ◽

Sulfur Isotope Fractionation ◽

Stable Sulfur Isotope

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The effect of pantothenate on sulfate metabolism and sulfur isotope fractionation by Saccharomyces cerevisiae

Canadian Journal of Microbiology ◽

10.1139/m79-177 ◽

1979 ◽

Vol 25 (10) ◽

pp. 1139-1144 ◽

Cited By ~ 1

Author(s):

R. G. L. McCready ◽

G. A. Din ◽

H. R. Krouse

Keyword(s):

Saccharomyces Cerevisiae ◽

Fatty Acids ◽

Sulfate Reduction ◽

Lipid Content ◽

Isotope Fractionation ◽

Sulfur Isotope ◽

Unsaturated Fatty Acids ◽

Cellular Lipid ◽

Sulfur Isotope Fractionation ◽

Sulfate Metabolism

Growth of Saccharomyces cerevisiae in minimal salts – glucose – SO42− medium with varying concentrations of pantothenate (0–1000 μg/L) produced changes in the cellular lipid content and in the ratio of saturated to unsaturated fatty acids. Substantial differences in SO42−diffusion were also observed with changes in pantothenate concentration. During sulfate reduction, the δ34S value of the evolved sulfide varied with the pantothenate concentration ranging from −31‰ in the absence of pantothenate to 0‰ at 400−1000 μg/L pantothenate. The isotope selectivity is related to the effect of pantothenate concentration on cellular metabolism.

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Salinity Responses of Benthic Microbial Communities in a Solar Saltern (Eilat, Israel)

Applied and Environmental Microbiology ◽

10.1128/aem.70.3.1608-1616.2004 ◽

2004 ◽

Vol 70 (3) ◽

pp. 1608-1616 ◽

Cited By ~ 78

Author(s):

Ketil Bernt SÃ¯Â¿Â½rensen ◽

Donald E. Canfield ◽

Aharon Oren

Keyword(s):

Sulfate Reduction ◽

Reduction Rate ◽

Sulfate Reduction Rate ◽

Anoxygenic Phototrophs ◽

Sulfate Reducing ◽

Oxygen Budget ◽

Reducing Bacteria ◽

Increased Activity ◽

Optimum Salinity

ABSTRACT The salinity responses of cyanobacteria, anoxygenic phototrophs, sulfate reducers, and methanogens from the laminated endoevaporitic community in the solar salterns of Eilat, Israel, were studied in situ with oxygen microelectrodes and in the laboratory in slurries. The optimum salinity for the sulfate reduction rate in sediment slurries was between 100 and 120‰, and sulfate reduction was strongly inhibited at an in situ salinity of 215‰. Nevertheless, sulfate reduction was an important respiratory process in the crust, and reoxidation of formed sulfide accounted for a major part of the oxygen budget. Methanogens were well adapted to the in situ salinity but contributed little to the anaerobic mineralization in the crust. In slurries with a salinity of 180‰ or less, methanogens were inhibited by increased activity of sulfate-reducing bacteria. Unicellular and filamentous cyanobacteria metabolized at near-optimum rates at the in situ salinity, whereas the optimum salinity for anoxygenic phototrophs was between 100 and 120‰.

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