Under seasonally fluctuating redox conditions in sediment of Kiel Bay (eastern Baltic Sea), viable counts (MPN) of sulfate-reducing bacteria (SRB) ranged between 4 X 102 and 7 X 104 cm-3 These MPN appeared fairly independent of ambient redox potentials and followed peaks of phytoplankton productivity in the water column with a time lag of 2 to 3 wk. The relative proportions of SRB using acetate...

Denitrifying and anammox bacteria are involved in the nitrogen cycling in marine sediments but the environmental factors that regulate the relative importance of these processes are not well constrained. Here, we evaluated the abundance, diversity, and potential activity of denitrifying, anammox, and sulfide-dependent denitrifying bacteria in the sediments of the seasonally hypoxic saline Lake ...

Correlation between hydrogen isotope fractionation in fatty acids and carbon metabolism in pure cultures of bacteria indicates the potential of biomarker D/H analysis as a tool for diagnosing carbon substrate usage in environmental samples. However, most environments, in particular anaerobic habitats, are built from metabolic networks of micro-organisms rather than a single organism. The effect...

The relative abundance of different groups of sulphate-reducing bacteria (SRB) in faecal DNA collected before and after therapy from patients suffering from Crohn's disease (CD), irritable bowel syndrome (IBS) or ulcerative colitis (UC) has been compared with that from healthy controls. Growth tests revealed that SRB were not more abundant in samples from patients with CD before treatment than ...

−The inhibition of methane production in the continuous anaerobic degradation process for the treatment of sewage sludge containing sulfate was investigated. Also, the competition between sulfate-reducing bacteria (SRB) and methane-producing bacteria (MPB) with COD/sulfate ratio was explained in terms of electron flow. The methane production rate was 0.07, 0.13, 0.24, 0.31 and 0.33 l-CH4 g-COD ...

A mixed culture of human fecal bacteria was grown for 120 days in a three-stage continuous culture system. To reproduce some of the nutritional and pH characteristics of the large gut, each vessel had a different operating volume (0.3, 0.5, and 0.8 liter) and pH (6.0, 6.5, and 7.0). A mixture of polysaccharides and proteins was used as carbon and nitrogen sources. Measurements of H2, CH4, S2-, ...

Biofilms of sulfate-reducing bacteria (SRB) are of particular interest as members of this group are culprits in corrosion of industrial metal and concrete pipelines as well as being key players in subsurface metal cycling. Yet the mechanism of biofilm formation by these bacteria has not been determined. Here we show that two supposedly identical wild-type cultures of the SRB Desulfovibrio vulga...

Biocorrosion, also known as microbiologically influenced corrosion (MIC), is caused by various corrosive biofilms. So far, laboratory experimental MIC pitting tests in the published literature have overwhelmingly focused on sulfate reducing bacteria (SRB) that use sulfate as the terminal electron acceptor because SRB and sulfate are often found at anaerobic pitting sites. Many laboratory pure-c...

We tracked the changes in water chemistry (major and trace elements, S isotope compositions, pH, Eh) and At the Sanders Lead car-battery recycling plant, near Troy, AL, identified solid “mineral” phases produced by biochemigroundwater is highly acidic (pH varies from 3 to 3.5) and carries cal processes. Theoretical geochemical modeling was high concentrations of Pb, Cd, Zn, Cu, and Fe. Pilot fi...

We describe the combined application of microsensors and molecular techniques to investigate the development of sulfate reduction and of sulfate-reducing bacterial populations in an aerobic bacterial biofilm. Microsensor measurements for oxygen showed that anaerobic zones developed in the biofilm within 1 week and that oxygen was depleted in the top 200 to 400 &mgr;m during all stages of biofil...