Degradation with sulfate reduction

Degradation with Sulfate Reduction. Equation 11 describes CP degradation coupled to sulfate reduction. 

Haggblom, M.M. and Young, L.Y. Chlorophenol degradation coupled with sulfate reduction, Appl Environ. Microbiol, 56(ll) 3255-3260, 1990. 

PHA synthesis has been advanced as an energy-producing mechanism in anaerobic syntrophic (H2-producing, acetogenic) bacteria [159]. Extracellular PHBV degradation concurrent with sulfate reduction in anoxic lake-sediment samples was seen by Urmeneta et al. [160] as an indication that PHAs could serve as carbon and electron sources. 

There is evidence for the anaerobic degradation of alkanes to COj, plausibly under conditions of sulfate reduction. In experiments with sediment slurries from contaminated marine areas, was recovered from " C-hexadecane (Coates et al. 1997), and was inhibited by molybdate that is consistent with the involvement of sulfate reduction. Under sulfate-reducing conditions was produced from C[14,15]octacosane (CagHjg) (Caldwell et al. 1998). Different mechanisms have been elucidated for the anaerobic degradation of higher alkanes, and both occurred simultaneously in a sulfate-reducing consortium (Callaghan et al. 2006) ... 

This is useful, albeit basic, information for an ES working in the domain of sick cars. If you are employed as a car mechanic, you are not likely to benefit from, or even be interested in, the presence within the knowledge base of details about how lead sulfate batteries degrade with age and how any diminution in concentration of the active materials in the battery can be related through the Nernst equation to a reduction in its voltage. In the context of car repair, all that you need to know is that the battery is dead and the car will not start, so it will need replacing or recharging. 

Heath and Ghalamboi29 31 had obtained a 2-deoxyheptose of unknown configuration by degradation with ceric sulfate of 15 (see Scheme 8), the product obtained upon reduction of KDO with sodium borohydride. Perry and Adams94 had shown this 2-deoxyheptose to be identical with 2-deoxy-D-manno-heptose (62 see Scheme 18), synthesized by Perry.91... 

You work in a research laboratory and your job is to investigate the microbial degradation of organic pollutants in laboratory aquifer column systems. You supply a column continuously with a synthetic groundwater containing 0.3 mM 02, 0.5 mM NOj, 0.5 mM SO -, and 1 mM HCOj, as well as 0.1 mM benzoic acid butyl ester, which is easily mineralized to C02 and H20. The temperature is 20°C and the pH is 7.3 (well buffered). Would you expect sulfate reduction or even methanogenesis to occur in this column Establish an electron balance to answer this question. 

As with nitrate, the anaerobic biodegradation of m- and /-xylene could also be linked with the reduction of sulfate at a rate of about 1 /M/day. Edwards et al. (1992) demonstrated the sulfate-dependent degradation of all three xylene isomers. Interestingly, the xylenes were not degraded until toluene was almost depleted. 

In contrast, in shallow reservoirs bacterial sulfate reduction may occur with degradation of the crude oil (Bailey et al., 1973). The sulphate reducers may not be able to use petroleum per se but only with the participation of petroleum-oxidizing aerobes, transported by freshwater recharge, to provide suitable carbon sources for the sulfate-reducers (see Chapter 6.1). 

Biological factors play many roles in the cycling of sulfur minerals associated with fossil fuels. Sulfate reduction may lead to the solution of eva-porite sulfates while production of sulfide ions at various stages in the formation and degradation of fossil fuels may lead to deposition of sulfide minerals or elemental sulfur (see Chapter 6.2). 

Rates of methane production via both acetate fermentation and C02 reduction were directly measured with radiotracer techniques in the sulfate-depleted sediments of Saanich and Princess Louisa Inlets (Kuivila etal., 1990). Comparison of measured and modeled rates suggests that these two pathways account for the majority of methane produced below the sulfate reduction zone in the sediments of both the basins. Prior aerobic degradation of the organic matter has little influence on the pathways of methane production. 

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