Sulfur to sulfidic

The anaerobic degradation of halogenated alkanoic acids has, however, been much less exhaustively examined. Geobacter (Trichlorobacter) thiogenes was able to transform trichloroacetate to dichloroacetate by coupling the oxidation of acetate to CO2 with the reduction of sulfur to sulfide that carries out the dechlorination (De Wever et al. 2000). 

Sulfide oxidation by phototrophic bacteria is catalyzed by c-type cytochromes, flavocytochromes and even cytochrome c complexes (see 4.2). A heat-labile cytochrome c-550 of Thiocapsa roseopersicina is responsible for the oxidation of sulfide. The end product is elemental sulfur and it is assumed that this cytochrome might also catalyze the reverse reaction by reducing the intracellularly stored elemental sulfur to sulfide (4.9V... 

Ash and Total Sulfur Analyses. Samples were removed from the specimens and submitted for ash and total sulfur analysis to Schwartzkopf Microanalytical Laboratory, Woodside, N.Y. 11377. For ashing, samples were burned under oxygen at 900-1000°C for ca one half hour. For sulfur, samples were treated with potassium metal to convert sulfur to sulfides, followed by conversion to methylene blue for spectrophotometrlc analysis (at 670 nm). Except for very small samples (less than 0.2mg), values for ash and sulfur have an uncertainty of ca 10% of the reported values. 

The convenient route to [Fe4S4(SR)4]2, using FeCl3, RS and sulfur, depends on thiolate reducing half of the iron(III) to iron(II), and all of the sulfur to sulfide. As a result more thiolate is required than with procedures starting with sulfide ion. This requirement can be reduced by using an iron(II) salt765 rather than iron(III). The overall reaction is then as in equation (70). 

In laboratory studies, many assimilatory microorganisms release HjS during growth on sodium sulfite as their sole sulfur source (Kaplan and Rit-tenberg, 1964 Krouse et al., 1967 McCready et al., 1974, 1975). For over a century, numerous studies have attested to the reduction of elemental sulfur to sulfide by many microorganisms, plants and animal tissue (Roy and Tru-... 

It was apparent that there was a lack of conclusive data to establish a mechanism for the reduction of sulfur to sulfide in the LiCl-KCl eutectic. In addition, this type of information was needed so that further improve-... 

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