The production of 34S-depleted sulfide during bacterial disproportionation of elemental sulfur.
Bacteria that disproportionate elemental sulfur fractionate sulfur isotopes such that sulfate is enriched in sulfur-34 by 12.6 to 15.3 per mil and sulfide is depleted in sulfur-34 by 7.3 to 8.6 per mil. Through a repeated cycle of sulfide oxidation to S0 and subsequent disproportionation, these bacteria can deplete sedimentary sulfides in sulfur-34. A prediction, borne out by observation, is that more extensive sulfide oxidation will lead to sulfides that are more depleted in sulfur-34. Thus, the oxidative part of the sulfur cycle creates circumstances by which sulfides become more depleted in sulfur-34 than would be possible with sulfate-reducing bacteria alone.
Canfield
D E
DE
Max Planck Institute for Marine Microbiology, Bremen, Germany.
Thamdrup
B
B
D003718:Denmark; D005290:Ferric Compounds; D019015:Geologic Sediments / Q000382:microbiology*; D005858:Germany; D009792:Oceans and Seas; D010084:Oxidation-Reduction; D013440:Sulfides / Q000378:metabolism*; D013455:Sulfur / Q000378:metabolism*; D013460:Sulfur Isotopes; D016999:Sulfur-Reducing Bacteria / Q000378:metabolism*; D014871:Water Microbiology
D005290:Ferric Compounds; D013440:Sulfides; D013460:Sulfur Isotopes; D013455:Sulfur