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34S/32S fractionation in sulfur cycles catalyzed by anaerobic bacteriaStable isotopic distributions in the sulfur cycle were studied with pure and mixed cultures of the anaerobic bacteria, Chlorobium vibrioforme and Desulfovibrio vulgaris. D. vulgaris and C. vibrioforme can catalyze three reactions constituting a complete anaerobic sulfur cycle: reduction of sulfate to sulfide (D. vulgaris), oxidation of sulfide to elemental sulfur (C. vibrioforme), and oxidation of sulfur to sulfate (C. vibrioforme). In all experiments, the first and last reactions favored concentration of the light 32S isotope in products (isotopic fractionation factor epsilon = -7.2 and -1.7%, respectively), whereas oxidation of sulfide favored concentration of the heavy 34S isotope in products (epsilon = +1.7%). Experimental results and model calculations suggest that elemental sulfur enriched in 34S versus sulfide may be a biogeochemical marker for the presence of sulfide-oxidizing bacteria in modern and ancient environments.
Document ID
20040112263
Document Type
Reprint (Version printed in journal)
Authors
Fry, B. (Indiana University Bloomington 47405, United States)
Gest, H.
Hayes, J. M.
Date Acquired
August 21, 2013
Publication Date
January 1, 1988
Publication Information
Publication: Applied and environmental microbiology
Volume: 54
Issue: 1
ISSN: 0099-2240
Subject Category
Life Sciences (General)
Funding Number(s)
CONTRACT_GRANT: PCM-84-04996
CONTRACT_GRANT: DMB 841 5291
CONTRACT_GRANT: NGR15003-118
Distribution Limits
Public
Copyright
Other
Keywords
Non-NASA Center
NASA Discipline Exobiology
NASA Program Exobiology
NASA Discipline Number 52-30