Comment on "Arsenic (III) fuels anoxygenic photosynthesis in hot spring biofilms from Mono Lake, California".
نویسندگان
چکیده
Kulp et al. (Reports, 15 August 2008, p. 967) described a bacterium able to photosynthetically oxidize arsenite [As(III)] via arsenate [As(V)] reductase functioning in reverse. Based on their phylogenetic analysis of As(V) reductase, they proposed that this enzyme was responsible for the anaerobic oxidation of As(III) in the Archean. We challenge this proposition based on paleogeochemical, bioenergetic, and phylogenetic arguments.
منابع مشابه
Arsenic(III) fuels anoxygenic photosynthesis in hot spring biofilms from Mono Lake, California.
Phylogenetic analysis indicates that microbial arsenic metabolism is ancient and probably extends back to the primordial Earth. In microbial biofilms growing on the rock surfaces of anoxic brine pools fed by hot springs containing arsenite and sulfide at high concentrations, we discovered light-dependent oxidation of arsenite [As(III)] to arsenate [As(V)] occurring under anoxic conditions. The ...
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Red-pigmented biofilms grow on rock and cobble surfaces present in anoxic hot springs located on Paoha Island in Mono Lake. The bacterial community was dominated ( approximately 85% of 16S rRNA gene clones) by sequences from the photosynthetic Ectothiorhodospira genus. Scraped biofilm materials incubated under anoxic conditions rapidly oxidized As(III) to As(V) in the light via anoxygenic photo...
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Three novel strains of photosynthetic bacteria from the family Ectothiorhodospiraceae were isolated from soda lakes of the Great Basin Desert, USA by employing arsenite (As(III)) as the sole electron donor in the enrichment/isolation process. Strain PHS-1 was previously isolated from a hot spring in Mono Lake, while strain MLW-1 was obtained from Mono Lake sediment, and strain BSL-9 was isolate...
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عنوان ژورنال:
- Science
دوره 323 5914 شماره
صفحات -
تاریخ انتشار 2009