Coupled Arsenotrophy in a Hot Spring Photosynthetic Biofilm at Mono Lake, California

  title={Coupled Arsenotrophy in a Hot Spring Photosynthetic Biofilm at Mono Lake, California},
  author={Shelley E. Hoeft and Thomas R. Kulp and Sukkyun Han and Brian Lanoil and Ronald S. Oremland},
  journal={Applied and Environmental Microbiology},
  pages={4633 - 4639}
ABSTRACT 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 (∼ 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 photosynthesis but could also readily reduce As(V) to As(III) in the dark at comparable rates. Back-labeling… 

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