1 item with the tag “hot springs

  • Project 1D: Potential for Microbial Iron Reduction in Chocolate Pots Hot Springs, Yellowstone National Park
    NAI 2013 University of Wisconsin Annual Report

    Iron biogeochemical cycling in circumneutral pH hot spring systems is an increasingly important astrobiological target, given recent discoveries on Mars by Curiosity. This study explored the potential for microbial reduction of ferric iron Fe(III) in the warm (ca. 40-60 C), circumneutral pH (ca. 6.0-6.5) Chocolate Pots (CP) hot springs in Yellowstone National Park. Endogenous microbial communities were able to reduce native CP Fe(III) oxides, as documented in most probable number (MPN) enumerations and ongoing enrichment culture studies. Microbial communities in the enrichments have been analyzed by high-throughput pyrosequencing of 16S rRNA gene amplicons. The sequencing revealed an abundance of the well-known Fe(III)-reducing bacterial species, Geobacter metallireducens, as well several other novel organisms with the potential to contribute to Fe(III) reduction. A shotgun metagenomic (paired-end Illumina sequencing) analysis of the enrichment cultures is in progress to explore the identity and function of G. metallireducens as well as other less well-characterized organisms in the cultures. Of particular interest are the likely presence of thermotolerance genes in the G. metallireducens metagenome, as well as outer membrane cytochrome genes that may be indicative of other Fe(III)-reducing organisms and provide evidence for pathways of electron flow in these cultures.

    ROADMAP OBJECTIVES: 2.1 5.1 6.1 7.1