ABSTRACT
This chapter summarizes information on the diversity and probable identities of microorganisms that have been cultured from terrestrial subsurface environments. Most of the isolates from the Savannah River Site (SRS) were aerobic chemoheterotrophs, analysis of colony morphological traits implied that there was a considerable amount of diversity within this group of organisms. However, additional research is required to fully assess strain-level diversity among aerobic chemo-heterotrophs from the SRS. Research in the Deep Microbiology Program initially concentrated on the microbiology of saturated Atlantic coastal plain sediments at Department of Energy SRS in Aiken, South Carolina. The most abundant genus among the Rainier Mesa isolates has to be detected among the SRS isolates. To better assess the diversity and possible identity of the aerobic chemoheterotrophs from the SRS site, 16S ribosomal RNA gene nucleotide base sequences were determined and analyzed to learn how the isolates were related phylogenetically to one another and to previously describe bacterial taxa.
