The diversity of prokaryotes associated with humans has been dominated by uncultured species (not isolated in pure culture). For instance, nearly 80% of the human gut and 68% of the human oral microbes are thought to be uncultured; some of which have been associated with human oral, digestive, vaginal, and cardiovascular diseases. The revalence of uncultured pathogens is expected to continue to increase within the near future. In fact, public databases such as GenBank have nearly quadrupled the number of candidate phyla (those made entirely of uncultured organisms) since the 1980s and currently lists many new lineages of unclassified Bacteria and Archaea. Because detection of uncultured organisms has been limited to the 16S rDNA gene sequence, little is known about the function (e.g. pathogenicity) they play in humans. Access to human samples, however, imposes limitations to reproducible data and alternative models have been proposed. The work here presented attempts to further characterize the uncultured bacteria in the TM7 Candidate Division using both cultured-independent molecular and cultivation methods. Our long-term goal is to investigate how environmental strains of TM7 can serve as potential model organisms to help us determine the role uncultured bacteria play in humans.
Michael Abrams, David Barton, Eamon Vandaei, Diana Romero, Adam Caldwell, and Cleber Ouverney. "Genomic Characteristics of an Environmental Microbial Community Harboring a Novel Human Uncultured TM7 Bacterium Associated with Oral Diseases" Faculty Publications (2012). DOI: 10.4172/scientificreports.276