Horizontal gene transfer in Oral bacteria
from: Molecular Oral Microbiology (Edited by: Anthony H. Rogers). Caister Academic Press, U.K. (2008)
Analyses of gene phylogenies and DNA-composition reveal that an important source of genetic innovation in prokaryotes is the transfer of sequences from other bacteria. The advent of genomic data now allows determination of the importance of horizontally-transferred genes on a genomic scale. By comparative analysis of fully- sequenced oral bacteria and between them and non-oral relatives, it is clear that horizontal gene transfer (HGT) is extremely frequent in oral pathogens and that this process probably also takes place also between bacteria and oral fungi. It is likely that HGT is facilitated, in oral biofilms such as dental plaque, by the close physical contact between phylogenetically distant bacteria. . In some cases, certain sets of genes are shared between more than two species co-inhabiting the mouth ecosystem, supporting the idea that there is an environment-associated gene pool formed by sequences of special adaptive importance. This habitat gene reservoir is also present in other natural ecosystems. A survey of HGT in oral bacteria is presented, as well as the evolutionary and biological consequences of this process.From the applied viewpoint, some of these genes could be potential vaccine candidates, targeting more than one potentially pathogenic species read more ...