Aerobic Hydrocarbon-Degrading Alphaproteobacteria: Rhodobacteraceae (Roseobacter)

Abstract

Members of the Roseobacter lineage of bacteria are prevalent in diverse marine environments where they carry out critical biogeochemical processes. Recent reports, based primarily on culture-independent studies and reviewed here, provide compelling evidence that members of this abundant lineage are involved in hydrocarbon degradation in natural systems. Five distinct pathways for the aerobic degradation of aromatic compounds are commonly identified in Roseobacter genomes, as are genes encoding alkane hydroxylases and uncharacterized ring-cleaving and ring-hydroxylating dioxygenases. Taken together, these findings suggest roseobacters, a group historically over-looked with regard to this physiology, may play important roles in the degradation of hydrocarbons at both naturally occurring and elevated levels in marine environments.