Biphenyl- and carvone-induced protein expression patterns in Rhodococcus sp. ACS

Protein expression patterns in the polychlorinated biphenyl (PCB)-degrading Rhodococcus sp. strain ACS were examined following growth on two substrates capable of inducing the enantioselective biotransformation of PCBs via different degradation pathways. Eleven inducible proteins were identified by SDS-PAGE and characterized by LC-MS/MS. Four of the peptides, a spore coat protein, an extracellular serine protease, a spoVP, and a molecular chaperonin from Bacillus subtilis, were identified as being unique to biphenyl-induced cells, whereas an extracellular serine protease from B. subtilis was identified as being unique to carvone-induced cells. None of the peptides identified had sequences that corresponded to known dioxygenases or other PCB-degrading enzymes of this Grampositive bacterium, suggesting that the identified induced proteins may be involved in either PCB degradation or adaptive responses that protect cells from toxicity.