Proteome analysis of Acinetobacter radioresistens reveals proteins involved in aromatic compounds uptake and degradation.

A fast phenol degrading Acinetobacter radioresistens strain was isolated in our laboratories and selected for bioremediation applications. This bacterium is also able to grow on benzoate and catechol as sole carbon-energy sources, metabolizing them via the ortho route. In previous researches we detected, by means of proteome analysis, some marker enzymes of the phenol and benzoate degradative pathways. In the present work we extend the identification of the proteins involved in the aromatic-ring opening (the different components of the phenol hydroxylase and benzoate dioxygenase, the catechol dioxygenase isozymes) together with other satellite proteins specifically induced by the aromatic growth substrate. Of these last proteins some are probably related to the cellular uptake of benzoate and phenol while others are ascribed to the GroEL family of heat-shock chaperonines, involved in proteins processing and folding. Aromatic substrates may thus act as stress-agents like heat or cold.