The purpose of this study was to investigate some parameters of S. marcescens IBBPo15 cells adaptation to toxic organic solvents. S. marcescens IBBPo15 cells incubated at 37°C exhibited a slower growth when they were exposed to 5% organic solvents (alkanes, aromatics), as compared with the control cells. S. marcescens IBBPo15 cells grown at 37°C produced protease and the enzyme production decreased in cells exposed to aromatic compounds, as compared with the control cells. Surfactant serrawettin and red pigment prodigiosin were produced by S. marcescens IBBPo15 cells grown at 37°C. Modifications in the pigment and extracellular proteins profile were observed in S. marcescens IBBPo15 cells grown at 37°C during exposure to organic solvents (alkanes, aromatics). Alkane hydroxylase (i.e., alkB1) and toluene dioxygenase (i.e., todM) catabolic genes, 4'-phosphopantetheinyl transferase (i.e., pswP) and serralysin metalloproteinase (i.e., ser) genes were detected by polymerase chain reaction in DNA extracted from S. marcescens IBBPo15 control cells grown at 37°C, as well as in cells exposed to organic solvents (excepting todM in n-decane exposed cells).