Cell surface properties and fatty acids composition of Stenotrophomonas maltophilia under the influence of hydrophobic compounds and surfactants.

Surface properties of newly isolated Stenotrophomonas maltophilia strain 6 were tested. The bacteria were stored in two different ways to determine the influence of hydrocarbons and surfactants on surface and enzymatic characteristics of the isolated strain. The influence of surface active agents, natural and synthetic, on membrane's lipid composition and cell surface hydrophobicity (CSH) was investigated. Our results indicate that long-term contact with diesel oil as a hydrophobic sole carbon source leads to the increased enzymatic activity of S. maltophilia strain 6 as well as to modification of fatty acids profiles and its facility to adhere to hydrophobic compounds. Among surfactants there were saponins and Triton X-100 which changed the composition of fatty acids the most, increasing the amount of branched acids. The comparison of fatty acid profiles with CSH of systems with diesel oil, rhamnolipids, saponins and Triton X-100 points out that the growing amount of hydroxy fatty acids corresponds to lower hydrophobicity. Moreover, CSH is a dynamic parameter which can change during cultivation of microorganisms.