Linear alkanesulfonates as carbon and energy sources for gram-positive andgram-negative bacteria

Several bacteria from soil and rainwater samples were enriched and isolated with propanesulfonate or butanesulfonate as sole carbon and energy source. Most of the strains isolated utilized nonsubstituted alkanesulfonates with a chain length of C3-C6 and the substituted sulfonates taurine and isethio nate as carbon and energy source. A gram-positive isolate, P40. and a gram- negative isolate. P53, were characterized in more detail. Phylogenetic anal ysis grouped strain P40 within group IV of the genus Rhodococcus and showed a close relationship with Rhodococcus opacus. After phylogenetic and physi ological analyses, strain P53 was identified as Comamonas acidovorans . Bot h bacteria also utilized a wide range of sulfonates as sulfur source. Strai n P40, but not strain P53, released sulfite into the medium during dissimil ation of sulfonated compounds. Cell-free extracts of strain P53 exhibited h igh sulfite oxidase activity [2.34 U (mg protein)(-1)] when assayed with fe rricyanide, but not with cytochrome c. Experiments with whole-cell suspensi ons of both strains showed that the ability to dissimilate 1-propanesulfona te was specifically induced during growth on this substrate and was not pre sent in cells grown on propanol, isethionate or taurine. Whole-cell suspens ions of both strains accumulated acetone when oxidizing the non-growth subs trate 2-propanesulfonate. Strain P40 cells also accumulated sulfite under t hese conditions. Stoichiometric measurements with 2-propanesulfonate as sub strate in oxygen electrode experiments indicate that the nonsubstituted alk anesulfonates were degraded by a monooxygenase. When strain P53 grew with n onsubstituted alkanesulfonates as carbon and energy source, cells expressed high amounts of yellow pigments, supporting the proposition that an oxygen ase containing iron sulfur centres or flavins was involved in their degrada tion.