title: Light-dependent transformation of aniline to indole esters by the purple bacterium Rhodobacter sphaeroides OU5.
abstract: In an attempt to understand the aromatic hydrocarbon metabolism by purple bacteria that do not grow at their expense, we earlier reported 2-aminobenzoate transformation by a purple non-sulfur bacterium, Rhodobacter sphaeroides OU5 (Sunayana et al., 2005, J Ind Microbiol Biotech 32:41-45), which is extended in the present study with aniline, a major environmental pollutant. Aniline did not support photo (light anaerobic) or chemo (dark aerobic) heterotrophic growth of Rhodobacter sphaeroides OU5 either as a sole source of carbon or nitrogen. However, light-dependent aniline transformation was observed in the culture supernatants and the products were identified as indole derivatives. The transformation was dependent on a tricarboxylate intermediate, fumarate. Five intermediates of the aniline biotransformation pathway were isolated and identified as indole esters having a mass of 443, 441, 279, 189, and 167 with unstoichiometric total indole yields of 0.16 mM: from 5 mM: of aniline consumed. The pathway proposed based on these intermediates suggest a novel xenobiotic detoxification process in bacteria.
authors.affiliation: Department of Plant Sciences, School of Life Sciences, University of Hyderabad P.O. Central University, Hyderabad, 500 046, India.
authors.forename: Vijay
authors.initials: V
authors.lastname: Shanker
authors.forename: Sunayana Mandala
authors.initials: SM
authors.lastname: Rayabandla
authors.forename: Ranjith Nayak
authors.initials: RN
authors.lastname: Kumavath
authors.forename: Sasikala
authors.initials: S
authors.lastname: Chintalapati
authors.forename: Ramana
authors.initials: R
authors.lastname: Chintalapati
mesh_terms: D000814:Aniline Compounds / Q000378:metabolism*; D001673:Biodegradation, Environmental; D005650:Fumarates / Q000378:metabolism; D007211:Indoles / Q000378:metabolism; D008027:Light; D012242:Rhodobacter sphaeroides / Q000254:growth & development / Q000378:metabolism*; D015262:Xenobiotics / Q000378:metabolism
chemical_list: D000814:Aniline Compounds; D005650:Fumarates; D007211:Indoles; D015262:Xenobiotics; C032005:fumaric acid; C023650:aniline