Regioselective oxidation of xylene isomers by Rhodococcus sp. strain DK17.
Rhodococcus sp. strain DK17 is able to utilize a variety of monocyclic aromatic hydrocarbons, including benzene, phenol, toluene, and o-xylene, as growth substrates. Although DK17 is unable to grow on m- and p-xylene, this strain could transform these two xylene isomers to some extent after induction by o-xylene. The major accumulating compounds formed during the degradation of m- and p-xylene by DK17 were isolated by high-pressure liquid chromatography and identified by gas chromatography-mass spectrometric and (1)H nuclear magnetic resonance spectral techniques. Both xylene isomers were transformed to dihydroxylated compounds by what must be two successive hydroxylation events: m-xylene was converted to 2,4-dimethylresorcinol and p-xylene was converted to 2,5-dimethylhydroquinone. The rigorous structural identification of 2,4-dimethylresorcinol and 2,5-dimethylhydroquinone demonstrates that DK17 can perform distinct regioselective hydroxylations depending on the position of the substituent groups on the aromatic ring.
Kim
Dockyu
D
Department of Biology and Institute of Life Science and Biotechnology, Yonsei University, Seoul 120-749, South Korea.
Kim
Young-Soo
YS
Jung
Jae Woo
JW
Zylstra
Gerben J
GJ
Kim
Young Min
YM
Kim
Seong-Ki
SK
Kim
Eungbin
E
D006900:Hydroxylation; D010084:Oxidation-Reduction; D010105:Oxygenases / Q000378:metabolism; D012240:Rhodococcus / Q000201:enzymology* / Q000254:growth & development; D013379:Substrate Specificity; D014050:Toluene / Q000737:chemistry / Q000378:metabolism; D014992:Xylenes / Q000737:chemistry / Q000378:metabolism*
D014992:Xylenes; D014050:Toluene; D010105:Oxygenases