title: Isolation and characterization of a rhodococcus species strain able to grow on ortho- and para-xylene.
abstract: Rhodococcus sp. strain YU6 was isolated from soil for the ability to grow on o-xylene as the sole carbon and energy source. Unlike most other o-xylene-degrading bacteria, YU6 is able to grow on p-xylene. Numerous growth substrate range experiments, in addition to the ring-cleavage enzyme assay data, suggest that YU6 initially metabolizes o- and p-xylene by direct aromatic ring oxidation. This leads to the formation of dimethylcatechols, which was further degraded largely through meta-cleavage pathway. The gene encoding meta-cleavage dioxygenase enzyme was PCR cloned from genomic YU6 DNA using previously known gene sequence data from the o-xylene-degrading Rhodococcus sp. strain DK17. Subsequent sequencing of the 918-bp PCR product revealed a 98% identity to the gene, encoding methylcatechol 2,3-dioxygenase from DK17. PFGE analysis followed by Southern hybridization with the catechol 2,3-dioxygenase gene demonstrated that the gene is located on an approximately 560-kb megaplasmid, designated pJYJ1.
authors.affiliation: Department of Biology, Yonsei University, Seoul 120-749, Republic of Korea.
authors.forename: Jung Yeon
authors.initials: JY
authors.lastname: Jang
authors.forename: Dockyu
authors.initials: D
authors.lastname: Kim
authors.forename: Hyun Won
authors.initials: HW
authors.lastname: Bae
authors.forename: Ki Young
authors.initials: KY
authors.lastname: Choi
authors.forename: Jong-Chan
authors.initials: JC
authors.lastname: Chae
authors.forename: Gerben J
authors.initials: GJ
authors.lastname: Zylstra
authors.forename: Young Min
authors.initials: YM
authors.lastname: Kim
authors.forename: Eungbin
authors.initials: E
authors.lastname: Kim
mesh_terms: D015139:Blotting, Southern; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D049308:Dioxygenases / Q000096:biosynthesis / Q000235:genetics; D016521:Electrophoresis, Gel, Pulsed-Field; D004790:Enzyme Induction; D016680:Genome, Bacterial; D016133:Polymerase Chain Reaction; D012240:Rhodococcus / Q000201:enzymology / Q000235:genetics / Q000254:growth & development* / Q000302:isolation & purification*; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology; D014992:Xylenes / Q000378:metabolism*
chemical_list: D004269:DNA, Bacterial; D014992:Xylenes; C031286:4-xylene; D049308:Dioxygenases; C026114:2-xylene