Cloning and characterization of a catechol-degrading gene cluster from 3,4-dichloroaniline degrading bacterium Pseudomonas sp. KB35B.
We recently isolated a bacterium, Pseudomonas sp. KB35B, capable of growth on 3,4-dichloroaniline (DCA) as a sole carbon source. The isolated strain showed a high level of catechol 2,3-dioxygenase (CD-2,3) activity in the presence of 3,4-DCA. In an attempt to elucidate the relationship between biodegradation of 3,4-DCA and CD-2,3 activity, the genes encoding enzymes for the catabolic pathway of catechol were cloned and sequenced from the chromosomal DNA. The sequence analysis of the 10752 bp DNA fragment revealed 12 open reading frames in the order of nahRGTHINLOMKJX. Among the 12 genes, nahHINLOMK genes encode enzymes for the metabolism of catechol to TCA cycle intermediates. The nahR gene is the LysR type transcriptional regulator, and the nahH gene encodes CD-2,3 for meta-cleavages of catechol. 2-Hydroxymuconic semialdehyde hydrolase, 2-oxypent-4-dienoate hydratase, and 4-hydroxy-2-oxovalerate aldolase encoded by nahLMN genes are responsible for the three steps after meta-cleavages of catechol. The current results suggested that Pseudomonas sp. KB35B degrades 3,4-DCA via the meta-cleavage pathway of catechol.
Kim
Young-Mog
YM
Department of Food Science and Technology, Pukyong National University, Busan, 608-737, South Sea Fisheries Research Institute, National Fisheries Research & Development Institute, Yeosu, Jeonnam, 556-823, Korea.
Park
Kunbawui
K
Kim
Won-Chan
WC
Shin
Jae-Ho
JH
Kim
Jang-Eok
JE
Park
Heui-Dong
HD
Rhee
In-Koo
IK
D000814:Aniline Compounds / Q000378:metabolism*; D002396:Catechols / Q000378:metabolism*; D002876:Chromosomes, Bacterial; D004269:DNA, Bacterial / Q000235:genetics; D004798:Enzymes / Q000235:genetics / Q000378:metabolism; D015698:Genomic Library; D005810:Multigene Family; D016366:Open Reading Frames; D010940:Plant Proteins / Q000235:genetics; D010957:Plasmids; D011549:Pseudomonas / Q000235:genetics* / Q000378:metabolism*; D014158:Transcription, Genetic
D000814:Aniline Compounds; D002396:Catechols; D004269:DNA, Bacterial; D004798:Enzymes; D010940:Plant Proteins; C014464:3,4-dichloroaniline; C034221:catechol