title: Recruitment of a chromosomally encoded maleylacetate reductase for degradation of 2,4-dichlorophenoxyacetic acid by plasmid pJP4.
abstract: When Pseudomonas aeruginosa PAO1c or P. putida PPO200 or PPO300 carry plasmid pJP4, which encodes enzymes for the degradation of 2,4-dichlorophenoxyacetic acid (TFD) to 2-chloromaleylacetate, cells do not grow on TFD and UV-absorbing material with spectral characteristics of chloromaleylacetate accumulates in the culture medium. Using plasmid pRO1727, we cloned from the chromosome of a nonfluorescent pseudomonad, Pseudomonas sp. strain PKO1, 6- and 0.5-kilobase BamHI DNA fragments which contain the gene for maleylacetate reductase. When carrying either of the recombinant plasmids, pRO1944 or pRO1945, together with pJP4, cells of P. aeruginosa or P. putida were able to utilize TFD as a sole carbon source for growth. A novel polypeptide with an estimated molecular weight of 18,000 was detected in cell extracts of P. aeruginosa carrying either plasmid pRO1944 or plasmid pRO1945. Maleylacetate reductase activity was induced in cells of P. aeruginosa or P. putida carrying plasmid pRO1945, as well as in cells of Pseudomonas strain PKO1, when grown on L-tyrosine, suggesting that the tyrosine catabolic pathway might be the source from which maleylacetate reductase is recruited for the degradation of TFD in pJP4-bearing cells of Pseudomonas sp. strain PKO1.
authors.affiliation: Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor 48109-0620.
authors.forename: J J
authors.initials: JJ
authors.lastname: Kukor
authors.forename: R H
authors.initials: RH
authors.lastname: Olsen
authors.forename: J S
authors.initials: JS
authors.lastname: Siak
mesh_terms: D015084:2,4-Dichlorophenoxyacetic Acid / Q000378:metabolism*; D002712:Chlorides / Q000378:metabolism; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics; D004790:Enzyme Induction / Q000187:drug effects; D005786:Gene Expression Regulation; D005798:Genes, Bacterial; D010088:Oxidoreductases / Q000235:genetics*; D044925:Oxidoreductases Acting on CH-CH Group Donors; D010957:Plasmids; D011549:Pseudomonas / Q000201:enzymology / Q000235:genetics*; D015183:Restriction Mapping; D014443:Tyrosine / Q000494:pharmacology
chemical_list: D002712:Chlorides; D004269:DNA, Bacterial; D015084:2,4-Dichlorophenoxyacetic Acid; D014443:Tyrosine; D010088:Oxidoreductases; D044925:Oxidoreductases Acting on CH-CH Group Donors; C021530:maleylacetate reductase