Degradation of p-chlorotoluene by a mutant of Pseudomonas sp. strain JS6

Journal Article · Wed Feb 01 04:00:00 EST 1989 · Applied and Environmental Microbiology; (USA)

OSTI ID:5025566

Haigler, B E; Spain, J C ^[1]

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1. Air Force Engineering and Services Center, Tyndall Air Force Base, FL (USA)

Pseudomonas sp. strain JS6 grows on chlorobenzene, p-dichlorobenzene, or toluene as a sole source of carbon and energy. It does not grow on p-chlorotoluene (p-CT). Growth on glucose in the presence of p-CT resulted in the accumulation of 4-chloro-2,3- dihydroxy-1-methyl benzene (3-chloro-6- methylcatechol), 4-chloro- 2,3-dihydroxy-1-methyl cyclohexa- 4,6-diene (p-CT dihydrodoil), and 2-methyl-4-carboxy methylenebut-2-en-4-olide (2-methyl dienelactone). Strain JS21, a spontaneous mutant capable of growth on p-CT, was isolated from cultures of strain JS6 after extended exposure to p-CT. In addition to growing on p-CT, JS21 grew on all of the substrates that supported growth of the parent strain, including p-dichlorobenzene, chlorobenzene, benzene, toluene, benzoate, p-hydroxybenzoate, phenol, and ethylbenzene. The pathway for degradation of p-CT by JS21 was investigated by respirometry, isolation of intermediates, and assay of enzymes in cell extracts. p-CT was converted to 3-chloro-6-methylcatechol by dioxygenase and dihydrodiol dehydrogenase enzymes. 3-Chloro-6-methylcatechol underwent ortho ring cleavage catalyzed by a catechol 1,2-dioxygenase to form 2-chloro-5-methyl-cis,cis-muconate, which was converted to 2-methyl dienelactone. A dienelactone hydrolase converted 2-methyl dienelactone to 2-methylmaleylacetic acid. Preliminary results indicate that a change in wild-type induction patterns allows JS21 to grow on p-CT.

• OSTI ID: 5025566
• Journal Information: Applied and Environmental Microbiology; (USA), Journal Name: Applied and Environmental Microbiology; (USA) Vol. 55:2; ISSN 0099-2240; ISSN AEMID
• Country of Publication: United States
• Language: English

Related Subjects

550500* -- Metabolism
59 BASIC BIOLOGICAL SCIENCES
ALKYLATED AROMATICS
AROMATICS
BACTERIA
BENZENE
BIODEGRADATION
BIOLOGICAL PATHWAYS
CHEMICAL REACTIONS
DECOMPOSITION
ENZYMES
GROWTH
HYDROCARBONS
METABOLISM
MICROORGANISMS
MUTANTS
ORGANIC CHLORINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
OXIDOREDUCTASES
OXYGENASES
PSEUDOMONAS
TOLUENE