Mutants of Pseudomonas cepacia G4 defective in catabolism of aromatic compounds and trichloroethylene
Mutants of Pseudomonas cepacia G4 defective in catabolism of aromatic compounds and trichloroethylene
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芳香族化合物和三氯乙烯分解代谢缺陷的洋葱假单胞菌 G4 突变体
DOI：
10.1128/aem.57.7.1935-1941.1991
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发表时间：
1991
影响因子：
4.4
通讯作者：
P. H. Pritchard
中科院分区：
文献类型：
--
作者：
M. Shields;S. Montgomery;S. Cuskey;P. Chapman;P. H. Pritchard
洋葱假单胞菌 G4 拥有一种新的甲苯分解代谢途径，该途径被证明负责三氯乙烯 (TCE) 的降解。该途径涉及甲苯通过邻甲酚转化为 3-甲基儿茶酚。为了确定负责 TCE 降解的甲苯降解酶，对阻断 G4 甲苯原单加氧酶 (TOM) 途径的化学诱导突变体进行了检查。 TOMA-表型突变体在氧化甲苯、邻甲酚、间甲酚和苯酚的能力上均存在缺陷，这表明在野生型中，单一酶负责将这些化合物转化为其羟基化产物（从甲苯转化为3-甲基儿茶酚、从邻甲酚转化为3-甲基儿茶酚，以及从苯酚转化为间甲酚和儿茶酚）。此类突变体不会降解 TCE。另外两个突变体类别的甲苯分解代谢被阻断，TOM B-（缺乏儿茶酚-2,3-双加氧酶）和TOM C-（缺乏2-羟基-6-氧代庚二烯酸水解酶活性）完全能够降解TCE。因此，TCE 降解与甲苯、甲酚和苯酚羟基化的单氧化能力直接相关。
Pseudomonas cepacia G4 possesses a novel pathway of toluene catabolism that is shown to be responsible for the degradation of trichloroethylene (TCE). This pathway involves conversion of toluene via o-cresol to 3-methylcatechol. In order to determine the enzyme of toluene degradation that is responsible for TCE degradation, chemically induced mutants, blocked in the toluene ortho-monooxygenase (TOM) pathway of G4, were examined. Mutants of the phenotypic class designated TOM A- were all defective in their ability to oxidize toluene, o-cresol, m-cresol, and phenol, suggesting that a single enzyme is responsible for conversion of these compounds to their hydroxylated products (3-methylcatechol from toluene, o-cresol, and m-cresol and catechol from phenol) in the wild type. Mutants of this class did not degrade TCE. Two other mutant classes which were blocked in toluene catabolism, TOM B-, which lacked catechol-2,3-dioxygenase, and TOM C-, which lacked 2-hydroxy-6-oxoheptadienoic acid hydrolase activity, were fully capable of TCE degradation. Therefore, TCE degradation is directly associated with the monooxygenation capability responsible for toluene, cresol, and phenol hydroxylation.
影响因子：
2.9
作者：
FOX, BG;BORNEMAN, JG;LIPSCOMB, JD
通讯作者：
LIPSCOMB, JD