Reineke W, Jeenes D J, Williams P A, Knackmuss H J
J Bacteriol. 1982 Apr;150(1):195-201. doi: 10.1128/jb.150.1.195-201.1982.
The hybrid pathway for chlorobenzoate metabolism was studied in WR211 and WR216, which were derived from Pseudomonas sp. B13 by acquisition of TOL plasmid pWW0 from Pseudomonas putida mt-2. Chlorobenzoates are utilized readily by these strains when meta cleavage of chlorocatechols is suppressed. When WR211 utilizes 3-chlorobenzoate (3CB), the expression of catechol 2,3-dioxygenase (C23O) and the catabolic activities for chloroaromatics via the ortho pathway coexist as a consequence of inactivation of the meta cleavage activity by 3-chlorocatechol. Utilization of 4-chlorobenzoate (4CB) by WR216 presupposes the suppression of C23O by a spontaneous mutation in the structural gene, so that 4-chlorocatechol is not misrouted into the meta pathway. Such C23O- mutants were also selected when WR211 was grown continuously on 3CB. Our data explain why the phenotypic characters 3CB+ and Mtol+ (m-toluate) are compatible, whereas 4CB+ and Mtol+ are incompatible.
在WR211和WR216中研究了氯苯甲酸酯的混合代谢途径,这两个菌株是由假单胞菌属B13通过从恶臭假单胞菌mt - 2获得TOL质粒pWW0而衍生得到的。当氯儿茶酚的间位裂解受到抑制时,这些菌株能够很容易地利用氯苯甲酸酯。当WR211利用3 - 氯苯甲酸酯(3CB)时,由于3 - 氯儿茶酚使间位裂解活性失活,儿茶酚2,3 - 双加氧酶(C23O)的表达以及通过邻位途径对氯代芳烃的分解代谢活性同时存在。WR216对4 - 氯苯甲酸酯(4CB)的利用预先假定结构基因中的自发突变会抑制C23O,这样4 - 氯儿茶酚就不会误入间位途径。当WR211在3CB上连续生长时,也筛选到了这样的C23O突变体。我们的数据解释了为什么表型特征3CB +和Mtol +(间甲苯酸)是相容的,而4CB +和Mtol +是不相容的。