Savard P, Péloquin L, Sylvestre M
J Bacteriol. 1986 Oct;168(1):81-5. doi: 10.1128/jb.168.1.81-85.1986.
The degradation of 4-chlorobenzoate (4-CBA) by Pseudomonas sp. strain CBS3 is thought to proceed first by the dehalogenation of 4-CBA to 4-hydroxybenzoate (4-HBA), which is then metabolized following the protocatechuate branch of the beta-ketoadipate pathway. The cloning of the 4-CBA dehalogenation system was carried out by constructing a gene bank of Pseudomonas sp. strain CBS3 in Pseudomonas putida. Hybrid plasmid pPSA843 contains a 9.5-kilobase-pair fragment derived from the chromosome of Pseudomonas sp. strain CBS3. This plasmid confers on P. putida the ability to dehalogenate 4-CBA and grow on 4-CBA as the only source of carbon. However, pPSA843 did not complement mutants of P. putida unable to grow on 4-HBA (POB-), showing that the genes involved in the metabolism of 4-HBA were not cloned. Subcloning of Pseudomonas sp. strain CBS3 genes revealed that most of the insert is required for the dehalogenation of 4-CBA, suggesting that more than one gene product is involved in this dehalogenation.
假单胞菌属菌株CBS3对4-氯苯甲酸(4-CBA)的降解被认为首先是通过将4-CBA脱卤生成4-羟基苯甲酸(4-HBA),然后4-HBA沿着β-酮己二酸途径的原儿茶酸分支进行代谢。通过构建假单胞菌属菌株CBS3在恶臭假单胞菌中的基因文库来克隆4-CBA脱卤系统。杂交质粒pPSA843含有一个源自假单胞菌属菌株CBS3染色体的9.5千碱基对片段。该质粒赋予恶臭假单胞菌脱卤4-CBA的能力,并能以4-CBA作为唯一碳源生长。然而,pPSA843不能互补不能在4-HBA上生长的恶臭假单胞菌突变体(POB-),这表明参与4-HBA代谢的基因未被克隆。对假单胞菌属菌株CBS3基因进行亚克隆表明,4-CBA脱卤需要大部分插入片段,这表明该脱卤过程涉及不止一种基因产物。