Segregational and structural instability of recombinant plasmid carrying genes for naphthalene degrading pathway.
The stability of recombinant plasmid carrying genes for naphthalene mineralization was determined. A strain of Pseudomonas putida capable of mineralizing naphthalene (Nap+) via salicylate (Sal+) was isolated, and all regulatory and structural genes for the whole pathway were found to be encoded on a 25 kb EcoRI fragment of an approximately 83 kb plasmid present in this strain. The 25 kb EcoRI fragment was cloned into a tetracycline-resistant (TcR) cloning vector pLAFR3 and the recombinant plasmid, pRKJ3 (Nap+, Sal+, TcR), thus obtained was transferred into the plasmid-free strain Pseudomonas putida KT2442 in order to test the stability of the plasmid. Plasmid pRKJ3 was found to be segregationally and/or structurally unstable, depending on the growth conditions. Two types of novel derivative strains having the phenotypes Nap-, Sal+, TcR and Nap-, Sal-, TcR with specific deletions of approximately 2 kb and 18 kb, respectively, were obtained.
Samanta
S K
SK
Institute of Microbial Technology, Chandigarh, India.
Rani
M
M
Jain
R K
RK
D004587:Electrophoresis, Agar Gel; D017353:Gene Deletion; D005798:Genes, Bacterial / Q000235:genetics*; D009281:Naphthalenes / Q000378:metabolism*; D010641:Phenotype; D010957:Plasmids / Q000235:genetics* / Q000378:metabolism; D016958:Pseudomonas putida / Q000235:genetics* / Q000378:metabolism
D009281:Naphthalenes