期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1975
卷号：72
期号：9
页码：3647-3651
DOI：10.1073/pnas.72.9.3647
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Conditions optimal for the transformation of Pseudomonas putida and E. coli with a drug-resistance factor (RP 1) DNA, which specifies resistance to carbenicillin, tetracycline, kanamycin, and neomycin, are described. The transformants retain all the fertility, incompatibility, and drug-resistance characteristics present in the parent. Covalently-closed circular molecules of almost identical contour lengths have been isolated from the parent and the transformants. The frequency of transformation is drastically reduced by treatment of RP 1 DNA with DNase and by denaturation or sonication. Shearing of RP 1 DNA in vitro and their subsequent introduction in P. putida cells, by transformation, produces transformants that exhibit a wide range of drug-resistant phenotypes, including those which are resistant to neomycin but sensitive to kanamycin. Isolation of such neomycin-resistant but kanamycin-sensitive transformants indicates that there might be two separate mechanisms specified by RP 1 for resistance to the two antibiotics.
