Stiffler P W, Sweeney H M, Cohen S
J Bacteriol. 1973 Nov;116(2):771-7. doi: 10.1128/jb.116.2.771-777.1973.
Plasmid deoxyribonucleic acid was not detected by centrifugal analysis of lysates of penicillinase-negative strains of Staphylococcus aureus harboring a determinant of methicillin resistance derived from strain Villaluz. When these strains contained a penicillinase plasmid, the plasmid deoxyribonucleic acid of methicillin-resistant and methicillin-susceptible strains was indistinguishable by the methods employed. The results indicate that the genetic determinant for methicillin resistance in the strains examined was not associated with a circular plasmid comparable to those that have been shown to determine resistance to benzylpenicillin, tetracycline, and chloramphenicol in S. aureus.
对携带源自Villaluz菌株的耐甲氧西林决定簇的金黄色葡萄球菌青霉素酶阴性菌株的裂解物进行离心分析,未检测到质粒脱氧核糖核酸。当这些菌株含有青霉素酶质粒时,耐甲氧西林菌株和甲氧西林敏感菌株的质粒脱氧核糖核酸用所采用的方法无法区分。结果表明,所检测菌株中耐甲氧西林的遗传决定簇与一种环状质粒无关,这种环状质粒在金黄色葡萄球菌中已被证明可决定对苄青霉素、四环素和氯霉素的耐药性。