Matsuhashi M, Song M D, Ishino F, Wachi M, Doi M, Inoue M, Ubukata K, Yamashita N, Konno M
J Bacteriol. 1986 Sep;167(3):975-80. doi: 10.1128/jb.167.3.975-980.1986.
A novel penicillin-binding protein, PBP-2' (Mr about 75,000), is known to be induced in excessively large amount by most beta-lactam compounds in cells of a clinically isolated strain of Staphylococcus aureus, TK784, that is highly resistant to beta-lactams and also most other antibiotics. This protein has very low affinities to most beta-lactam compounds and has been supposed to be the cause of the resistance of the cells to beta-lactams. A 14-kilobase DNA fragment was isolated from the cells that carried the gene encoding this penicillin-binding protein and also a genetically linked marker that is responsible for the resistance to tobramycin. This DNA was cloned on plasmid pACYC184 and was shown to cause both production of PBP-2' and resistance to tobramycin in Escherichia coli cells. However, the formation of PBP-2' in E. coli was only moderate and was independent of normal inducer beta-lactams. The PBP-2' formed in the E. coli cells showed slow kinetics of binding to beta-lactams similar to that of PBP-2' formed in the original S. aureus cells and gave a similar pattern of peptides to the latter when digested with the proteolytic V8 enzyme of S. aureus.
一种新型青霉素结合蛋白，PBP - 2'（分子量约75,000），已知在临床分离的金黄色葡萄球菌TK784菌株的细胞中，会被大多数β-内酰胺类化合物大量诱导产生。该菌株对β-内酰胺类以及大多数其他抗生素具有高度抗性。这种蛋白对大多数β-内酰胺类化合物的亲和力非常低，被认为是细胞对β-内酰胺类产生抗性的原因。从携带编码这种青霉素结合蛋白基因以及与对妥布霉素抗性相关的遗传连锁标记的细胞中分离出一个14千碱基的DNA片段。该DNA被克隆到质粒pACYC184上，并显示能在大肠杆菌细胞中同时导致PBP - 2'的产生和对妥布霉素的抗性。然而，大肠杆菌中PBP - 2'的形成程度仅为中等，且与正常诱导剂β-内酰胺类无关。在大肠杆菌细胞中形成的PBP - 2'与在原始金黄色葡萄球菌细胞中形成的PBP - 2'相比，显示出与β-内酰胺类结合的动力学较慢，并且在用金黄色葡萄球菌的蛋白水解酶V8消化时，产生的肽图谱与后者相似。
