Hayes M V, Orr D C
J Antimicrob Chemother. 1983 Aug;12(2):119-26. doi: 10.1093/jac/12.2.119.
The competition of a new aminothiazolyl cephalosporin, ceftazidime, for the penicillin-binding proteins (PBP's) of Escherichia coli K12, Pseudomonas aeruginosa and Staphylococcus aureus has been studied. Ceftazidime caused filamentation and eventually cell lysis of both E. coli and Ps. aeruginosa at its minimum inhibitory concentration, due to its primary activity against PBP-3. The antibiotic also inhibited PBP's 1 a and 1 bs, the 'essential' cell elongation proteins at higher, therapeutically achievable concentrations and consequently induced rapid lysis of both E. coli and Ps. aeruginosa. In Staph. aureus ceftazidime showed high affinity for PBP-1, -2 and less affinity for PBP-3. The results indicate that in E. coli K12 and Ps. aeruginosa, ceftazidime owes its good antibacterial activity to high affinity for PBP-3, the 'essential' binding protein involved in cell division combined with favourable outer membrane penetration.
研究了新型氨噻唑基头孢菌素头孢他啶对大肠杆菌K12、铜绿假单胞菌和金黄色葡萄球菌青霉素结合蛋白（PBPs）的竞争作用。头孢他啶在其最低抑菌浓度时会导致大肠杆菌和铜绿假单胞菌出现丝状化并最终细胞裂解，这是由于其对PBP-3的主要活性所致。该抗生素在更高的、治疗上可达到的浓度时还会抑制PBP-1a和1bs，即“必需”的细胞伸长蛋白，从而导致大肠杆菌和铜绿假单胞菌快速裂解。在金黄色葡萄球菌中，头孢他啶对PBP-1、-2显示出高亲和力，对PBP-3的亲和力较低。结果表明，在大肠杆菌K12和铜绿假单胞菌中，头孢他啶良好的抗菌活性归因于其对PBP-3的高亲和力，PBP-3是参与细胞分裂的“必需”结合蛋白，同时还具有良好的外膜通透性。
