Neuwirth C, Siébor E, Duez J M, Péchinot A, Kazmierczak A
Laboratoire de Bactériologie, Hôpital Universitaire du Bocage, Dijon, France.
J Antimicrob Chemother. 1995 Aug;36(2):335-42. doi: 10.1093/jac/36.2.335.
Two strains of Proteus mirabilis, IpR1 and IpR2, resistant to both imipenem and mecillinam, but susceptible to other beta-lactams were isolated from blood cultures of patients who had been treated with imipenem. Strain IpR1 was isolated in the same sample as a P. mirabilis IpS1 which was susceptible to imipenem and mecillinam. Strains IpR1 and IpR2 did not produce a beta-lactamase and their outer membrane protein profiles were similar to those of IpS1 and P. mirabilis ATCC 29906. Electrophoretic profiles of penicillin-binding proteins (PBPs) showed a decrease in PBP 1A of strains IpR1 and IpR2 compared with IpS1 and ATCC 29906. Competition experiments revealed a decrease in affinity of PBP 2 for imipenem from strain IpR1. These findings suggest that imipenem resistance in P. mirabilis might result from altered PBPs, as reported for Acinetobacter baumanii and Pseudomonas aeruginosa.
从接受亚胺培南治疗的患者血培养物中分离出两株奇异变形杆菌，IpR1和IpR2，它们对亚胺培南和美西林耐药，但对其他β-内酰胺类药物敏感。菌株IpR1与一株对亚胺培南和美西林敏感的奇异变形杆菌IpS1在同一样本中分离得到。菌株IpR1和IpR2不产生β-内酰胺酶，其外膜蛋白图谱与IpS1和奇异变形杆菌ATCC 29906的相似。青霉素结合蛋白（PBPs）的电泳图谱显示，与IpS1和ATCC 29906相比，菌株IpR1和IpR2的PBP 1A减少。竞争实验表明，菌株IpR1中PBP 2对亚胺培南的亲和力降低。这些发现表明，奇异变形杆菌对亚胺培南的耐药性可能是由PBPs改变引起的，如鲍曼不动杆菌和铜绿假单胞菌的报道。
