Kar A K, Ghosh A S, Chauhan K, Ahamed J, Basu J, Chakrabarti P, Kundu M
Department of Chemistry, Bose Institute, Calcutta, India.
Antimicrob Agents Chemother. 1997 Oct;41(10):2302-4. doi: 10.1128/AAC.41.10.2302.
A beta-lactam-sensitive strain (C152) of Shigella dysenteriae showed two major outer membrane proteins (OMPs) with M(r)s of 43,000 and 38,000, while the clinical isolate M2 lacked the 43,000-Mr OMP, which acted as a channel for beta-lactam antibiotics. Permeability of beta-lactams across the outer membrane (OM) of M2 was lower than that across the OM of C152. Mutants deficient in the 43-kDa OMP could be selected in vitro from strain C152 in the presence of cefoxitin. All beta-lactam-resistant strains were sensitive to imipenem.
一株对β-内酰胺敏感的痢疾志贺氏菌（C152）显示出两种主要的外膜蛋白（OMP），分子量分别为43,000和38,000，而临床分离株M2缺乏分子量为43,000的OMP，该蛋白作为β-内酰胺抗生素的通道。β-内酰胺穿过M2外膜（OM）的通透性低于穿过C152外膜的通透性。在头孢西丁存在的情况下，可从C152菌株体外筛选出缺乏43-kDa OMP的突变体。所有对β-内酰胺耐药的菌株对亚胺培南敏感。
