一株对阿米卡星、头孢噻肟和拉莫三嗪耐药的粘质沙雷氏菌“灰色”菌落变体的质粒非依赖性耐药性

Plasmid-independent resistance of 'gray' colony variants of a strain of Serratia marcescens resistant to amikacin, cefotaxime and lamoxactam.

作者信息

Traub W H, Spohr M, Bauer D

出版信息

Chemotherapy. 1983;29(4):265-74. doi: 10.1159/000238208.

Abstract

A multiple-drug-resistant strain of Serratia marcescens (serotype O14:H12; bacteriocin type 18), which was recovered repeatedly from the respiratory tract of an intensive care unit patient, yielded 'gray' colony phenotypic variants which were greater than or equal to four-fold less susceptible to amikacin, cefotaxime, and lamoxactam, but not to netilmicin and N-formimidoyl thienamycin, as compared with 'opaque' (wild-type) colony variants. The 'gray' variants proved phenotypically highly unstable and displayed comparable low virulence for NMRI mice (intraperitoneal route). The 'opaque' and 'gray' variants of this strain carried a nonconjugative, 46-megadalton resistance (R) plasmid, as determined by DNA agarose gel electrophoresis. The R-plasmid-mediated resistance against chloramphenicol, gentamicin, kanamycin, mezlocillin, piperacillin, triple sulfonamides, and cotrimoxazole, as demonstrated with 'curing' experiments. The mechanism of the novel amikacin-beta-lactam antibiotic resistance phenomenon remained undetermined.

摘要

一株粘质沙雷氏菌多重耐药菌株（血清型O14:H12；细菌素类型18），该菌株从一名重症监护病房患者的呼吸道中反复分离得到，产生了“灰色”菌落表型变异体，与“不透明”（野生型）菌落变异体相比，这些变异体对阿米卡星、头孢噻肟和拉莫三嗪的敏感性降低了四倍或更多，但对奈替米星和N-甲酰亚胺基硫霉素不敏感。“灰色”变异体在表型上被证明高度不稳定，并且对NMRI小鼠（腹腔注射途径）显示出相当低的毒力。通过DNA琼脂糖凝胶电泳确定，该菌株的“不透明”和“灰色”变异体携带一个非接合性的46兆道尔顿耐药（R）质粒。通过“消除”实验证明，R质粒介导了对氯霉素、庆大霉素、卡那霉素、美洛西林、哌拉西林、三联磺胺和复方新诺明的耐药性。新型阿米卡星-β-内酰胺抗生素耐药现象的机制仍未确定。