Altered expression of oligopeptide-binding protein (OppA) and aminoglycoside resistance in laboratory and clinical Escherichia coli strains
Altered expression of oligopeptide-binding protein (OppA) and aminoglycoside resistance in laboratory and clinical Escherichia coli strains
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DOI：
10.1099/0022-1317-49-5-409
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发表时间：
2000-05-01
影响因子：
3
通讯作者：
Costa, SOP
中科院分区：
文献类型：
--
作者：
Acosta, MBR;Ferreira, RCC;Costa, SOP
寡肽结合蛋白（Oligopeptide-binding protein，OppA）是肠道细菌主要的寡肽转运系统的周质组分。大肠杆菌K-12对氨基糖苷类抗生素的摄取受OppA的影响。在56株K-12氨基糖苷类耐药突变株中，有40株（82%）OppA水平降低或检测不到。与其亲本菌株相比。此外，9（36%）的25个氨基糖苷类耐药大肠杆菌临床分离株表达减少或检测不到水平的OppA。在来自患者的氨基糖苷类敏感性大肠杆菌菌株中未观察到OppA表达降低。大肠杆菌K-12的56个氨基糖苷类耐药突变体中有23个（42%）和25个临床分离株的sis（24%）也缺乏鸟氨酸或精氨酸脱羧酶或两者的表达，这些缺陷可能通过减少多胺合成而对OppA表达产生负面影响。这些结果支持OppA表达减少与大肠杆菌菌株中的氨基糖苷类耐药性相关的观点。
Oligopeptide-binding protein (OppA) is the periplasmic component of the major oligopeptide transport system of enteric bacteria. Genetic and biochemical evidence suggests that OppA plays a role in the uptake of aminoglycoside antibiotics in Escherichia coli K-12, Forty-sis (82%) of 56 aminoglycoside-resistant mutants of E, coli K-12 selected in vitro had reduced or undetectable OppA levels? as compared with their parent strain. Moreover, nine (36%) of 25 aminoglycoside-resistant clinical isolates of E, coli expressed reduced or undetectable levels of OppA. No decrease in OppA expression was observed among aminoglycoside-sensitive E, coli strains from patients. Twenty-three (42%) of 56 aminoglycoside-resistant mutants of E, coli K-12 and sis (24%) of 25 clinical isolates also were deficient for expression of ornithine or arginine decarboxylases, or both, and these deficiencies might negatively affect OppA expression by reducing polyamine synthesis. These results support the view that reduced OppA expression is associated with aminoglycoside resistance in E, coli strains.