Nishino K, Yamaguchi A
Department of Cell Membrane Biology, Institute of Scientific and Industrial Research, Osaka University, Ibaraki, Osaka 567-0047, Japan.
J Bacteriol. 2001 Oct;183(20):5803-12. doi: 10.1128/JB.183.20.5803-5812.2001.
The complete sequencing of bacterial genomes has revealed a large number of drug transporter genes. In Escherichia coli, there are 37 open reading frames (ORFs) assumed to be drug transporter genes on the basis of sequence similarities, although the transport capabilities of most of them have not been established yet. We cloned all 37 putative drug transporter genes in E. coli and investigated their drug resistance phenotypes using an E. coli drug-sensitive mutant as a host. E. coli cells transformed with a plasmid carrying one of 20 ORFs, i.e., fsr, mdfA, yceE, yceL, bcr, emrKY, emrAB, emrD, yidY, yjiO, ydhE, acrAB, cusA (formerly ybdE), yegMNO, acrD, acrEF, yhiUV, emrE, ydgFE, and ybjYZ, exhibited increased resistance to some of the 26 representative antimicrobial agents and chemical compounds tested in this study. Of these 20 ORFs, cusA, yegMNO, ydgFE, yceE, yceL, yidY, and ybjYZ are novel drug resistance genes. The fsr, bcr, yjiO, ydhE, acrD, and yhiUV genes gave broader resistance spectra than previously reported.
细菌基因组的全序列测定揭示了大量的药物转运蛋白基因。在大肠杆菌中，基于序列相似性推测有37个开放阅读框（ORF）为药物转运蛋白基因，尽管其中大多数的转运能力尚未确定。我们克隆了大肠杆菌中的所有37个假定的药物转运蛋白基因，并以对药物敏感的大肠杆菌突变体作为宿主研究了它们的耐药表型。用携带20个ORF之一（即fsr、mdfA、yceE、yceL、bcr、emrKY、emrAB、emrD、yidY、yjiO、ydhE、acrAB、cusA（原ybdE）、yegMNO、acrD、acrEF、yhiUV、emrE、ydgFE和ybjYZ）的质粒转化的大肠杆菌细胞，对本研究中测试的26种代表性抗菌剂和化合物中的一些表现出耐药性增加。在这20个ORF中，cusA、yegMNO、ydgFE、yceE、yceL、yidY和ybjYZ是新的耐药基因。fsr、bcr、yjiO、ydhE、acrD和yhiUV基因的耐药谱比以前报道的更宽。
