Mechanism of recognition of compounds of diverse structures by the multidrug efflux pump AcrB of Escherichia coli
Mechanism of recognition of compounds of diverse structures by the multidrug efflux pump AcrB of Escherichia coli
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DOI：
10.1073/pnas.1001460107
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发表时间：
2010-04-13
影响因子：
11.1
通讯作者：
Nikaido, Hiroshi
中科院分区：
文献类型：
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作者：
Takatsuka, Yumiko;Chen, Cheng;Nikaido, Hiroshi
大肠杆菌的AcrB三聚体多药物外排转运蛋白泵出非常广谱的化合物。虽然米诺环素和多柔比星已共结晶内的大结合口袋中的周质结构域的结合原体，没有什么是已知的许多其他配体的这种蛋白质的结合。我们使用计算机对接来评估约30种化合物与结合原聚体的相互作用，发现其中许多化合物被预测结合到口袋一端的狭窄凹槽，而其他一些化合物则更喜欢结合到另一端的宽洞穴。竞争分析使用头孢硝肟流出和共价标记的Phe 615 Cys突变体AcrB与荧光素-5-马来酰亚胺表明，假定的沟粘合剂相互竞争，但洞穴粘合剂不竞争对沟粘合剂，虽然测试的化合物的数量是有限的。这些结果至少给了我们一个假设，有待于将来通过更多的生化和遗传实验来检验。
The AcrB trimeric multidrug efflux transporter of Escherichia coli pumps out a very wide spectrum of compounds. Although minocycline and doxorubicin have been cocrystallized within the large binding pocket in the periplasmic domain of the binding protomer, nothing is known about the binding of many other ligands to this protein. We used computer docking to evaluate the interaction of about 30 compounds with the binding protomer and found that many of them are predicted to bind to a narrow groove at one end of the pocket whereas some others prefer to bind to a wide cave at the other end. Competition assays using nitrocefin efflux and covalent labeling of Phe615Cys mutant AcrB with fluorescein-5-maleimide showed that presumed groove-binders competed against each other, but cave-binders did not compete against groove-binders, although the number of compounds tested was limited. These results give us at least a hypothesis to be tested by more biochemical and genetic experiments in the future.