2024-03-29T09:59:57Zhttps://eprints.lib.hokudai.ac.jp/dspace-oai/requestoai:eprints.lib.hokudai.ac.jp:2115/145842022-11-17T02:08:08Zhdl_2115_20074hdl_2115_161Two-component bacterial multidrug transporter, EbrAB: Mutations making each component solely functionalKikukawa, TakashiNara, ToshifumiAraiso, TsunehisaMiyauchi, SeijiKamo, NaokiEbrABEmrESmrIon-coupled transporterMultidrug resistance464EbrAB in Bacillus subtilis belongs to a novel small multidrug resistance (SMR) family of multidrug efflux pumps. EmrE in Escherichia coli, a representative of SMR, functions as a homo-oligomer in the membrane. On the other hand, EbrAB requires a hetero-oligomeric configuration consisting of two polypeptides, EbrA and EbrB. Although both polypeptides have a high sequence similarity, expression of either single polypeptide does not confer the multidrug-resistance. We performed mutation studies on EbrA and B to determine why EbrAB requires the hetero-oligomerization. Mutants of EbrA and B lacking both the hydrophilic loops and the C-terminus regions conferred the multidrug-resistance solely by each protein. This suggests that the hydrophilic loops and the C-terminus regions constrain them to their respective conformations upon the formation of the functional hetero-oligomer.Elsevier B.V.Journal Articleapplication/pdfhttp://hdl.handle.net/2115/14584https://eprints.lib.hokudai.ac.jp/dspace/bitstream/2115/14584/1/BBAB.pdf0005-2736Biochimica et Biophysica Acta (BBA) - Biomembranes175856736792006-05enginfo:pmid/16750162info:doi/10.1016/j.bbamem.2006.04.004author