Two-component bacterial multidrug transporter, EbrAB: Mutations making each component solely functional.

Takashi Kikukawa; Toshifumi Nara; Tsunehisa Araiso; Seiji Miyauchi; Naoki Kamo

doi:10.1016/j.bbamem.2006.04.004

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PubMed · 16750162

Two-component bacterial multidrug transporter, EbrAB: Mutations making each component solely functional.

Takashi Kikukawa·Toshifumi Nara·Tsunehisa Araiso·Seiji Miyauchi·Naoki Kamo

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Abstract

EbrAB 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.

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Amino Acid Sequence Bacillus subtilis Base Sequence Carrier Proteins DNA Primers Electrophoresis, Polyacrylamide Gel Escherichia coli Ethidium Microbial Sensitivity Tests Molecular Sequence Data Mutation Pharmaceutical Preparations Plasmids Sequence Homology, Amino Acid Journal Article Research Support, Non-U.S. Gov't

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Takashi Kikukawa, Toshifumi Nara, Tsunehisa Araiso, Seiji Miyauchi, Naoki Kamo. 2006-04-21. Two-component bacterial multidrug transporter, EbrAB: Mutations making each component solely functional.. https://doi.org/10.1016/j.bbamem.2006.04.004

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