Membrane topology of ABC‐type macrolide antibiotic exporter MacB in Escherichia coli

FEBS Letters

Nishino, Kunihiko¹  Kobayashi, Nobuyoshi¹  Yamaguchi, Akihito¹  Hirata, Takahiro¹ 

[1] Department of Cell Membrane Biology, Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan

关键词: ABC transporter;    Membrane topology;    Site-directed mutagenesis;    Cysteine modification;    ABC;    ATP binding cassette;    NEM;    N-ethyl maleimide;    AMS;    4-acetoamide-4′-maleimidylstilbene-2;    2′-disulfonic acid;    NBD;    nucleotide binding domain;    TM;    transmembrane;   

DOI  :  10.1016/S0014-5793(03)00579-9

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

MacB is an ABC-type membrane protein that exports only macrolide compounds containing 14- and 15-membered lactones, cooperating with a membrane fusion protein, MacA, and a multifunctional outer membrane channel, TolC. We determined the membrane topology of MacB by means of site-specific competitive chemical modification of single cysteine mutants. As a result, it was revealed that MacB is composed of four transmembrane (TM) segments with a cytoplasmic N-terminal nucleotide binding domain of about 270 amino acid residues and a periplasmic large hydrophilic polypeptide between TM segments 1 and 2 of about 200 amino acid residues.

【 授权许可】

Unknown