Studying subunit-subunit interactions in a bacterial ABC transporterby in vitro assembly.
The thermostable arginine ABC transporter of Geobacillus stearothermophilus consists of a solute binding protein, ArtJ; a transmembrane subunit, ArtM; and a nucleotide-binding subunit, ArtP. An ArtM/His(6)-ArtP complex was functionally assembled from separately purified subunits as demonstrated by assaying stimulation of its ATPase activity by arginine-loaded ArtJ in proteoliposomes. Studying in vitro assembly with variants carrying mutations in the conserved Q loop and/or the EAA loop of ArtP and ArtM, respectively, confirmed the predicted roles of both motifs in intersubunit signaling and physical interaction, respectively. In vitro assembly is considered a useful tool for investigating assembly defects of ABC transporters caused by mutations.
Institut für Biologie, Physiologie der Mikroorganismen, Humboldt Universität zu Berlin, Chausseestr. 117, D-10115 Berlin, Germany.
Viola
V
Eckey
Heidi
H
Landmesser
Erwin
E
Schneider
D018528:ATP-Binding Cassette Transporters / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D000251:Adenosine Triphosphatases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D020816:Amino Acid Motifs; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli; D001411:Geobacillus stearothermophilus / Q000201:enzymology* / Q000235:genetics; D008081:Liposomes / Q000737:chemistry* / Q000378:metabolism; D009154:Mutation; D021122:Protein Subunits / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
D018528:ATP-Binding Cassette Transporters; D001426:Bacterial Proteins; D008081:Liposomes; D021122:Protein Subunits; D011994:Recombinant Proteins; D000251:Adenosine Triphosphatases