B. subtilis multidrug resistance ATP-binding cassette (ABC) transporter ATP-binding protein (BmrA), also known as YvcC, is a multidrug ABC transporter that is constitutively expressed in B. subtilis.1 It belongs to the ABC family and shares sequence homology to mammalian P-glycoprotein (P-gp) and LmrA from L. lactis. BmrA is also homologous to HorA, a multidrug ABC transporter from L. brevis, Q8Y3T6 and Q8NXS2, putative transporters from Gram-positive bacteria, and MsbA, a lipid A transporter from E. coli. BmrA transports Hoechst, doxorubicin, and 7-aminoactinomycin D in an ATP-dependent manner. The ATPase mutants BmrAK380A and BmrAK380R are completely devoid of transport activity. Mutations in the intergenic region preceding bmrA incrEAse BmrA mRNA expression and bmrA promoter activity in B. subtilis, which confer resistance to the antibiotic cervimycin C.2 Technical Information Synonyms Multidrug Resistance ABC Transporter ATP-binding/permEAse Protein BmrA Purity 90% estimated by SDS-PAGE Source N-terminal histidine-tagged B. subtilis strain 168 BmrA purified from E. coli Amino Acids Full-length, wild-type sequence MW 64.5 kDa Formulation 50 mM Tris-Cl, pH 8.0, 100 mM NaCl, 0.01