Substrate specificity of the RND-type multidrug efflux pumps AcrB and AcrD of Escherichia coli is determined predominantly by two large periplasmic loops.

ABSTRACT: AcrAB-TolC is a constitutively expressed, tripartite efflux transporter complex that functions as the primary resistance mechanism to lipophilic drugs, dyes, detergents, and bile acids in Escherichia coli. TolC is an outer membrane channel, and AcrA is an elongated lipoprotein that is hypothesized to span the periplasm and coordinate efflux of such substrates by AcrB and TolC. AcrD is an efflux transporter of E. coli that provides resistance to aminoglycosides as well as to a limited range of amphiphilic agents, such as bile acids, novobiocin, and fusidic acid. AcrB and AcrD belong to the resistance nodulation division superfamily and share a similar topology, which includes a pair of large periplasmic loops containing more than 300 amino acid residues each. We used this knowledge to test

SUBMITTER: Elkins CA 

PROVIDER: S-EPMC135441 | biostudies-literature | 2002 Dec

REPOSITORIES: biostudies-literature