Site-directed mutagenesis reveals putative substrate binding residues in the Escherichia coli RND efflux pump AcrB

J Bacteriol. 2008 Dec;190(24):8225-9. doi: 10.1128/JB.00912-08. Epub 2008 Oct 10.

Abstract

The Escherichia coli multidrug efflux pump protein AcrB has recently been cocrystallized with various substrates, suggesting that there is a phenylalanine-rich binding site around F178 and F615. We found that F610A was the point mutation that had the most significant impact on substrate MICs, while other targeted mutations, including conversion of phenylalanines 136, 178, 615, 617, and 628 to alanine, had smaller and more variable effects.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Binding Sites
  • Drug Resistance, Multiple, Bacterial / genetics
  • Escherichia coli / drug effects
  • Escherichia coli / genetics*
  • Escherichia coli / metabolism
  • Escherichia coli Proteins / genetics
  • Escherichia coli Proteins / metabolism*
  • Microbial Sensitivity Tests
  • Models, Molecular
  • Multidrug Resistance-Associated Proteins / genetics
  • Multidrug Resistance-Associated Proteins / metabolism*
  • Mutagenesis, Site-Directed
  • Phenylalanine / genetics
  • Point Mutation

Substances

  • AcrB protein, E coli
  • Anti-Bacterial Agents
  • Escherichia coli Proteins
  • Multidrug Resistance-Associated Proteins
  • Phenylalanine