Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2013 Aug 1;500(7460):102-6.
doi: 10.1038/nature12300. Epub 2013 Jun 30.

Structural basis for the inhibition of bacterial multidrug exporters

Affiliations

Structural basis for the inhibition of bacterial multidrug exporters

Ryosuke Nakashima et al. Nature. .

Abstract

The multidrug efflux transporter AcrB and its homologues are important in the multidrug resistance of Gram-negative pathogens. However, despite efforts to develop efflux inhibitors, clinically useful inhibitors are not available at present. Pyridopyrimidine derivatives are AcrB- and MexB-specific inhibitors that do not inhibit MexY; MexB and MexY are principal multidrug exporters in Pseudomonas aeruginosa. We have previously determined the crystal structure of AcrB in the absence and presence of antibiotics. Drugs were shown to be exported by a functionally rotating mechanism through tandem proximal and distal multisite drug-binding pockets. Here we describe the first inhibitor-bound structures of AcrB and MexB, in which these proteins are bound by a pyridopyrimidine derivative. The pyridopyrimidine derivative binds tightly to a narrow pit composed of a phenylalanine cluster located in the distal pocket and sterically hinders the functional rotation. This pit is a hydrophobic trap that branches off from the substrate-translocation channel. Phe 178 is located at the edge of this trap in AcrB and MexB and contributes to the tight binding of the inhibitor molecule through a π-π interaction with the pyridopyrimidine ring. The voluminous side chain of Trp 177 located at the corresponding position in MexY prevents inhibitor binding. The structure of the hydrophobic trap described in this study will contribute to the development of universal inhibitors of MexB and MexY in P. aeruginosa.

PubMed Disclaimer

Similar articles

Cited by

References

    1. J Am Chem Soc. 2011 Jul 20;133(28):10704-7 - PubMed
    1. Nature. 2011 Nov 27;480(7378):565-9 - PubMed
    1. J Biol Chem. 2004 Jul 30;279(31):32116-24 - PubMed
    1. J Bacteriol. 2005 Oct;187(19):6804-15 - PubMed
    1. Science. 1997 Sep 5;277(5331):1453-62 - PubMed

Publication types

MeSH terms