Inducible, but not constitutive, resistance of gonococci to hydrophobic agents due to the MtrC-MtrD-MtrE efflux pump requires TonB-ExbB-ExbD proteins.
The MtrC-MtrD-MtrE efflux pump possessed by Neisseria gonorrhoeae is very similar to the MexA-MexB-OprM efflux pump of Pseudomonas aeruginosa. Because the antimicrobial resistance property afforded by the MexA-MexB-OprM efflux pump also requires the TonB protein, we asked whether a similar requirement exists for the gonococcal efflux pump. Unlike earlier studies with P. aeruginosa, we found that constitutive levels of gonococcal resistance to hydrophobic antimicrobial agents (i.e., Triton X-100 [TX-100]) did not require the TonB, ExbB, or ExbD protein. However, inducible levels of TX-100 resistance in gonococci had an absolute requirement for the TonB-ExbB-ExbD system, suggesting that such resistance in gonococci has an energy requirement above and beyond that required for constitutive pump activity.
Rouquette-Loughlin
Corinne
C
Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, Georgia 30322, USA.
Stojiljkovic
Igor
I
Hrobowski
Tara
T
Balthazar
Jacqueline T
JT
Shafer
William M
WM
D001425:Bacterial Outer Membrane Proteins / Q000378:metabolism; D001426:Bacterial Proteins / Q000378:metabolism; D001692:Biological Transport / Q000187:drug effects; D002352:Carrier Proteins / Q000378:metabolism; D004347:Drug Interactions; D024881:Drug Resistance, Bacterial / Q000502:physiology*; D029968:Escherichia coli Proteins / Q000378:metabolism; D057927:Hydrophobic and Hydrophilic Interactions; D007501:Iron / Q000494:pharmacology; D008074:Lipoproteins / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D026901:Membrane Transport Proteins; D009344:Neisseria gonorrhoeae / Q000187:drug effects* / Q000378:metabolism; D017830:Octoxynol / Q000494:pharmacology*; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000378:metabolism; D013501:Surface-Active Agents / Q000494:pharmacology*
D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; C052874:ExbB protein, E coli; D008074:Lipoproteins; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; C094589:MtrC protein, Neisseria gonorrhoeae; C107795:MtrD protein, Neisseria gonorrhoeae; C107796:MtrE protein, Neisseria gonorrhoeae; D013501:Surface-Active Agents; C057616:tonB protein, Bacteria; C489181:tonB protein, E coli; C060790:exbD protein, E coli; D017830:Octoxynol; D007501:Iron