AcrB drug-binding pocket substitution confers clinically relevant resistance and altered substrate specificity
Research output: Contribution to journal › Article › peer-review
Standard
AcrB drug-binding pocket substitution confers clinically relevant resistance and altered substrate specificity. / Blair, Jessica M. A.; Bavro, Vassiliy N.; Ricci, Vito; Modi, Niraj; Cacciotto, Pierpaolo; Kleinekathӧfer, Ulrich; Ruggerone, Paolo; Vargiu, Attilio V.; Baylay, Alison J.; Smith, Helen E.; Brandon, Yvonne; Galloway, David; Piddock, Laura J. V.
In: National Academy of Sciences. Proceedings, Vol. 112, No. 11, 17.03.2015, p. 3511-3516.Research output: Contribution to journal › Article › peer-review
Harvard
APA
Vancouver
Author
Bibtex
}
RIS
TY - JOUR
T1 - AcrB drug-binding pocket substitution confers clinically relevant resistance and altered substrate specificity
AU - Blair, Jessica M. A.
AU - Bavro, Vassiliy N.
AU - Ricci, Vito
AU - Modi, Niraj
AU - Cacciotto, Pierpaolo
AU - Kleinekathӧfer, Ulrich
AU - Ruggerone, Paolo
AU - Vargiu, Attilio V.
AU - Baylay, Alison J.
AU - Smith, Helen E.
AU - Brandon, Yvonne
AU - Galloway, David
AU - Piddock, Laura J. V.
PY - 2015/3/17
Y1 - 2015/3/17
N2 - The incidence of multidrug-resistant bacterial infections is increasing globally and the need to understand the underlying mechanisms is paramount to discover new therapeutics. The efflux pumps of Gram-negative bacteria have a broad substrate range and transport antibiotics out of the bacterium, conferring intrinsic multidrug resistance (MDR). The genomes of pre- and posttherapy MDR clinical isolates of Salmonella Typhimurium from a patient that failed antibacterial therapy and died were sequenced. In the posttherapy isolate we identified a novel G288D substitution in AcrB, the resistance-nodulation division transporter in the AcrAB-TolC tripartite MDR efflux pump system. Computational structural analysis suggested that G288D in AcrB heavily affects the structure, dynamics, and hydration properties of the distal binding pocket altering specificity for antibacterial drugs. Consistent with this hypothesis, recreation of the mutation in standard Escherichia coli and Salmonella strains showed that G288D AcrB altered substrate specificity, conferring decreased susceptibility to the fluoroquinolone antibiotic ciprofloxacin by increased efflux. At the same time, the substitution increased susceptibility to other drugs by decreased efflux. Information about drug transport is vital for the discovery of new antibacterials; the finding that one amino acid change can cause resistance to some drugs, while conferring increased susceptibility to others, could provide a basis for new drug development and treatment strategies.
AB - The incidence of multidrug-resistant bacterial infections is increasing globally and the need to understand the underlying mechanisms is paramount to discover new therapeutics. The efflux pumps of Gram-negative bacteria have a broad substrate range and transport antibiotics out of the bacterium, conferring intrinsic multidrug resistance (MDR). The genomes of pre- and posttherapy MDR clinical isolates of Salmonella Typhimurium from a patient that failed antibacterial therapy and died were sequenced. In the posttherapy isolate we identified a novel G288D substitution in AcrB, the resistance-nodulation division transporter in the AcrAB-TolC tripartite MDR efflux pump system. Computational structural analysis suggested that G288D in AcrB heavily affects the structure, dynamics, and hydration properties of the distal binding pocket altering specificity for antibacterial drugs. Consistent with this hypothesis, recreation of the mutation in standard Escherichia coli and Salmonella strains showed that G288D AcrB altered substrate specificity, conferring decreased susceptibility to the fluoroquinolone antibiotic ciprofloxacin by increased efflux. At the same time, the substitution increased susceptibility to other drugs by decreased efflux. Information about drug transport is vital for the discovery of new antibacterials; the finding that one amino acid change can cause resistance to some drugs, while conferring increased susceptibility to others, could provide a basis for new drug development and treatment strategies.
KW - AcrB
KW - antimicrobial resistance
KW - efflux
KW - whole genome sequencing
U2 - 10.1073/pnas.1419939112
DO - 10.1073/pnas.1419939112
M3 - Article
C2 - 25737552
VL - 112
SP - 3511
EP - 3516
JO - Proceedings of the National Academy of Sciences
JF - Proceedings of the National Academy of Sciences
SN - 1091-6490
IS - 11
ER -