Characterization of ceftazidime resistance mechanisms in clinical isolates of burkholderia pseudomallei from Australia

Derek S Sarovich; Erin P Price; A T von Schulze; J M Cook; M Mayo; L M Watson; L Richardson; M L Seymour; A Tuanyok; D M Engelthaler; T Pearson; S J Peacock; B J Currie; P Keim; D M Wagner

doi:10.1371/journal.pone.0030789

Back

Characterization of ceftazidime resistance mechanisms in clinical isolates of burkholderia pseudomallei from Australia

Journal article

Open access

Peer reviewed

Characterization of ceftazidime resistance mechanisms in clinical isolates of burkholderia pseudomallei from Australia

Derek S Sarovich, Erin P Price, A T von Schulze, J M Cook, M Mayo, L M Watson, L Richardson, M L Seymour, A Tuanyok, D M Engelthaler, …

PLoS One, Vol.7(2), e30789

2012

DOI: https://doi.org/10.1371/journal.pone.0030789

Files and links (2)

pdf

PDF - Published Version (Open Access)116.99 kBDownload View

Published VersionPDF - Published Version (Open Access)CC BY V4.0, Open Access

url

https://doi.org/10.1371/journal.pone.0030789View

Published Version

Abstract

Burkholderia pseudomallei is a Gram-negative bacterium that causes the serious human disease, melioidosis. There is no vaccine against melioidosis and it can be fatal if not treated with a specific antibiotic regimen, which typically includes the third-generation cephalosporin, ceftazidime (CAZ). There have been several resistance mechanisms described for B. pseudomallei, of which the best described are amino acid changes that alter substrate specificity in the highly conserved class A β-lactamase, PenA. In the current study, we sequenced penA from isolates sequentially derived from two melioidosis patients with wild-type (1.5 μg/mL) and, subsequently, resistant (16 or ≥256 μg/mL) CAZ phenotypes. We identified two single-nucleotide polymorphisms (SNPs) that directly increased CAZ hydrolysis. One SNP caused an amino acid substitution (C69Y) near the active site of PenA, whereas a second novel SNP was found within the penA promoter region. In both instances, the CAZ resistance phenotype corresponded directly with the SNP genotype. Interestingly, these SNPs appeared after infection and under selection from CAZ chemotherapy. Through heterologous cloning and expression, and subsequent allelic exchange in the native bacterium, we confirmed the role of penA in generating both low-level and high-level CAZ resistance in these clinical isolates. Similar to previous studies, the amino acid substitution altered substrate specificity to other β-lactams, suggesting a potential fitness cost associated with this mutation, a finding that could be exploited to improve therapeutic outcomes in patients harboring CAZ resistant B. pseudomallei. Our study is the first to functionally characterize CAZ resistance in clinical isolates of B. pseudomallei and to provide proven and clinically relevant signatures for monitoring the development of antibiotic resistance in this important pathogen. © 2012 Sarovich et al.

Details

Title: Characterization of ceftazidime resistance mechanisms in clinical isolates of burkholderia pseudomallei from Australia
Authors: Derek S Sarovich (Author) - Northern Arizona University, United States
Erin P Price (Author) - Northern Arizona University, United States
A T von Schulze (Author) - Northern Arizona University, United States
J M Cook (Author) - Northern Arizona University, United States
M Mayo (Author) - Menzies School of Health Research
L M Watson (Author) - Northern Arizona University, United States
L Richardson (Author) - Menzies School of Health Research
M L Seymour (Author) - Northern Arizona University, United States
A Tuanyok (Author) - Northern Arizona University, United States
D M Engelthaler (Author) - Translational Genomics Research Institute, United States
T Pearson (Author) - Northern Arizona University, United States
S J Peacock (Author) - Mahidol University, Thailand
B J Currie (Author) - Menzies School of Health Research
P Keim (Author) - Northern Arizona University, United States
D M Wagner (Author) - Northern Arizona University, United States
Publication details: PLoS One, Vol.7(2), e30789
Publisher: Public Library of Science
Date published: 2012
DOI: 10.1371/journal.pone.0030789
ISSN: 1932-6203; 1932-6203
Copyright note: Copyright © 2012 Sarovich et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Organisation Unit: University of the Sunshine Coast, Queensland; Centre for Bioinnovation
Language: English
Record Identifier: 99450525502621
Output Type: Journal article
Research Statement: false

Metrics

33 File views/ downloads

327 Record Views

71 Times Cited - Web of Science

InCites Highlights

These are selected metrics from InCites Benchmarking & Analytics tool, related to this output

Collaboration types: Domestic collaboration; International collaboration
Web Of Science research areas: Microbiology

UN Sustainable Development Goals (SDGs)

This output has contributed to the advancement of the following goals:

Source: InCites