A novel parC mutation potentiating fluoroquinolone resistance in Klebsiella pneumoniae and Escherichia coli clinical isolates
DOI:
https://doi.org/10.3855/jidc.15142Keywords:
Klebsiella pneumonia, Escherichia coli, gyrA, parC, Fluoroquinolones, MutationsAbstract
Introduction: Resistance to fluoroquinolones is mainly due to point mutations that gave rise to amino acid substitutions in the quinolone resistance-determining regions of either gyrA or parC genes, which may be augmented by plasmid mediated resistance. Accordingly, the main aim of the study was to investigate the mutations in gyrA and parC genes as well as the qnrA and qnrB genes acquisition.
Methodology: 193 Klebsiella pneumoniae and Escherichia coli isolates were collected, identified and MICs for ciprofloxacin, levofloxacin and moxifloxacin were determined. Polymerase Chain Reaction to investigate qnrA, qnrB, gyrA and parC genes followed by DNA sequencing analysis to identify mutations in gyrA and parC genes.
Results: The most prominent mutation in gyrA gene was ser83leu, followed by asp87asn, and lys154arg. Regarding parC mutations, ser80ile was the most detected. Other mutations val141ala and glu84ala were also noted. In addition to a substitution mutation at codon 157 of leucine to tyrosin. To the best of our knowledge this mutation was not previously reported. qnrB was the most detected gene, as 64.7% Klebsiella pneumoniae and 57.1% Escherichia coli were positive. qnrA gene was detected in 11% Klebsiella pneumoniae and 4% of Escherichia coli isolates tested.
Conclusions: This study suggests that the indiscriminate use of fluoroquinolones resulted in the increase of development of resistance either through mutations in the quinolone resistance-determining regions of either gyrA or parC genes augmented by plasmid mediated resistance. The irrational use of new fluoroquinolones such as moxifloxacin has created selective pressure for the appearance of new mutation.
Downloads
Published
How to Cite
Issue
Section
License
Authors who publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).