Molecular characterisation of resistance to fluoroquinolones in Haemophilus parasuis isolated from China
Abstract
There are many studies on fluoroquinolone (FQ) resistance in the literature, but little is known regarding the molecular characterisation of FQ-resistant Haemophilus parasuis. In this study, a total of 138 H. parasuis isolates were examined, among which 83 (60.1%) were resistant to enrofloxacin (EFX) and 8 (5.8%) were resistant to levofloxacin (LFX) as determined by Etest. Ten point mutations in the quinolone resistance-determining regions of gyrA, gyrB, parC and parE were detected by PCR and DNA sequencing. Interestingly, 100% of the resistant isolates contained mutations at 87D of gyrA, but other mutations occurred less frequently. Furthermore, it was found that there was synergy between 73S→R/I in parC and other point mutations with respect to FQ resistance. To examine the effect of different point mutations on FQ resistance, the minimum inhibitory concentrations of EFX and LFX were determined for strains generated by site-directed mutagenesis, and three point mutations (gyrA 87D→N, parC 73S→R and parE 551T→A) were shown to be involved in FQ resistance.
Read the paper
Related studies
- Ferulic acid regulates the AKT/GSK-3β/CRMP-2 signaling pathway in a middle cerebral artery occlusion animal model
- Novel Pharmacokinetic/Pharmacodynamic Parameters Quantify the Exposure–Effect Relationship of Levofloxacin against Fluoroquinolone-Resistant Escherichia coli
- Photochemical behavior of levofloxacin
- Correlation Between Dissolution Profiles of Salt-Form Drugs in Biorelevant Bicarbonate Buffer and Oral Drug Absorption: Importance of Dose/ Fluid Volume Ratio
- Evaluation of the synergistic potential and mechanisms of action for de novo designed cationic antimicrobial peptides
- Synthesis of [11C]levofloxacin
Go deeper in Evidence Hub
Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.