Investigation of WQ-3810, a Fluoroquinolone with a High Potential Against Fluoroquinolone-Resistant .

, a member of complex (MAC), is an emerging opportunistic pathogen causing MAC-pulmonary disease (PD). Fluoroquinolones (FQs), along with ethambutol (EMB) and rifampicin, are recommended for macrolide-resistant MAC-PD; however, FQ-resistant have been reported worldwide. WQ-3810 is an FQ with high potency against FQ-resistant pathogens; however, its activity against has not yet been studied.

Interplay between Amino Acid Substitution in GyrA and QnrB19: Elevating Fluoroquinolone Resistance in Typhimurium.

Globally, there have been increasing reports of antimicrobial resistance in nontyphoidal (NTS), which can develop into severe and potentially life-threatening diarrhea. This study focuses on the synergistic effects of DNA gyrase mutations and plasmid-mediated quinolone resistance (PMQR) genes, specifically , on fluoroquinolone (FQ) resistance in Typhimurium. By utilizing recombinant mutants, GyrA and GyrA, and QnrB19's, we discovered a significant increase in fluoroquinolones resistance when QnrB19 is present.

Effect of WQ-3334 on Campylobacter jejuni carrying a DNA gyrase with dominant amino acid substitutions conferring quinolone resistance.

Introduction: Campylobacteriosis stands as one of the most frequent bacterial gastroenteritis worldwide necessitating antibiotic treatment in severe cases and the rise of quinolones-resistant Campylobacter jejuni poses a significant challenge. The predominant mechanism of quinolones-resistance in this bacterium involves point mutations in the gyrA, resulting in amino acid substitution from threonine to isoleucine at 86th position, representing more than 90% of mutant DNA gyrase, and aspartic acid to asparagine at 90th position. WQ-3334, a novel quinolone, has demonstrated strong inhibitory activity against various bacteria.

Exploration of the novel fluoroquinolones with high inhibitory effect against quinolone-resistant DNA gyrase of Typhimurium.

Quinolone-resistant nontyphoidal is a pressing public health concern, demanding the exploration of novel treatments. In this study, we focused on two innovative synthetic fluoroquinolones, WQ-3034 and WQ-3154. Our findings revealed that these new compounds demonstrate potent inhibitory effects, even against mutant strains that cause resistance to existing quinolones.

Characterization of DNA Gyrase Activity and Elucidation of the Impact of Amino Acid Substitution in GyrA on Fluoroquinolone Resistance in Mycobacterium avium.

Mycobacterium avium, a member of the M. avium complex (MAC), is the major pathogen contributing to nontuberculous mycobacteria (NTM) infections worldwide. Fluoroquinolones (FQs) are recommended for the treatment of macrolide-resistant MACs.