Role of tcaA, a potential target as a ceftobiprole resistance breaker in MRSA β-lactam resistance.

Objectives: Using a random forest algorithm, we previously found that teicoplanin-associated gene A (tcaA) might play a role in resistance of methicillin-resistant Staphylococcus aureus (MRSA) to β-lactams, which we have investigated further here.

Methods: Representative MRSA strains of prevalent clones were selected to identify the role of tcaA in the MRSA response to β-lactams. tcaA genes were deleted by homologous recombination in the selected MRSA strains, and antibiotic susceptibility tests were applied to evaluate the effect of tcaA on the minimum inhibitory concentrations (MICs) of glycopeptides and β-lactams.

Identification of the novel fosfomycin resistance gene fosSC in Staphylococcus capitis.

Objectives: Fosfomycin has regained attention for treating infections caused by methicillin-resistant Staphylococcus aureus and multidrug-resistant coagulase-negative staphylococci. In this research, our objective was to investigate the mechanisms underlying fosfomycin resistance in Staphylococcus capitis.

Methods: The minimum inhibitory concentrations (MICs) of fosfomycin were assessed in 109 clinical S.

Profiling daptomycin resistance among diverse methicillin-resistant lineages in China.

Daptomycin (DAP) is effective against methicillin-resistant (MRSA). However, reduced susceptibility to DAP in MRSA may lead to treatment failures. We aim to determine the distribution of DAP minimum inhibitory concentrations (MICs) and DAP heteroresistance (hDAP) among MRSA lineages in China.

Exploring the third-generation tetracycline resistance of multidrug-resistant livestock-associated methicillin-resistant Staphylococcus aureus ST9 across healthcare settings in China.

Background: The overuse of antibiotics in livestock is contributing to the burden of antimicrobial resistance in humans, representing a One Health challenge. Livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) has recently become a growing concern, and ST9 is the major LA-MRSA lineage in China and has emerged in clinical settings.

Methods: Antimicrobial susceptibility testing was used to evaluate the tetracycline resistance of ST9 MRSA collections, and gene cloning experiments were performed to explore the resistance mechanisms.