Can Inhibitor-Resistant Substitutions in the Mycobacterium tuberculosis β-Lactamase BlaC Lead to Clavulanate Resistance?: a Biochemical Rationale for the Use of β-Lactam–β-Lactamase Inhibitor Combinations

Can Inhibitor-Resistant Substitutions in The Mycobacterium Tuberculosis Î2-Lactamase BlaC Lead to Clavulanate Resistance?: A Biochemical Rationale for The Use of Î2-Lactamâ•fiÎ2-Lactamase Inhibitor Combinations

Hydrolysis of clavulanate by Mycobacterium tuberculosis β-lactamase BlaC harboring a canonical SDN motif.

Combinations of β-lactams with clavulanate are currently being investigated for tuberculosis treatment. Since Mycobacterium tuberculosis produces a broad spectrum β-lactamase, BlaC, the success of this approach could be compromised by the emergence of clavulanate-resistant variants, as observed for inhibitor-resistant TEM variants in enterobacteria. Previous analyses based on site-directed muta...

The β-lactamase inhibitor avibactam (NXL104) does not induce ampC β-lactamase in Enterobacter cloacae

Induction of ampC β-lactamase expression can often compromise antibiotic treatment and is triggered by several β-lactams (such as cefoxitin and imipenem) and by the β-lactamase inhibitor clavulanic acid. The novel β-lactamase inhibitor avibactam (NXL104) is a potent inhibitor of both class A and class C enzymes. The potential of avibactam for induction of ampC expression in Enterobacter cloacae...

Efficacy of β-lactam/β-lactamase inhibitor combination is linked to WhiB4-mediated changes in redox physiology of Mycobacterium tuberculosis

Mycobacterium tuberculosis (Mtb) expresses a broad-spectrum β-lactamase (BlaC) that mediates resistance to one of the highly effective antibacterials, β-lactams. Nonetheless, β-lactams showed mycobactericidal activity in combination with β-lactamase inhibitor, clavulanate (Clav). However, the mechanistic aspects of how Mtb responds to β-lactams such as Amoxicillin in combination with Clav (refe...

The effect of silver nanoparticles on Gram-negative bacilli Resistant to Extended-Spectrum Β-Lactamase Enzymes

Abstract: Background and objectives: Antibiotic resistant to Antimicrobial agents is one of the most important concern in hospitals, which can lead to increased costs, treatment fails and mortality rates. The aim of this study was identification of Gram-negative bacilli resistant to extended-spectrum β-lactamase Enzymes (ESBLs) and determination of the effect of silver nanoparticles on the...