Rapid bacteriolysis of by lysin exebacase.

Lysins (peptidoglycan hydrolases) are promising new protein-based antimicrobial candidates under development to address rising antibiotic resistance encountered among pathogenic bacteria. Exebacase is an antistaphylococcal lysin and the first member of the lysin class to have entered clinical trials in the United States. In this study, the bacteriolytic activity of exebacase was characterized with time-kill assays, turbidity reduction assays, and microscopy.

Discovery of Novel UDP--Acetylglucosamine Acyltransferase (LpxA) Inhibitors with Activity against .

This study describes a novel series of UDP--acetylglucosamine acyltransferase (LpxA) inhibitors that was identified through affinity-mediated selection from a DNA-encoded compound library. The original hit was a selective inhibitor of LpxA with no activity against LpxA. The biochemical potency of the series was optimized through an X-ray crystallography-supported medicinal chemistry program, resulting in compounds with nanomolar activity against LpxA (best half-maximal inhibitory concentration (IC) <5 nM) and cellular activity against (best minimal inhibitory concentration (MIC) of 4 μg/mL).

Effect of Susceptibility Testing Conditions on the In Vitro Antibacterial Activity of ETX0914.

The effect of various conditions including pH, inoculum, temperature, atmosphere, divalent cations, and several body fluids on the in vitro activity of the novel antibacterial spiropyrimidinetrione ETX0914 in standard susceptibility tests was investigated against several species. None of the parameters investigated affected the activity of ETX0914, with the exception of pH. Whereas the MIC values for ETX0914 with S.

Molecular mechanisms of sulbactam antibacterial activity and resistance determinants in Acinetobacter baumannii.

Sulbactam is a class A β-lactamase inhibitor with intrinsic whole-cell activity against certain bacterial species, including Acinetobacter baumannii. The clinical use of sulbactam for A. baumannii infections is of interest due to increasing multidrug resistance in this pathogen.

Novel N-linked aminopiperidine inhibitors of bacterial topoisomerase type II: broad-spectrum antibacterial agents with reduced hERG activity.

Novel non-fluoroquinolone inhibitors of bacterial type II topoisomerases (DNA gyrase and topoisomerase IV) are of interest for the development of new antibacterial agents that are not impacted by target-mediated cross-resistance with fluoroquinolones. Aminopiperidines that have a bicyclic aromatic moiety linked through a carbon to an ethyl bridge, such as 1, generally show potent broad-spectrum antibacterial activity, including quinolone-resistant isolates, but suffer from potent hERG inhibition (IC(50)= 3 μM for 1). We now disclose the finding that new analogues of 1 with an N-linked cyclic amide moiety attached to the ethyl bridge, such as 24m, retain the broad-spectrum antibacterial activity of 1 but show significantly less hERG inhibition (IC(50)= 31 μM for 24m) and higher free fraction than 1.