Comparative in vitro activities of GSK2251052, a novel boron-containing leucyl-tRNA synthetase inhibitor, against 916 anaerobic organisms.

We studied the comparative in vitro activity of GSK2251052, a novel boron leucyl-tRNA synthetase inhibitor, against 916 clinical anaerobic isolates using CLSI methods. The GSK MIC50/MIC90 for all isolates tested were 2 and 4 μg/ml, and the MIC90s against 302 Bacteroides fragilis and Bacteroides thetaiotaomicron strains were 4 and 8 μg/ml, respectively. All Clostridium perfringens strains had GSK2251052 MICs of >32 μg/ml. There was no relationship between increased MICs for any other antibiotics and that of GSK2251052.