Metallo-b-lactamases (MBLs), produced by an increasing number of bacterial pathogens, facilitate the hydrolysis of many commonly used b-lactam antibiotics. There are no clinically useful antagonists against MBLs. Two sets of tetrahydropyrimidine-2-thione and pyrrole derivatives were synthesized and assayed for their inhibitory effects on the catalytic activity of the IMP-1 MBL from Pseudomonas aeruginosa and Klebsiella pneumoniae. Nine compounds tested (1a, 3b, 5c, 6b, 7a, 8a, 11c, 13a, and 16a) showed micromolar inhibition constants (K i values range from 20-80 lM). Compounds 1c, 2b, and 15a showed only weak inhibition. In silico docking was employed to investigate the binding mode of each enantiomer of the strongest inhibitor, 5c (K i = 19 ± 9 lM), as well as 7a (K i = 21 ± 10 lM), the strongest inhibitor of the pyrrole series, in the active site of IMP-1.

This study aimed at clarifying the relationship of Haemophilus aegyptius and Haemophilus influenzae isolated from acute conjunctivitis in Egypt. Twenty‐nine freshly isolated strains selected from a large clinical material were examined for morphological and growth characteristics, biochemical properties and susceptibility to selected antibiotics. H. aegyptius strains were clearly differentiated from strains of H. influenzae by their inability to grow on tryptic soy agar containing X + V factors, by their susceptibility to trooleandomycin, by a distinct bacillary morphology, and, in part, by not fermenting xylose. The results confirm that H. aegyptius is distinct from H. influenzae and provides reproducible means of differentiating the two species.