Antibiotic resistance is one of the most serious global
health
threats. Therefore, there is a need to develop antimicrobial agents
with new mechanisms of action. Targeting of bacterial cystathionine
γ-lyase (bCSE), an enzyme essential for bacterial survival,
is a promising approach to overcome antibiotic resistance. Here, we
described a series of (heteroarylmethyl)benzoic acid derivatives and
evaluated their ability to inhibit bCSE or its human ortholog hCSE
using known bCSE inhibitor NL2 as a lead compound. Derivatives bearing
the 6-bromoindole group proved to be the most active, with IC50 values in the midmicromolar range, and highly selective
for bCSE over hCSE. Furthermore, none of these compounds showed significant
toxicity to HEK293T cells. The obtained data were rationalized by
ligand-based and structure-based molecular modeling analyses. The
most active compounds were also found to be an effective adjunct to
several widely used antibacterial agents against clinically relevant
antibiotic-resistant strains of such bacteria as Staphylococcus
aureus, Klebsiella pneumoniae, and Pseudomonas aeruginosa. The
most potent compounds, 3h and 3i, also showed
a promising in vitro absorption, distribution, metabolism,
and excretion (ADME) profile. Finally, compound 3i manifested
potentiating activity in pneumonia, sepsis, and infected-wound in vivo models.