Hydrogen sulphide (H₂S), the third endogenous gaseous signalling molecule, has attracted attention in biochemical research. The selective detection of H₂S in living systems is essential for studying its functions. Fluorescence detection methods have become useful tools to explore the physiological roles of H₂S because of their real-time and non-destructive characteristics. Herein we report a near-infrared fluorescent probe, NIR-HS, capable of tracking H₂S in living organisms. With high sensitivity, good selectivity and low cytotoxicity, NIR-HS was able to recognize both the exogenous and endogenous H₂S in living cells. More importantly, it realized the visualization of endogenous H₂S generated in cells overexpressing cystathionine β-synthase (CBS), one of the enzymes responsible for producing endogenous H₂S. The probe was also successfully applied to detect both the exogenous and endogenous H₂S in living mice. The superior sensing properties of the probe render it a valuable research tool in the H₂S-related medical research.

Peptide deformylase (PDF) is a metalloprotease catalyzing the removal of a formyl group from newly synthesized proteins, which makes it an important antibacterial drug target. Given the importance of PDF inhibitors like actinonin in antibacterial drug discovery, several reported potent PDF inhibitors were used to develop pharmacophore models using the Galahad module of Sybyl 7.1 software. Generated pharmacophore models were composed of two donor atom centers, four acceptor atom centers and two hydrophobic groups. Model-1 was screened against the Zinc database and several compounds were retrieved as hits. Compounds with Qfit values of more than 60 were employed to perform a molecular docking study with the receptor Escherichia coli PDF, then compounds with docking score values of more than 6 were used to predict the in silico pharmacokinetic and toxicity risk via OSIRIS property explorer. Two known PDF inhibitors were also used to perform a molecular docking study with E. coli PDF as reference molecules. The results of the molecular docking study were validated by reproducing the crystal structure of actinonin. Molecular docking and in silico pharmacokinetic and toxicity prediction studies suggested that ZINC08740166 has a relatively high docking score of 7.44 and a drug score of 0.78.