Targeting the cysteine biosynthesis pathway in microorganisms: Mechanism, structure, and drug discovery.

Owing to the global health crisis of resistant pathogenic infections, researchers are emphasizing the importance of novel prevention and control strategies. Existing antimicrobial drugs predominantly target a few pathways, and their widespread use has pervasively increased drug resistance. Therefore, it is imperative to develop new antimicrobial drugs with novel targets and chemical structures. The de novo cysteine biosynthesis pathway, one of the microbial metabolic pathways, plays a crucial role in pathogenicity and drug resistance. This pathway notably differs from that in humans, thereby representing an unexplored target for developing antimicrobial drugs. Herein, we have presented an overview of cysteine biosynthesis pathways and their roles in the pathogenicity of various microorganisms. Additionally, we have investigated the structure and function of enzymes involved in these pathways as well as have discussed drug design strategies and structure-activity relationships of the enzyme inhibitors. This review provides valuable insights for developing novel antimicrobials and offers new avenues to combat drug resistance.