Sulfhydryl-containing protozoan metabolic enzymes

Sulfhydryl-containing protozoan metabolic enzymes are a diverse group of proteins essential for the survival and pathogenesis of various parasitic protozoa, including Trypanosoma, Leishmania, and Entamoeba species. These enzymes are characterized by the presence of critical sulfhydryl (-SH) groups, typically from cysteine residues, which are essential for their catalytic activity or structural stability. Key members of this group include enzymes involved in glycolysis, such as pyruvate kinase and phosphofructokinase, as well as enzymes central to the parasite's unique redox metabolism, such as trypanothione reductase. Because these enzymes are vital for energy production and protection against oxidative stress, they are primary targets for several classic antiparasitic agents. Drugs like melarsoprol and pentavalent antimonials (e.g., sodium stibogluconate) function by covalently binding to these sulfhydryl groups, thereby inactivating the enzymes and leading to parasite death. However, the lack of absolute specificity for parasite enzymes often results in significant host toxicity, making the management of these infections clinically challenging.

Other names

Thiol-containing protozoan enzymesSulfhydryl-dependent protozoan enzymesProtozoan thiol-containing metabolic enzymes

Covalent inhibition of enzymes through binding to sulfhydryl groups, disrupting glycolysis and redox balance.