Plasmepsin

Plasmepsins are a class of at least 10 enzymes produced by the plasmodium parasite. Through their haemoglobin-degrading activity, they are an important cause of symptoms in malaria sufferers. This family of enzymes is a potential target for antimalarial drugs.

Plasmepsins are aspartic acid proteases, which means their active site contains two aspartic acid residues. These two aspartic acid residue act respectively as proton donor and proton acceptor, catalysing the hydrolysis of peptide bond in proteins.

There are four types of plasmepsins, closely related but varying in the specificity of cleavage site. Plasmepsins I and II cleave hemoglobin between residues Phenylalanine 33 and Leucine 34 of &alpha;-globin subunit.

The name plasmepsin may come from plasmodium (the organism) and pepsin (a common aspartic acid protease with similar molecular structure).