Cathepsin A

The lysosomal protective protein ( PPCA ) (also: cathepsin A or serine carboxypeptidase A) is a protein that binds as a dimer to lysosomal enzymes ( β -galactosidases and neuraminidase ) and stabilizes them. It is therefore essential in the breakdown of glycosphingolipids. PPCA additionally acts as a peptidase, which is able to separate a wide range of terminal amino acids from proteins. This exopeptidase activity is found in all animals and may be part of antigen presentation in B cells. In humans, mutations in the CTSA gene for rare inherited galactosialidosis.

Inhibitors of protease activity are antipain, ebelactone A, Piperastatin A.

Human Genome Organisation MEROPS Lysosome Digital Object Identifier
169589
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