The Gal6 protease is in a class of cysteine peptidases identified by their ability to inactivate the anti-cancer drug bleomycin. The protein forms a barrel structure with the active sites embedded in a channel as in the proteasome. In Gal6 the C termini lie in the active site clefts. We show that Gal6 acts as a carboxypeptidase on its C terminus to convert itself to an aminopeptidase and peptid...

The cysteine-type peptidase cathepsin X is highly upregulated in several cancers and presumably promotes tumor invasion through bypassing cellular senescence. Here, we present first evidence that the underlying mechanism may involve the regulation of the insulin-like growth factor (IGF) system, a well-known activator of proliferating tumor cells. Cathepsin X deficiency leads to a reduced phosph...

Signal peptidase, which removes signal peptides from preproteins, has a substrate specificity for small uncharged residues at -1 (P1) and small or larger aliphatic residues at the -3 (P3) position. Structures of the catalytic domain with a 5S-penem inhibitor and a lipopeptide inhibitor reveal candidate residues that make up the S1 and S3 pockets that bind the P1 and P3 specificity residues of t...

Abstract The pandemic of Coronavirus Disease 2019 (COVID-19) is caused by Severe Acute Respiratory Syndrome 2 (SARS-CoV-2). viral fusion protein, spike binds to its receptor Angiotensin-Converting Enzyme (ACE2) enter host cells. Further, the S1 subunit protein may be cleaved off virus and affect various organs. In addition tightly binding ACE2, also enhances peptidase activity ACE2 activate cel...

Background: Regulatory T cells (Tregs) play an essential role in maintaining self-tolerance and immune homeostasis. Abnormalities the quantity or function of Treg are believed RA patients, contributing to inability suppress autoimmunity proinflammatory cytokines. Forkhead box P3 (Foxp3) is a crucial transcription factor for development differentiation Tregs. How Tregs lose Foxp3 expression unde...

There are evidences indicating that cysteine proteases play an essential role in malaria parasites; therefore, an obvious area of investigation is the inhibition of these enzymes to treat malaria. Small cysteine protease inhibitors of malaria are well studied, but macromolecular nature of inhibitor is a new field to explore. In malarial cysteine proteases, there are macromolecular endogenous in...