China
Africa
Explore chapters and articles related to this topic
Proteases in Leather Processing
Published in Devarajan Thangadurai, Jeyabalan Sangeetha, Industrial Biotechnology, 2017
Vasudeo P. Zambare, Smita S. Nilegaonkar
Cysteine proteases occur in both prokaryotes and eukaryotes. About 20 families of cysteine proteases have been recognized. The activity of all cysteine proteases depends on a catalytic dyad consisting of cysteine and histidine. The order of Cys and His (Cys-His or His-Cys) residues differ among the families (Barett, 1994). Generally, cysteine proteases are active only in the presence of reducing agents such as HCN or cysteine. Based on their side chain specificity, they are broadly divided into four groups, (i) papain-like, (ii) trypsin-like with preference for cleavage at the arginine residue, (iii) specific to glutamic acid, and (iv) others. Papain is the best-known cysteine protease.
Rhenium complexes as antiviral agents for COVID-19
Published in Journal of Coordination Chemistry, 2022
As Mpro is a cysteine protease, the coordination of a metal center to the catalytically active cysteine residue in the active site would present an effective method of inhibiting the activity of this enzyme. To this end, Darensbourg and coworkers investigated the use of Zn(II) thiotropolone complexes. The compounds were found to dissociate in the presence of metal coordinating amino acids such as histidine or cysteine. Computational docking studies suggested that the catalytic cysteine residue could coordinate to the metal center. The Zn(II) thiotropolone complexes gave IC50 values between 79-400 nM, in a similar range as the metal salt Zn(NO3)2, suggesting the metal ion as the determining factor for the inhibitory effect [20]. Despite this promising activity, the rapid speciation of these complexes in a biological milieu limits the application of such compounds, requiring the need for optimization of the ligand scaffold.