Proteases cysteine

In the rosary pea Abrus precatorius L. Trigollenine as well as its gallic acid ester Precatorine (209) is found (71P195) (Scheme 69). 1-Carboxymethyl-nicotinic acid (210) was isolated as a colorless solid from the marine sponge Anthosigmella cf. raromicrosclera as a cysteine protease inhibitor (98JNP671). This compound was first synthesized in 1991. The sodium... 

More recently, miraziridine A (113) was isolated from a marine sponge related to Theonella mirabilis and shown to inhibit the cysteine protease cathepsin B. It has been shown that the aziridine ring plays a key role in this biological activity and gives rise to irreversible inhibition of cathepsins B and L, presumably through... 

In higher organisms, calpain superfamily contains 16 independent genes that modulate cellular function. Out of them, 14 are Ca2+-dependent cysteine proteases. The other two encode smaller regulatory proteins that... 

Modification by SUMO is a reversible and often highly dynamic process. Cleavage of the isopeptide bond between SUMO and its targets is accomplished by SUMO specific cysteine proteases of the Ulp/SENP family (Fig. 2). Six members were identified in humans,... 

Rhinoviruses, which represent the single major cause of common cold, belong to the family of picornavimses that harbors many medically relevant pathogens. Inhibitors of the 3C protease, a cysteine protease, have shown good antiviral potential. Several classes of compounds were designed based on the known substrate specificity of the enzyme. Mechanism-based, irreversible Michael-acceptors were shown to be both potent inhibitors of the purified enzyme and to have antiviral activity in infected cells. 

Structural analysis of the rhinovirus and the hepatitis A virus 3C proteases (Allaire et al. 1994 Matthews et al. 1994) confirmed earlier predictions that the picomavirus 3C proteases are similar to chymotrypsin-Uke serine proteases in their fold. An important difference is that the serine nucleophile of serine proteases is replaced with a cysteine however, the 3C protease is stracturally distinct from the eukaryotic cysteine protease class of enzymes. 

Desai PV, Patny A, Sabnis Y, Tekwani B, Gut J, Rosenthal P, Srivastava A, Avery M. Identification of novel parasitic cysteine protease inhibitors using virtual screening. 1. The ChemBridge database. / Med Chem 2004 47 6609-15. 

Rhinoviri are the causal agents of common colds in humans. Viral replication and maturation is dependent on proteolytic processing of a viral polyprotein by a cysteine protease known as 3C protease. The active-site cysteine in 3C protease... 

Falcone, F., Tetteh, K.K.A., Hunt, P., Blaxter, M.L., Loukas, A.C. and Maizels, R.M. (2000) The new subfamily of cathepsin Z-like protease genes includes Tc-cpz-1, a cysteine protease gene expressed in Toxocara canis adults and infective larvae. Experimental Parasitology 94, 201-203. 

Loukas, A., Selzer, P.M. and Maizels, R.M. (1998) Characterisation of Tc-cpl-1, a cathepsin L-like cysteine protease from Toxocara canis infective larvae. Molecular and Biochemical Parasitology 92, 275—289. 

TSBP 37 to 97 Cysteine proteases Suffolk Cross 77 47 Knox etal., 1999... 

The N-terminal sequence of one peptide from the 35 kDa zone of H-gal-GP showed some homology to cathepsin B-like cysteine proteases. Molecular cloning has also identified a thrombospondin homologue associated with the diffusely staining region between zones A and B, a galectin associated with zone D (Newlands et al., 1999) and a low molecular weight (approximately 13 kDa) cysteine protease inhibitor, cystatin. 

Membrane extracts from adult H. contortus were enriched 24-fold for cysteine protease activity by passage over a Thiol-Sepharose affinity column and the proteins obtained (abbreviated as TSBP) were clearly localized to the microvillar surface of the intestinal cells (Knox et al., 1995,1999). TSBP comprised a prominent 60 kDa protein and several minor bands between 35 and 45 kDa and 97 to 120 kDa (Fig. 13.2). Protease activity at 38, 52 and 70 kDa was attributable to cysteine proteases and at 70 and 88 kDa to serine/metalloproteases, as judged by inhibition analyses. Lectin-binding studies showed that most of the TSBPs were glycosylated. Expression library... 

Fig. 13.4. Comparison of the predicted three-dimensional structure of an H. contortus gut-derived cysteine protease (HMCP1) with that of human cathepsin B.

Cox, G.N., Pratt, D., Hageman, R. and Boisvenue, R.J. (1990) Molecular cloning and sequencing of a cysteine protease expressed by Haemonchus contortus adult worms. Molecular and Biochemical Parasitology 41, 25-34. 

---