Serine endopeptidase

Cysteine endopeptidases, like serine endopeptidases, can also catalyze peptide synthesis under preparative conditions [66-68]. Thus, papain has been used to synthesize enkephalins and angiotensin. 

The /3-lactam structure can also react with active-serine hydrolases other than PBPs and /3-lactamases. It has been shown that appropriately substituted cephalosporins (e.g., 5.18) are potent mechanism-based inactivators of human leukocyte elastase (HLE, EC 3.4.21.37), a serine endopeptidase involved in the pathogenesis of pulmonary emphysema and other connective tissue diseases [57-60]. Subsequent work has demonstrated that substituted /3-lactams such as 5.19 or 5.20 are more stable HLE inhibitors and have improved potencies [61-63]. 

Serine-endopeptidase Cholecystokinin-C-terminal octapeptide Met3-Gly4... 

This enzyme [EC 3.4.21.62], a serine endopeptidase that evolved independently of chymotrypsin, contains no cys-teinyl residues. This enzyme catalyzes the hydrolysis of peptide bonds in proteins and has a broad specificity, with a preference for a large uncharged aminoacyl residue in the PI subsite. 

Chymotrypsin, a serine endopeptidase, most readily reacts at the carboxyl group of the aromatic amino acid residue of proteins and polypeptides (or N-acyl aromatic amino acid esters) to form first a tetrahedral intermediate which then collapses into an acyl-enzyme (7+ 8- I>). The acyl-enzyme is then hydrolyzed by water to furnish the M-acylated aromatic amino acid again through the formation of a tetrahedral intermediate (JO Jl -> J2) (1-4). 

Du/tripeptidyl-peptidases Peptidyl-dipeptidases Serine carboxypeptidases MetaUocarboxypeptidases Cysteine carboxypeptidases Omega peptidases Serine endopeptidases Cysteine endopeptidases Aspartic endopeptidases MetaUoendopeptidases Threonine endopeptidases Other endopeptidases... 

Bode, W., and Huber, R., 1986. Crystal structure of pancreatic serine endopeptidases. InMolecular and Cellular Basis of Digestion (pp. 213 - 234), edited by P. Desnuelle, H. Sjostrom, and O. Noren. Elsevier. 

Alcalase, a serine endopeptidase from Bacillus licheniformis and whose major component is subtUisin A (subtihsin Carlsberg)[ l has been employed to selectively saponify peptide methyl and benzyl esters (Scheme 16) in a solvent system consisting of 90% tert-butyl alcohol and 10% buffer (pH 8.2) leaving the N-terminal Fmoc group intact. A selective classical alkaline saponification of methyl esters would have been impossible due to the base sensitivity of the Fmoc group. 

Chymotrypsin [ban, inn] (EC 3.4.21.1 Catarase Zonulysin ) is an enzyme (MW c. 25,0(X) a-form). It is a (serine) endopeptidase stored as zymogen in granules of pancreatic P-cells of mammals. It catalyses the hydrolysis of amide and ester bonds of peptides and proteins, particularly those adjacent to the carbonyl group of hydrophobic L-amino acids. Therapeutically, it is used in ocular surgery, especially for removal of cataracts. It was used formerly as a... 

Another beneficial property of the commonly used Bacillus subtilisins is their broad substrate specificity. In contrast to other serine endopeptidases like trypsin and chymotrypsin, the subtilisins have elongated substrate binding sites that allow them to accommodate a wide variety of different peptide sequences. 

Relevant enzymes among the serine hydrolases include car-boxylesterases, arylesterases, cholinesterase and a number of serine endopeptidases [EC 3.4.21], The role of arylsulfa-tases, phosphatases, 3-glucuronidases, epoxide hydrolases and some endopeptidases is also significant. 

Acting on peptide bonds (peptide hydrolases). Serine endopeptidases. 

Krystek S, Stouch T, Novotny J. Affinity and specificity of serine endopeptidase-protein inhibitor interactions. Empirical free energy calculations based on X-ray crystallographic structures. J Mol Biol 1993 234 661-679. 

Serine endopeptidase DORIS Film 68.17 - 108.26 P432i2 1.5 - 16.7 Betzel, Pal and Saenger... 

Trypsin, EC 3.4.21.4, a prototype of the serine endopeptidases family S 1. It was described and named as the proteolytic activity in pancreatic secretions as early as 1876, and purified by crystallization in 1931. Trypsin strongly prefers to cleave peptide substrates following PI Arg or Lys residues peptidases). All naturally occurring trypsins are synthesized as proenzymes. The mammalian propeptide (trypsinogen) contains the consensus sequence for cleavage by enteropeptidase [V. Schellenberger etal., Biochemistry 1994, 33, 4251 J. J. Perona, C. S. Craick, Protein Sci. 1995, 4, 337 L. Hedstrom, Biol. Chem. 1996, 377, 465]. 

Serine endopeptidase Serine in the active site Chymotrypsins A, B and C, peptidase B alkaline, pro-teinases a-and P-trypsin,... 

The serine endopeptidase plasmin is of special interest in milk technology. 

S. Krystek, T. Stouch, and J. Novotny, ]. Mol. Biol., 234,661 0 993). Affinity and Specificity of Serine Endopeptidase-Protein Inhibitor Interactions Empirical Free Energy Calculations Based on X-Ray Crystallographic Structures. 

The serine endopeptidases include the chymotrypsin family (EC 3.4.21.1), trypsin (EC 3.4.21.4), elastase (EC 3.4.21.37), thrombin (EC 3.4.21.5), subtilisin (EC 3.4.21.62) and a-lytic proteases (EC 3.4.21.12). The enzymes are all endopeptidases. The substrate specificities of the individual members of this group are often quite different, which is attributed to different structures of the binding pockets. 

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