Porcine pancreatic trypsin

Song, H.K. S.W. Suh. Complex porcine pancreatic trypsin/soybean trypsin inhibitor, tetragonal crystal form. Deposited 1997. http //pdbbeta.rcsb.org/pdb/explore.do structureId=lAVX. 

An enzyme-catalyzed Biginelli reaction has been reported by Zhang et al. [84]. Porcine pancreatic trypsin showed to be the most effective enzyme among 13 enzymes tested. The reactions were conducted in anhydrous ethanol at 37 °C for 72 h and the desired products could be isolated in good to excellent yields. 

Because of its role in the digestive system, animal pancreas is rich source of secreted proteases and lipases. Pancreatin from porcine pancreas is a mixture of different enzymes capable of hydrolyzing carbohydrates, lipids, esters, amides and proteins. It can be used directly when the presence of competing catalysts are not a problem. Several individual pancreatic enzymes are also readily available. Porcine pancreatic lipase has been widely used in synthesis. Several proteases from this source are sold commercially and used extensively. Porcine pancreatic trypsin is an inexpensive serine protease that hydrolyzes peptide bonds predominantly on the carboxyl side of lysines or arginines in proteins and peptides. Chymotrypsin is another serine protease from the same source that cleaves amide bonds on the carboxyl side of large hydrophobic amino adds such as tyrosine tryptophan, phenylalanine, and, to a lesser extent, leudne. Several different subtypes of chymotrypsin are known, for example, a-, 3-, y-, with... 

Human aranti-trypsin (AAT) 22 mgh1 Inhibition of porcine pancreatic elastase Heterogeneous [17]... 

Chymo trypsin protease bovine or porcine pancreatic extract none 3.4.21.1... 

Our knowledge of porcine pancreatic phospholipase comes from the laboratory of G. H. de Haas and his co-workers. The enzyme is quite different from pancreatic lipase (Table VIII). Its molecular weight is quite small, it is a metalloenzyme that requires Ca ion as a cofactor, and it is excreted from the pancreas as a proenzyme which is then activated by trypsin with removal of a heptapeptide. The molecule has six... 

Phe(J)B ]insulm Porcine proinsulin Acetamidino-insulin Bic(Boc) insulin Des-Al-amino-insulin Destripeptide B - bovine insulin 58-Unit Peptides Bovine basic pancreatic trypsin inhibitor... 

In the field of organic synthesis, it was reported that the catalytic hydrolysis of umbelliferone esters (7-acetoxycoumarin) to 7-hydroxycoumarinby porcine pancreatic lipase covalently immobilized on microchannel reactors almost completed within 1 min, to be compared with 4 min in a normal batch reaction [86]. The same group demonstrated an improvement in the yield of trypsinmicrochannel reactor with a lower enzyme concentration but a 20-fold higher reaction rate than in a batch reactor [87]. 

The action of trypsin on porcine pancreatic a-amylase has been studied. Characterization of the released fragments showed that trypsinolysis of this a-amylase is incomplete. Chemical studies e.g. 2,4-dinitrophenylation and dansylation, etc.) have indicated that porcine pancreatic a-amylase contains an N-acetylated amino-acid at the NHj-terminus and leucine at the COjH-terminus. These findings support the view that the enzyme consists of a single chain, rather than of a subunit or a multi-chain structure. 

Inhibitors of proteolytic enzymes. Acc. Chem. Res. 7, 315-320. Melville, J. C., and Ryan, C. A. (1972). Chymotrypsin InTiibltor I from potatoes. Large scale preparation and characterization of Its subunit components. J. Biol. Chem. 247, 3445-3453. Menegatti, E., Tomatls, R., Guarner, M., and Scatturin, A. (1981). Conformational stability of porcine-pancreatic secretory trypsin Inhibitors (Kazal Inhibitors). Int. J. Pept. Protein Res. 17, 454-459. 

Siehczyk and co-workers have presented the synthesis and the measurement of the inhibitory activity of novel peptidyl derivatives of a-aminoalkylphosphonate diaryl esters (449) as human neutrophil elastase (HNE) inhibitors. Their selectivity against other serine proteases, including porcine pancreatic elastase, chymotrypsin, and trypsin, has also been demonstrated. The compound (450) displayed the best balance of high inhibitory activity against HNE and selectivity for HNE over porcine... 

Figure 2. SDS gel electrophoresis of the products of partial cystine cleavage for several test proteins. A. molecular weight standards, B. yeast alcohol dehydrogenase. C. P-lactoglobulin, D. hen egg lysozyme, E. ovalbumin, F. calf fetal serum fetuin. Molecular weight standards are indicated by arrows on the left side of the gel and are bovine serum albumin (66,300), bovine liver glutamate dehydrogenase (55,400), porcine muscle lactate ddiydiogenase (36,500), bovine erythrocyte carbonic anhydrase (31,000), soybean trypsin inhibitor (21,500), hen egg lysozyme (14,400), bovine lung aprotinin (6,000), unresolved bovine pancreatic insulin A and B chains.

Although pancreatic secretory trypsin inhibitor (Kazal inhibitor) has not been studied by DSC to our knowledge, it is included because it is homologous to the domains of ovomucoids and ovoinhibi-tors (Laskowski and Kato, 1980). Both the porcine and bovine Kazal inhibitors are relatively stable (Menegatti et al., 1981 De Marco et al., 1982), but less so than the Kunitz inhibitor (BPTI). 

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