[Proteolytic activity of the enzyme complex of the mammalian pancreas in comparison with pancreatin].

The proteolytic activity and thermal stability of the enzyme complex of cell suspension from pig and bovine pancreas glands was compared with those of pancreatin. The enzyme complex displayed the highest thermal stability and activity at 50 degrees C. The kinetic constants, energies of activation and inactivation of the enzyme complex, and pH optimum (7.

[Production of human insulin from proinsulin by a biological catalysis].

The conversion of porcine and human proinsulins to insulin by enzymatic hydrolysis induced by trypsin and carboxypeptidase B was studied. The conditions of reactions in the presence of trypsin (pure or immobilized in PAAG) and carboxypeptidase B were determined. The possibility of insulin production by the use of immobilized trypsin and carboxypeptidase B for practical purposes was shown.

[Biosynthesis and isolation of a recombinant protein for producing genetically-engineered human proinsulin].

Isolation of the recombinant protein from a genetically engineered Escherichia coli 1854 producer for further chemical enzymatic transformation into human insulin through proinsulin was studied. Under optimal conditions, the recombinant protein formation was more than 35% of the total cell proteins. Structures of the polypeptides obtained and purified chromatographically were confirmed by amino acid analysis.