Kaslik, G., Patthy, A., Bálint, M. & Gráf, L.

Trypsin complexed with alpha 1-proteinase inhibitor has an increased structural flexibility.

FEBS Lett 370, 179-83.

Mutant rat trypsin Asp189Ser was prepared and complexed with highly purified human alpha 1-proteinase inhibitor. The complex formed was purified to homogeneity and studied by N-terminal amino acid sequence analysis and limited proteolysis with bovine trypsin. As compared to uncomplexed mutant trypsin, the mutant enzyme complexed with alpha 1-proteinase inhibitor showed a highly increased susceptibility to enzymatic digestion. The peptide bond selectively attacked by bovine trypsin was identified as the Arg117-Val118 one of trypsin. The structural and mechanistic relevance of this observation to serine proteinase-substrate and serine proteinase-serpin reactions are discussed.

Gráf, L.

The structural basis of serine protease action: the fourth dimension.

In Natural Sciences and Human Thought (Zwilling, R., ed.), pp. 139-148. Springer-Verlag, Heidelberg.