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

G Kaslik; A Patthy; M Bálint; L Gráf

doi:10.1016/0014-5793(95)00816-r

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

G Kaslik·A Patthy·M Bálint·L Gráf

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Abstract

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.

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Amino Acid Sequence Animals Asparagine Cattle Chromatography Electrophoresis, Polyacrylamide Gel Humans Molecular Sequence Data Mutation Protein Conformation Rats Serine Trypsin alpha 1-Antitrypsin Comparative Study Journal Article

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G Kaslik, A Patthy, M Bálint, L Gráf. 1995-08-21. Trypsin complexed with alpha 1-proteinase inhibitor has an increased structural flexibility.. https://doi.org/10.1016/0014-5793(95)00816-r

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