Structure-function relationships in human alpha- and gamma-thrombins.

L J Berliner

doi:10.1007/bf00222493

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Structure-function relationships in human alpha- and gamma-thrombins.

L J Berliner

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Abstract

Human pro-coagulant alpha-thrombin may be proteolyzed under controlled conditions to the non-coagulant beta- and gamma-thrombin forms. These derivative forms nonetheless retain esterase and amidase activities with small substrates as well as several other thrombin functions. Structurally, human gamma-thrombin consists of three non-covalently associated fragments which retain structural integrity as measured by several spectroscopic criteria as well as enzymatic function. The protein folding characteristics of three-chain gamma-thrombin indicate that each fragment (domain) contains sufficient information to result in a correct renaturation of protein conformation. Those subtle structural differences which distinguish gamma- from alpha-thrombin are most likely the obstructions to fibrinogen binding which account for the loss of clotting activity.

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Binding Sites Electron Spin Resonance Spectroscopy Hemostasis Humans Models, Molecular Molecular Weight Peptide Fragments Protein Binding Protein Conformation Spectrometry, Fluorescence Structure-Activity Relationship Thrombin Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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L J Berliner. 1984. Structure-function relationships in human alpha- and gamma-thrombins.. https://doi.org/10.1007/bf00222493

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