Phospholipid-specific conformational changes in human prothrombin upon binding to procoagulant acidic lipid membranes.

J R Wu; B R Lentz

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PubMed · 8091387

Phospholipid-specific conformational changes in human prothrombin upon binding to procoagulant acidic lipid membranes.

J R Wu·B R Lentz

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Abstract

This paper provides evidence to demonstrate that human prothrombin undergoes conformational changes upon binding to procoagulant membranes specifically containing phosphatidylserine (PS). Fourier transform infrared spectroscopy was used to show a slight increase in ordered (alpha-helix, beta-sheet, beta-turns) secondary structure upon binding to PS-containing membranes. Thermograms representing prothrombin and prothrombin fragment 1 denaturation were obtained using differential scanning calorimetry. These were analyzed and interpreted in terms of changes in prothrombin domain organization associated with binding to PS-containing membranes. Changes in either secondary structure or domain organization upon binding to negatively-charged phosphatidylglycerol-containing membranes were, if they occurred at all, much less dramatic. The results paralleled results obtained previously with bovine prothrombin (1, 2). The implications of these results in terms of a possible molecular mechanism for the cofactor-like role of platelet membrane vesicles in prothrombin activation are discussed.

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Acids Amides Animals Cattle Humans Membranes, Artificial Peptide Fragments Phosphatidylserines Protein Binding Protein Denaturation Protein Precursors Protein Structure, Secondary Protein Structure, Tertiary Prothrombin Species Specificity Spectroscopy, Fourier Transform Infrared Journal Article Research Support, U.S. Gov't, P.H.S.

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J R Wu, B R Lentz. 1994. Phospholipid-specific conformational changes in human prothrombin upon binding to procoagulant acidic lipid membranes.. https://pubmed.ncbi.nlm.nih.gov/8091387/

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