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Updated: Feb 8, 2026

Analysis of β-Amyloid-induced Abnormalities on Fibrin Clot Structure by Spectroscopy and Scanning Electron Microscopy
Published on: November 30, 2018
Structure of the lysine-fibrin binding subsite of human plasminogen kringle 4
1Department of Chemistry, Michigan State University, East Lansing 48824.
Abstract:
Human plasminogen kringle 4, which crystallizes in the orthorhombic system a = 32.15(2), b = 49.01(2), c = 49.04(3) A, space group P2(1)2(1)2(1), four molecules per unit cell, protein volume fraction 0.62, has been determined at 1.9 A resolution. The structure was solved by rotation-translation methods using the structure of bovine prothrombin kringle 1 as a model and it has been refined at 1.9 A resolution to an R-value of 0.142. The root mean square (rms) deviation between the main-chain atoms of the two kringles is about 0.5 A while that between 31 conserved side chains is a surprisingly large 1.2 A. The structure of the lysine binding subsite of fibrin binding of kringle 4 is approximated well by prothrombin kringle 1 but with some notable exceptions. The latter transform the site from a non-binding kringle to one which recognizes lysine and other omega-amino-carboxylic acids. The binding site of the observed kringle 4 structure is also compared with one that was modelled from the structure of kringle 1 of prothrombin fragment 1 and NMR observations. Arginine residues of the binding site of a neighbouring molecule make ion pairs with aspartic acid residues in the binding site of another molecule in the kringle 4 structure.
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