title: Characterization of an extremely large, ligand-induced conformational change in plasminogen.
abstract: Native human plasminogen has a radius of gyration of 39 angstroms. Upon occupation of a weak lysine binding site, the radius of gyration increases to 56 angstroms, an extremely large ligand-induced conformational change. There are no intermediate conformational states between the closed and open form. The conformational chang is not accompanied by a change in secondary structure, hence the closed conformation is formed by interaction between domains that is abolished upon conversion to the open form. This reversible change in conformation, in which the shape of the protein changes from that best described by a prolate ellipsoid to a flexible structure best described by a Debye random coil, is physiologically relevant because a weak lysine binding site regulates the activation of plasminogen.
authors.affiliation: Biology Department, Brookhaven National Laboratory, Upton, NY 11973.
authors.forename: W F
authors.initials: WF
authors.lastname: Mangel
authors.forename: B H
authors.initials: BH
authors.lastname: Lin
authors.forename: V
authors.initials: V
authors.lastname: Ramakrishnan
mesh_terms: D015119:Aminocaproic Acid / Q000378:metabolism / Q000494:pharmacology; D001665:Binding Sites; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D002942:Circular Dichroism; D003903:Deuterium; D006801:Humans; D008239:Lysine / Q000378:metabolism; D009502:Neutrons; D010958:Plasminogen / Q000378:metabolism; D010960:Plasminogen Activators / Q000494:pharmacology; D011487:Protein Conformation / Q000187:drug effects; D012542:Scattering, Radiation; D014568:Urokinase-Type Plasminogen Activator / Q000494:pharmacology; D014867:Water
chemical_list: D014867:Water; D010958:Plasminogen; D003903:Deuterium; D010960:Plasminogen Activators; D014568:Urokinase-Type Plasminogen Activator; D008239:Lysine; D015119:Aminocaproic Acid