title: The influence of calcium ions on the conformation of fibrinogen fragment D: the use of chemical cross-linking agents.
abstract: Fibrinogen fragment D prepared in the presence of calcium ions (fragment D[Ca++]) shows qualitatively similar cross-linking patterns with dimethyl suberimidate, dimethyl adipimidate and tetranitromethane. Fragment D prepared in the presence of EDTA (fragment D[EDTA]) gives a consistently different pattern with these reagents. In the case of fragment D[EDTA] there is much more intermolecular cross-linking suggesting that the loss of the C-terminus of the gamma-chain remnant results in fragment D adopting a more open conformation. Neither the addition of 2M urea nor EDTA to fragment D[Ca++] alters its cross-linking pattern suggesting that the proposed conformational change follows cleavage of a plasmin susceptible bond which is normally protected by the presence of calcium ions.
mesh_terms: D002118:Calcium / Q000494:pharmacology* / Q000502:physiology; D055598:Chemical Phenomena; D002621:Chemistry; D003432:Cross-Linking Reagents / Q000494:pharmacology*; D004119:Dimethyl Adipimidate / Q000494:pharmacology; D004120:Dimethyl Suberimidate / Q000494:pharmacology; D004492:Edetic Acid / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D005338:Fibrin Fibrinogen Degradation Products; D005340:Fibrinogen / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D011487:Protein Conformation / Q000187:drug effects*; D013774:Tetranitromethane / Q000494:pharmacology
chemical_list: D003432:Cross-Linking Reagents; D005338:Fibrin Fibrinogen Degradation Products; C015214:fibrinogen D fragment; D004119:Dimethyl Adipimidate; D004120:Dimethyl Suberimidate; D005340:Fibrinogen; D004492:Edetic Acid; D013774:Tetranitromethane; D002118:Calcium