title: Predicted secondary structure of bovine prothrombin fragment 1 and related proteins in different environments by circular dichroism spectroscopy.
abstract: Circular dichroism spectroscopy was used to investigate the structure of bovine prothrombin fragment 1 (BF1) and related proteins in several environments. The conformational change induced in BF1 by the addition of Mg[II] ions was found to be different from that induced by Ca[II] or Sr[II]. The Ca[II] and Sr[II] conformations appear to differ only slightly from the apo-metal conformation. The conformation of the 1-45 fragment of prothrombin, however, is markedly different than the conformation of the same fragment in the presence of either Ca[II] of Mg[II]; both of the latter structures differ substantially from one another. The presence of phospholipids has almost no effect on the structure of either BF1 or the 1-45 fragment; in the presence of both phospholipids and Ca[II] a structural change is seen for the 1-45 fragment but not BF1 (relative to the protein alone). The addition of phospholipids to the Mg[II]/BF1 structure did not induce a CD-detectable conformational change, while the addition of phospholipids to the Ca[II]/BF1 or Sr[II]/BF1 structures induced a change to a conformation similar in secondary structure composition to the relative apometal structures.
authors.affiliation: Department of Chemistry, University of North Carolina, Chapel Hill.
authors.forename: L M
authors.initials: LM
authors.lastname: Balbes
authors.forename: L G
authors.initials: LG
authors.lastname: Pedersen
authors.forename: R G
authors.initials: RG
authors.lastname: Hiskey
mesh_terms: D000818:Animals; D002413:Cations, Divalent / Q000494:pharmacology; D002417:Cattle; D002942:Circular Dichroism; D010446:Peptide Fragments / Q000138:chemical synthesis* / Q000737:chemistry / Q000187:drug effects; D010455:Peptides / Q000737:chemistry / Q000187:drug effects; D010743:Phospholipids / Q000494:pharmacology; D011487:Protein Conformation / Q000187:drug effects; D011498:Protein Precursors / Q000138:chemical synthesis* / Q000187:drug effects; D017433:Protein Structure, Secondary / Q000187:drug effects; D011516:Prothrombin / Q000138:chemical synthesis* / Q000187:drug effects; D014961:X-Ray Diffraction
chemical_list: D002413:Cations, Divalent; D010446:Peptide Fragments; D010455:Peptides; D010743:Phospholipids; D011498:Protein Precursors; C029733:prothrombin fragment 1; D011516:Prothrombin