Predicted secondary structure of bovine prothrombin fragment 1 and related proteins in different environments by circular dichroism spectroscopy

Int J Pept Protein Res. 1992 Aug;40(2):127-33. doi: 10.1111/j.1399-3011.1992.tb01460.x.


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.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Cations, Divalent / pharmacology
  • Cattle
  • Circular Dichroism
  • Peptide Fragments / chemical synthesis*
  • Peptide Fragments / chemistry
  • Peptide Fragments / drug effects
  • Peptides / chemistry
  • Peptides / drug effects
  • Phospholipids / pharmacology
  • Protein Conformation / drug effects
  • Protein Precursors / chemical synthesis*
  • Protein Precursors / drug effects
  • Protein Structure, Secondary / drug effects
  • Prothrombin / chemical synthesis*
  • Prothrombin / drug effects
  • X-Ray Diffraction


  • Cations, Divalent
  • Peptide Fragments
  • Peptides
  • Phospholipids
  • Protein Precursors
  • prothrombin fragment 1
  • Prothrombin