The compact domain conformation of human Glu-plasminogen in solution.
A complete understanding of the accelerating mechanisms of plasminogen activation and fibrinolysis necessarily requires structural information on the conformational forms of plasminogen. Given the absence of high-resolution structural data on plasminogen the use of lower resolution approaches has been adopted. Two such approaches have previously indicated a compact conformation of Glu-plasminogen (Tranqui, L., Prandini, M., and Chapel, A. (1979) Biol. Cellulaire, 34, 39-42; Bányai, L. and Patthy, L. (1985) Biochim. Biophys. Acta, 832, 224-227) whereas a third has suggested a fairly extended conformation (Mangel, W., Lin, B. and Ramakrishnan, V. (1990) Science, 248, 69-73). Native Glu-plasminogen has been investigated using small-angle X-ray scattering (SAXS) experiments. It is concluded that this molecule in solution is compact (radius of gyration, RG 3.05 +/- 0.02 nm and maximum intramolecular distance, Im 9.1 +/- 0.3 nm) and that the data are consistent with the right-handed spiral structure observed using electron microscopy by Tranqui et al. (1979). A spiral structure of native plasminogen would have important implications for the conformational response of plasminogen to fibrin and concomitant stimulation of plasminogen activation.
Ponting
C P
CP
Laboratory of Molecular Biophysics, University of Oxford, Department of Biochemistry, UK.
Holland
S K
SK
Cederholm-Williams
S A
SA
Marshall
J M
JM
Brown
A J
AJ
Spraggon
G
G
Blake
C C
CC
D003198:Computer Simulation; D006801:Humans; D008958:Models, Molecular; D010958:Plasminogen / Q000737:chemistry*; D011487:Protein Conformation; D012542:Scattering, Radiation; D012996:Solutions
D012996:Solutions; D010958:Plasminogen