Dynamic light scattering studies on hydrodynamic properties of fibrinogen-fibronectin complex.
A high molecular weight 'cryogel' was obtained as insoluble complexes by cold incubation at near-freezing temperatures from heparinized plasma of patients with rheumatoid arthritis. After the cryogel was solubilized at 37 degrees C, 1:1 complex of fibrinogen and fibronectin was purified at room temperature by affinity chromatography on a gelatin-Sepharose 4B. Hydrodynamic properties of the complex were investigated as a function of temperature and NaCl concentration using a dynamic light scattering. The diffusion coefficients of the complex at 20 degrees C decreased with increasing of NaCl concentration as free fibronectin. The complex appears to be a more compact form at low ionic concentration, which is associated with conformational changes of fibronectin. The diffusion coefficient of the complex at 20 degrees C in 0.05 M TrisHCl(pII7.4) containing 0.5 M NaCl was estimated as 8.5 x 10(-8) cm2s-1. The complex did not dissociate over the temperature range from 20 to 37 degrees C. The diffusion coefficients of the complex decreased significantly at 12 degrees C and 40 degrees C. The thermal denaturation of fibrinogen molecule in the complex was observed at 40 degrees C. The CONTIN analysis of the light scattering data showed that the complex associated to form higher aggregates at 15 degrees C, but not at near-freezing temperature. The equilibrium between the complex and higher aggregates appeared reversible.
Nagamatsu
K
K
Department of Materials Science and Technology, Yamaguchi College, Japan.
Komori
M
M
Kuroda
S
S
Tanaka
K
K
D004058:Diffusion; D005340:Fibrinogen / Q000737:chemistry*; D005353:Fibronectins / Q000737:chemistry*; D006801:Humans; D008027:Light; D009994:Osmolar Concentration; D012542:Scattering, Radiation; D013696:Temperature
D005353:Fibronectins; D005340:Fibrinogen