Light scattering studies on the reaggregation and deaggregation of bovine alpha-crystallin in the presence of calcium ions.
The concentration dependence of reduced scattering intensity of fractionated bovine lens alpha-crystallin was observed in the presence of various concentrations of calcium ions, using the usual angular light scattering technique. The intensity of scattered light at zero angle per unit concentration of alpha-crystallin increased sharply with increase of the calcium ion concentration, reaching a maximum at about 50-60 mM, and then decreasing rapidly at calcium levels above 60 mM. This indicates that reaggregation and deaggregation of alpha-crystallin occur in the presence of calcium ions. Application of light scattering analysis showed the inverse intensity of the scattered light to have a significant upward curvature with increasing alpha-crystallin concentration. The third virial coefficient determined from this upward curvature was very high at low calcium concentrations, and then decreased monotonously with increase of the calcium ion concentration. It was almost zero over the high concentration of 50 mM Ca2+.
D000818:Animals; D002118:Calcium; D002417:Cattle; D003459:Crystallins; D007700:Kinetics; D008027:Light; D046911:Macromolecular Substances; D008970:Molecular Weight; D011485:Protein Binding; D012542:Scattering, Radiation
D003459:Crystallins; D046911:Macromolecular Substances; D002118:Calcium