| Abstract
| - Thermal denaturation and aggregation of βL-crystallin from bovine lens have been studiedusing differential scanning calorimetry (DSC) and dynamic light scattering (DLS). According to the DLSdata, the distribution of the βL-crystallin aggregates by their hydrodynamic radius (Rh) remains monomodalto the point of precipitating aggregates (sodium phosphate, pH 6.8; 100 mM NaCl; 60 °C). The size ofthe start aggregates (Rh,0) and duration of the latent stage (t0) leading to the formation of the start aggregateshave been determined from the light scattering intensity versus the hydrodynamic radius plots and thedependences of Rh on time. The Rh,0 value remains constant at variation of the βL-crystallin concentration,whereas the t0 value increases with diminishing βL-crystallin concentration. The suppression of βL-crystallinaggregation by α-crystallin is connected with the decrease in the Rh,0 value and increase in the t0 value.In the presence of α-crystallin the aggregate population is split into two components. The first componentis represented by stable aggregates whose size remains constant in time. The aggregates of the other kindgrow until they reach the size characteristic of aggregates prone to precipitation. The DSC data show thatα-crystallin has no appreciable influence on thermal denaturation of βL-crystallin.
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