Kinetic analysis of bovine alpha-crystallin reaggregation in the presence of calcium ions.
The kinetics of alpha-crystallin reaggregation in the presence of calcium ions were investigated by monitoring changes in optical density at 320 nm. alpha-Crystallin showed a critical concentration. In the initial stages, reaggregation and deaggregation of alpha-crystallin may be essentially fully reversible in the presence of high levels of calcium ions. The initial rate of reaggregation was strongly calcium ion-dependent. The kinetics of alpha-crystallin reaggregation revealed a pseudo-first order time dependence. This is most easily explained by postulating very rapid formation of the initial complex for alpha-crystallin reaggregation (nucleation). These studies indicate that reaggregation of alpha-crystallin occurs by a pathway involving a nucleation phase followed by an elongation phase, that the formation of the small active initiator, presumably alpha-crystallin dimer or some species formed from it (i.e., intermediate high molecular weight component) is very fast, and that the growth of these active initiators is biphasic.
D000818:Animals; D002118:Calcium / Q000494:pharmacology*; D002417:Cattle; D003459:Crystallins / Q000378:metabolism*; D007700:Kinetics; D009391:Nephelometry and Turbidimetry
D003459:Crystallins; D002118:Calcium