Kinetic modeling of the thermal aggregation of patatin

A kinetic model of the thermal aggregation of patatin is presented based on chromatographic analysis of the proportions of nonaggregated and aggregate d patatin. It was observed that the decrease of the amount of nonaggregated patatin proceeded initially quickly and was followed by slower aggregation at longer incubation times. It was shown that this behavior was not due to heterogeneity of the starting material. It was noted that overestimation o f the amount of native molecules after a heat treatment, caused by refoldin g of the unfolded protein during the cooling step prior to the analysis, wa s significant and could not be neglected. Hence, corrections based on infor mation on the structural properties of patatin were applied. Taking this in to account, a model was proposed consisting of a first-order formation of r eactive particles, followed by a second-order aggregation reaction. This mo del described the thermal aggregation of patatin rather accurately and was confirmed by experiments at various protein concentrations.