| Abstract
| - The gelling characteristics of two vicilin fractions from pea (Pisum sativum L.) were compared overa range of pH and salt conditions after preliminary results showed that despite having equal opportunityto unfold, and expose hydrophobic residues, they had different minimum gelling concentrations (atpH 7.6). Furthermore, at this pH one fraction formed turbid gels and the other formed transparentgels. The fraction that formed transparent gels contained a substantial amount of the 70 kDa α-subunitsof vicilin, and thus it was hypothesized that the highly charged N-terminal extension region on these70 kDa subunits hinders gelation of this vicilin fraction at pH 7.6 and I = 0.2 due to repulsion of thenet negative charge. The experiments designed to test this hypothesis are presented and discussedin this paper and prove that the hypothesis was true, which offers the possibility to control or modifythe gelation behavior of vicilin on the basis of information of its subunit composition. Keywords: Pisum; storage proteins; heterogeneity; N-terminal extension region; aggregation; gelation;turbid and transparent gels
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