Prediction of three-dimensional structure of plant lectins from the domains of concanavalin A.

The circularly permuted sequence homology that relates concanavalin A to the other leguminous plant lectins can be explained by an evolutionary model that requires three exons. The identification of these potential exons from the amino acid sequence data allows the prediction of three domains in the lectin structure. The predicted domains are reasonable, functional and structural units in concanavalin A, demonstrating the correspondence of exons and domains. In addition, slight modifications to the three-dimensional structure of concanavalin A produced a model which was consistent with the sequence data for the other plant lectins.