Determination of the effect of r and rb mutations on the structure of amylose and amylopectin in pea (Pisum sativum L)

The structure of starch from pea lines near-isogenic except for mutation at the r and rb loci was compared with that of the wild-type. The isolated starch polysaccharides were fractionated by size exclusion chromatography, and the constituent chain profile of the branched amylopectin components examined. A mutation at the rb locus had little effect on starch structure and composition. A mutation at the r locus (a genetic lesion affecting the activity of an isoform of starch branching enzyme) resulted in an increase in the amylose content of the starch and a change in the structure of amylopectin. Copyright (C) 1996 Elsevier Science Ltd