Characterisation of three wheat proteins found in chloroform‐methanol extracts of flour

Abstract

Abstract Three wheat proteins, CM1, CM2 and CM3 constituting in total more than 1% of flour proteins, have been isolated from chloroform—methanol (2:1 v/v) extracts of flour. CM1 and 2 have single chains with m.w. of 13 000 and isoleucine as the C‐terminal amino acid. They appear to be closely related even in amino acid sequence as judged from fingerprints. All three proteins are soluble in chloroform—methanol after freeing from lipid, but only moderately so in water. CM3 becomes insoluble after reduction of SS bonds due to aggregation of the reduced poly‐peptide chains by secondary forces. It differs appreciably from CM1 and 2 in sequence and has C‐terminal leucine and a m.w. of 15 000. The mobilities of CM2 and 3 at pH 3.2 are very close to ALB 13A and ALB 13B, respectively, and the albumins found in electrophoretic patterns of crude gliadin preparations do in fact represent mixtures of both classes.