Species and varietal differences in the proteins of rapeseed

Two proteins, previously described by the authors as BI (S020, buffer 12 S) and AIVS (S020, w 1.7 S) have been isolated from eight varieties of rapeseed belonging to Brassica campestris L. and Brassica napus L. species. These proteins have similar chromatographic and electrophoretic characteristics but differ in amino acid composition, particularly with regard to the sulfur-containing amino acids. One of the rapeseed samples was obtained from plants grown on sulfur-deficient soil. The sulfur deficiency produced, in the mature seed, a much reduced protein content and appeared to affect the structure of the protein BI.