Albumins and globulins in developing maize grains.

ABSTRACT

Quantitative and qualitative (amino acid composition) changes of albumins and globulins in developing grain of normal and opaque-2 (o2) maizes were examined in proteins extracted sequentially with water and 0.5 M NaCl, and isolated by salting out with trichloroacetic acid. The amount of albumins per grain reached a maximum at mid-development the declined. Globulins, virtually absent in very young grain, increased in level until maturity. The variations were more marked for o2 than normal maize. Amino acid compositions changed little with development. The selectivity and exhaustiveness of sequential extraction, and the physiological role of albumins and globulins in grain are discussed.