Cereal Chem 42:44 - 53.  |  VIEW ARTICLE

UDPG-Alpha-Glucan Glucosyltransferase and Amylose Content of Some Starches During Their Development and Under Various External Conditions.

N. P. Badenhuizen and K. R. Chandorkar. Copyright 1965 by the American Association of Cereal Chemists, Inc. 

Low activity of UDPG-alpha-glucan glucosyltransferase in waxy corn varieties had suggested that this enzyme might be connected with the presence of amylose in most starches. Starches varying in amylose content were isolated for the determination of glucosyltransferase activity. Use was made of the natural increase in amylose content of starch during its development in corn endosperm or tobacco leaves; in other cases, changes in amylose percentage were induced by varying the environmental conditions (light, temperature) during growth. The results obtained so far do not provide evidence for a direct proportional relationship between glucosyltransferase activity and amylose content, although in some cases both decrease or increase simultaneously. The results suggest that plastid proteins may be important in determining the final composition of the starch granule.