Dextranase Activity in Coleoptiles of Avena

An enzyme activity similar to that of dextranase is associated with coleoptiles of Avena sativa. When subjected to purified dextranase, both the pure natural dextran and the cell walls of the Avena coleoptiles yield isomaltose and isomaltotriose. Thus, the cell walls contain dextrans or dextran-like compounds. Coleoptiles with low auxin content have a lower dextranase activity than coleoptiles with high auxin content. The enzyme activity is therefore in some way sensitive to the hormone.