GLUCANASE ACTIVITY IN COLEOPTILES OF AVENA

The presence of five different β-glucanases has been investigated in coleoptiles of Avena with the use of specific substrates. A high activity of β-1,3-glucanase is found associated with the coleoptiles. With regard to β-1,4-glucanase activity a strong activity of exo-cellulase which splits glucose (or cellobiose) from the end of the cellulose chain, and which was determined by the glucose formed, is definitely present in all cases investigated. The activity of endo-cellulase which causes random chain breakage and was determined by the CMC viscosity method is much less pronounced or practically lacking. β-Glucosidase activity, as determined by the splitting of cellobiose, is present. β-1,6-Glucanase activity is present, but β-1,2-glucanase activity is absent. Coleoptile cell walls can serve as substrates for purified preparations of at least the first three of these enzymes. Since the enzymes are associated with the cell wall fraction of homogenized coleoptiles, this may explain the capacity for autolysis of the cell wall material. Experiments with digitonin-treated pellets suggest that the enzymes are present in particulate form. © 1969.