Cell wall polysaccharidase activities and growth processes: a possible relationship

In Vigna radiata (L.) Wilczeck hypocotyl, the maximal growth zone is located right under the hook and moves 5 mm lowe exogenous auxin. A good correlation has been obtained between the magnitude of the growth response and the cell wall β 1→3 endoglucanase activities. In cell walls from segments with different growth potentials, the kinetic constants of the β 1→3 endoglucanases are not identical. When the enzymes are rendered soluble, their behaviors become almost similar. These data indicate a relationship between the kinetic behavior of the immobilized enzymes and the structure of their support, i.e. the cell wall organization, which is modified during cell elongation. The possible involvements of these enzymes in some pathways of growth processes are discussed.