Binding of Enzymes to Avena Coleoptile Cell Walls

It has been shown that the auxin, indoleacetic acid (IAA), exerts a marked influence on the pectic metabolism in growing cell walls of the Avena coleoptile (12). The methyl ester group in pectic substances is known to be derived, in part at least, from the methyl group of methionine (21, 22). Through the use of methionine-C^(14)H_3, it was shown that IAA markedly increases the rate of formation of the methyl groups in the cell wall pectic material without detectably changing the degree to which the pectic substances are esterified (12).