A Developmental Study of D-Glyceric Acid Dehydrogenase

Since the mere presence of an enzyme in a tissue does not establish a physiological role, further data are needed in order to elucidate the possible metabolic function of this enzyme. As an aid in obtaining such information, the developmental pattern of this dehydrogenase was studied. The previous investigation (13) had shown that although D-glyceric acid dehydrogenase is widely distributed in the tissues of various higher plants, the enzyme is present in a particularly high concentration in green leaves. This localization has been substantiated by following the pattern of the increase in the enzymatic activity upon germination. Another DPN-dependent enzyme, glyoxylic acid reductase (17), was studied for comparison. Peas and wheat were selected as representative plants because of their ease of growth under laboratory conditions.