Demonstration of Aldolase Types in Photosynthetic Organisms'

or ethylenediamune tetrancetate (Type I). Dark grown Euglena and Chlorella have aldolases inhibited by p-ohloromercuribenzoa.te and ethylenediamine tetraacetate but stimulated by K4 (Type II). The red alga, Chondrus, and the golden-brown alga, Ochromonas, appear to possess both types. Bean, pea, and spinach seeds and the leaves and cotyledons of etiolated bean seedlin4s oontain a p-diloromercuribenzoate insensitive, apparently non-sulfhydryl variant of Type I. Senitivity of leaf aldolase to p-chloromercuribenzoate oocurs in etiolated bean seedlings only after an extended period of illumination. Type II aldolase activity in cell-free extraots of 4 blue-green algae has been demonstrated.