Abstract
Rabbit antisera against crucian carp glucose 6-phosphate dehydrogenase were prepared and their relative inhibition potencies were examined against glucose 6-phosphate Table 2. Michaelis constants of G6PD from various species dehydrogenases from 23 species of teleosts, 5 species of other vertebrates and 8 species of invertebrates. The results demonstrated that the immunological relatedness of teleosts expressed as the relative inhibition potencies of antibody against the enzymes is consistent with the phyletic relationships of teleosts depicted by Greenwood et al. (1966); i.e., the inhibition potencies were: carp, 0.78; dace, 0.69; loaches, 0.38; three species of salmoni-formes, 0.19; eels 0.08.
The inhibition potencies of vertebrates other than teleosts and of invertebrates ranged from 0.0008 to 0.0012, and 0 to 0.0004, respectively. Ascarid and planarian enzymes were not inhibited by any antiserum tested. Electrophoretic examination of the mixture of these enzymes and antiboby revealed, however, that the enzymes do possess at least one antigenic determinant common to crucian carp enzyme. No immunological similarity was found between yeast and crucian carp glucose 6-phosphate dehydrogenases and between glucose 6-phosphate dehydrogenase and hexose 6-phosphate dehydrogenase of crucian carp.
