Quantitative immunochemical and electrophoretic comparisons of glycerophosphate dehydrogenases in several insects

Abstract

An immunochemical method, micro-complement fixation, has been used to compare quantitatively DPN +-dependent glycerophosphate dehydrogenases (EC 1.1.1.8) of various insects. Rabbit antibodies directed against pure honeybee glycerophosphate dehydrogenase were prepared, and the cross-reaction with extracts of other insects measured. The order of decreasing cross-reaction is: honeybee, bumblebee, robust mining bee, leaf-cutting bee, sphecoid wasp, yellow jacket, syrphid, and flesh fly; this is the same as the classical taxonomic order. Several other insects apart from the Hymenoptera show no detectable cross-reaction; the enzymes from six honeybee races and the three honeybee social orders possess identical immunological properties. The specific activity of glycerophosphate dehydrogenase in honeybee thoracic muscle increases fivefold during the week following adult emergence. The immunological properties of the enzyme are identical in the newly emerged and 6-day-old bees. Thus the change in enzyme activity is apparently due to an increase in the number of enzyme molecules. Electrophoretograms show that most of the insects studied here have more than one band with glycerophosphate dehydrogenase activity. There is, however, no obvious taxonomic relationship between the electrophoretic patterns of these insects.