Developmental ‘Changes in Activities of Several Enzymes Involved in Glycolysis and TCA Cycle during the Pupal Period of Bombyx mori

In order to elucidate metabolic regulation with regard to carbohydrates and lipids during metamorphosis of Bombyx mori, eight enzymes related to glycolysis and TCA cycle were measured for their levels of activity during the period from the day of pupal ecdysis to 2 days after adult emergence, by use of crude extract from the whole bodies of the insect. The resulting patterns could be grossly divided into two groups. Glucose-B-phosphate dehydrogenase, NADP-specific isocitrate dehydrogenase, malic enzyme, hexokinase and pyruvate kinase were characterized by their apparent high activity levels during larval-pupal development followed by low levels at emergence. On the contrary, aconitase, NAD-specific isocitrate dehydrogenase and malate dehydrogenase were characterized by their apparent low levels during pupal period and by an abrupt increase in activity before emergence. The roles of these enzymes in metamorphosis are briefly discussed