Nicotinamide–Adenine Dinucleotide-linked Form of Lactic Dehydrogenase of the Symbionts and Fat Bodies of a Cockroach

Abstract

ALTHOUGH lactic dehydrogenase is an enzyme which is to be found in the tissues of most animals, it is present in only low concentrations in those of insects. When Ludwig and Barsa¹ investigated the nicotinamide–adenine dinucleotide (NAD)-linked form of the enzyme in homogenates of the mealworm Tenebrio molitor they found it to be present in low concentrations, as also did Prota² in the haemolymph of the same insect. Since Pierre^3–5 demonstrated that the symbionts and fat bodies of the cockroach Leucophaea maderae are the source of enzyme systems, the purpose of the present investigation was to determine whether or not the NAD-linked form of lactic dehydrogenase could be detected in the symbionts or the fat bodies of the same cockroach.