Genetic Variation and Immunochemical Properties of L-Malate : NAD+ Oxidoreductase Isozymes in the Bandicoot, Isoodon macrourus.

Abstract

A genetic polymorphism for the soluble isozyme (MDH-A2) of malate dehydrogenase (L-malate : NAD+ oxidoreductase; EC 1.1.1.37) was found in a Townsville-Inkerman population of short-nosed bandicoots, 1. macrourus. The enzyme seems to be inherited in a normal autosomal codominant manner. The gene frequencies for the MDH-A and MDH-A' alleles were O' 82 and 0·18 respectively. The genotypic frequencies indicated that the population was in Hardy-Weinberg equilibrium. None of 22 pouch young from seven litters expressed a phenotype inconsistent with its mother's genotype, assuming autosomal co dominance. Other populations of I. macrourus and of the long-nosed bandicoot (Perameles nasuta) exhibited only the MDH-A allele. Homologous relationships of bandicoot MDH-A2 and MDH-B2 isozymes to those of other vertebrates were established by immunochemical studies.