Immunochemical Specificity of Lactate Dehydrogenase-X

Abstract

Sperm-producing testes of mammals and some birds contain a unique form of lactate dehydrogenase (EC 1.1.1.27) which is a tetramer composed of C subunits, rather than the A and B subunits of lactate dehydrogenase isozymes 1-5. Immunochemical evidence is presented which confirms the hypothesis that the C subunit is encoded in a separate gene from the A and B polypeptides. The evolutionary relationships of these genes are discussed.