The Nucleotide and Deduced Amino-Acid Sequences of a cDNA Encoding Lactate Dehydrogenase from Caenorhabditis elegans: The Evolutionary Relationships of Lactate Dehydrogenases from Mammals, Birds, Amphibian, Fish, Nematode, Plants, Bacteria, Mycoplasma, and Plasmodium

The nucleotide and deduced amino-acid sequences of a cDNA encoding L-lactate dehydrogenase (LDH) from nematode, Caenorhabditis elegans, were reported. This first invertebrate LDH sequence of 333 amino acids, including the initiation methionine, exhibits 63% identity with that of the most primitive vertebrate lamprey. The evolutionary relationships among 36 LDH isozymes from mammals, birds, amphibian, fish, nematode, plants, bacteria, mycoplasma and plasmodium were analyzed. The invertebrate nematode LDH is evolutionarily positioned between plant LDH and mammalian testicular LDH-C isozymes. The mammalian LDH-C isozyme appears to have arisen after the invertebrate LDH, but prior to the divergence of vertebrate LDH-A (muscle) and LDH-B (heart) isozymes as described previously.