In silico studies of genes encoding enzymes from LDH/MDH superfamily in different organisms, we found that the aminoacid sequence of the channel catfish Ictalurus punctatus,encoded by the Mdh1 gene, is significantly different from the products of the Mdh1 genes other animals. The detected sequence has a conservative domain specified for the enzymes of the LDH/MDH superfamily, however, it has no significant similarity to any enzyme of this superfamily. Thus, we detected a gene encoding a new enzyme from the LDH/MDH superfamily, which we designated as unLdh/Mdh (unknown Ldh/Mdh).
malate dehydrogenase, lactate dehydrogenase, LDH, MDH, metabolism
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