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Objective:To identify full length cDNA sequence of lactate dehydrogenase(LDH) from adultEchinococcus granulosus (E. granulosus) and to predict the structure and function of its encoding protein using bioinformatics methods.Methods: With the help ofNCBI, EMBI, Expasy and other online sites, the open reading frame (ORF), conserved domain, physical and chemical parameters, signal peptide, epitope, topological structures of the protein sequences were predicted and a homology tertiary structure model was created; VectorNTI software was used for sequence alignment, phylogenetic tree construction and tertiary structure prediction. Results: The target sequence was1 233 bp length with a996 bp biggestORFencoding331 amino acids protein with typicalL-LDH conserved domain. It was confirmed as full length cDNA of LDH fromE. granulosus and named asEgLDH (GenBank accession number:HM748917). The predicted molecular weight and isoelectric point of the deduced protein were3 5516.2Da and6.32 respectively. Compared withLDHs fromTaenia solium, Taenia saginata asiatica, Spirometra erinaceieuropaei, Schistosoma japonicum, Clonorchis sinensis and human, it showed similarity of 86%, 85%, 55%, 58%, 58% and 53%, respectively. EgLDH contained3putative transmembrane regions and4 major epitopes (54aa-59aa,81aa-87aa,97aa-102aa,307aa-313aa), the latter were significant different from the corresponding regions of humanLDH. In addition, someNAD and substrate binding sites located on epitopes54aa-59aa and97aa-102aa, respectively. Tertiary structure prediction showed that3 key catalytic residues105R, 165D and192H forming a catalytic center near the epitope97aa-102aa, mostNAD and substrate binding sites located around the center.Conclusions: The full length cDNA sequences of EgLDH were identified. It encoded a putative transmembrane protein which might be an ideal target molecule for vaccine and drugs.