Abstract: 　Objective To sequence the cloned gene Sj338 and to identify the encoded protein and its antigen epitopes.Methods The Sj338 gene fragment obtained from adult S. japonicum cDNA library amplified by PCR method was subcloned into pGEM T vector for sequencing. The sequence of nucleotides and the characteristics of the encoded protein were analyzed by DNASIS Program and Goldkey DNA and Protein Analytical Program, and then the homology of the amino acid sequence was searched on the BLAST net.Results The cloned rSj338 gene was demonstrated to be 487 bp containing one 459bp ORF, encoding a protein consisted of 153 amino acids with a molecular weight of 17 6 kDa. The amino acid sequence of the recombinant protein rSj338 shared 46% identity with that of the corresponding part of human mitochondrial import receptor and 44% identity with that of the Rattus sp. mitochondrial precursor receptor. The possible antigen epitopes were predicted within the peptide fragments of 26-32 aa, 37-46 aa and 147-151 aa.Conclusion The protein encoded by rSj338 gene fragment might be the mitochondria related protein of Schistosoma japonicum .

Key words: Schistosoma japonicum, mitochondria, recombinant protein, sequence analysis, mithochondria related protein