Abstract: A fusion protein Resilin\|R5 which was expected to have a superiority of high elasticity and silicon deposition was designed and expressed in Escherichia coli. At the same time， a facile purification method was built to obtain the new fusion protein. Firstly， the recombinant resilin\|r5 gene， which constructed by fusing the diatoms R5 peptide gene sequences to the 3’ end of Drosophila melanogaster resilin gene sequences， was synthesized after a rare codon optimization. Then， the new gene was inserted into the prokaryotic expression vector pET28a. The expression vector was transformed into E. coli BL21（DE3）pLysS strain， and the transformant was cultured in an auto\|induced medium to get resilin\|r5 gene expressed. At last， the His\|tagged recombinant fusion protein was purified by‘salting\|out and heatingmethod and Ni ion column affinity chromatography. The efficient expression of the fusion Resilin\|R5 reached 120 mg per liter culture. A solid foundation was built for characterization and innovative applications of the fusion protein Resilin\|R5 which has high elasticity and silicon deposition ability.

Key words: Resilin\|R5, fusion expression, protein purification