Expressing Of Novel Human Calcitonin Gene In E.coli

Calcitonin is one of important peptide regulatory hormones, playds important roles in metabolism of calcium and phosphorous and involves in development and differentiation of bone.The encoding fragments of novel hCT gene (Proline codon were displaced by Glutamin codon )was amplified by means of PCR ,and was insert into fusion expressive vector pET42a. The recombinant expressive vector pET42a/hCT* was transformed into E.coli BL21(DE3)plysS. Induced with IPTG , the cells produced a protein with a molecular weight of about 34 kD on SDS-PAGE gel. The protein has the immunogenicity of human calcitonin verified by Western Blot analysis .After optimization of condition, fusion protein was concentrated by ultrafiltration and cleaved by factor X a, then recombinant novel hCT was obtained. Finally, we confirmed that the novel hCT has the hypocalcemic bioactivity in rats.