Expression of mature peptide of human bone morphogenetic protein-7 in escherichia coli

Objective: To study the expression of the mature peptide of human bone morphogenetic protein-7(hBMP-7) in escherichia coli.Methods:The cDNA fragment encoding the mature peptide of hBMP-7,with start codon and two tandem stop codons,was inserted into expression vector pDH in which foreign gene was controlled by P_RP_L promoters.The recombinant plasmid pDHB-7m was transformed into E.coli DH5α and induced at 42 ℃ to express the encoded protein.Results:After induction,a new anticipated 16 ku protein band appeared on SDS-PAGE gel and amounted to 20% to 25% of total bacterial protein.The expressed product existed in a form of inclusion body.After being partially purified and refolded,rhBMP-7m could heterotopically induce the formation of cartilage and bone tissue.Conclusion:The mature peptide of hBMP-7 has been successfully expressed in E.coli,and it lays the foundation for the study of biological activity and clinical practice.