Abstract: It was to express active recombination SMAP-29 antibacterial peptides by genetic engineering technology. Optimization smap- 29 gene sequences according to Escherichia coli preference codon usage and adding enterokinase recognition sites at N-terminus and stop codon at C-terminus of the target peptide sequence. The DNA sequence was synthesized by chemical technology and inserted into the pET-28a （+）expression vector through the EcoR I and Hind III sites. Recombinant protein was expressed in Escherichia coli BL21（DE3）harboring pET28a-smap29 recombinant vector by IPTG induced, and purified by Ni-NTA affinity chromatography. SMAP-29 peptide was released by enterokinase cleavage of the fusion protein and its antibacterial activity was detected. Results showed SMAP-29 recombinant fusion protein with 6×His tag and enterokinase recognition sites was expressed in inclusion body form, and the fusion protein can by purified by Ni-NTA affinity chromatography. SMAP-29 peptide was released from fusion protein by enterokinase cleavaging. The minimum inhibition concentration（MIC） of SMAP-29 against E. coli, S. aureus and C. albicans was 10, 20 and 40 μmol/L, respectively.

Key words: Antimicrobial peptide, SMAP-29, Prokaryotic expression, Antimicrobial activity