关键词: 光滑鳖甲, 抗菌肽, 原核表达, 蛋白纯化, 抗菌活性

Abstract: 【Aim】 To explore the optimal prokaryotic expression conditions and study the antimicrobial activity of a novel glycine-rich antimicrobial peptide ApAMP1015 from Anatolica polita borealis.【Methods】 The cDNA and deduced amino acid sequences of ApAMP1015 were analyzed by bioinformatics methods. Prokaryotic expression technology was used to express fusion protein TrxA-ApAMP1015. The fusion protein TrxA-ApAMP1015 was verified by Western blot, and purified with affinity chromatography. Inhibition zone experiment was made to assay the antibacterial activity of ApAMP1015. 【Results】 An antimicrobial peptide gene ApAMP1015 was cloned from A. polita borealis. ApAMP1015 has the opening reading frame of 387 bp and encodes a 128-amino-acid peptide consisting of a signal peptide of 19 amino acids and a mature peptide of 75 amino acids. Homology analysis showed that ApAMP1015 is a member of coleoptericins. The prokaryotic expression vector pET-32a-ApAMP1015  was successfully constructed and the recombinant protein expressed in Escherichia coli BL21(DE3) was verified by Western blot. The0.1 mmol/L IPTG induced a higher level of expression of recombinant protein in the supernatant in the culture condition of 25℃ and 150 r/min. The inhibition zone experiment showed that ApAMP1015 exhibited the antibacterial activity against E. coli. 【Conclusion】 The full-length cDNA of ApAMP1015 was cloned from A. polita borealis. The optimal prokaryotic expression conditions were determined. ApAMP1015 can inhibit the growth of E. coli. This study lays the foundation for promoting the application and further study of ApAMP1015 from A. polita borealis.

Key words: Anatolica polita, antimicrobial peptide, prokaryotic expression, protein purification, antibacterial activity