Abstract:

A scorpion gland cDNA library was constructed from the scorpion Liocheles australasiae which was collected from Hainan Province of China. And then an antimicrobial peptide gene, named La39, was screened from the cDNA library. Its mature peptide is composed of 18 amino acids, and its secondary structure is α-helix. Hydrophilic and hydrophobic amino acids are located on the opposite side of the molecule, forming a strong amphoteric topological structure. The results of MICs assay, and hemolytic experiments and growth inhibitory assay showed that the minimum inhibition concentration of La39 for Staphylococcus aureus was 50 μg/ mL, which, however, had no inhibitory activity on Escherichia coli, and had hemolytic activity.

Key words: antimicrobial peptide, Liocheles australasiae, cDNA library, active peptide