Expression of biologically active insect-derived antibacterial peptide, defensin, in yeast = 효모에서 활성형의 곤충유래 항균펩티드 defensin의 발현

Abstract

As a biological model system for the production of an active antibacterial peptide, we have attempted the expression and secretion of insect defensin in Saccharomyces cerevisiae. Nucleotide sequences encoding mature defensin composed of 40 amino acids were fused in frame with promoter and signal sequence of Saccharomyces diastaticus glucoamylase, and mating factor α1[MFα1] prosequence. The host strain, S. cerevisiae 2805 was transformed with the resulting plasmid, pSMF11. The secretion of functional defensin was confirmed by growth inhibition zone assay using Micrococcus luteus as a test organism. Insect defensin was secreted to the culture supernatant in biologically active form by glucoamylase signal sequence and mating factor α1 prosequence. Most of antibacterial activity was detected in the culture supernatant. Defensin was also active against Staphylococcus aureus and Listeria monocytogenes.