Induction, selection and antibacterial activity of the antibacterial peptides from lepidopteran insect cultured cell lines

Abstract

We induced 3 cell lines that were in vitro cultured from Lepidoptera with heat inactivated Escherichia coli DH_5? to stimulate the antibacterial peptide followed by antibacterial activity assay, induction dynamic research and Tricine sodium dodecyl sulfate-polyacrylamide gel electrophoresis (Tricine SDS-PAGE) experiment. The antibacterial activity of the induced BTI-Tn-5B1 cell line was the highest, and the antibacterial activity increased gradually to the highest level in 16 hours after stimulation. A new antibacterial peptide with a molecular weight of about 8000 Da was preferentially induced in Trichoplusia ni BTI-Tn-5B1 cells in 16 hours after stimulation. Antibacterial activity assays indicated that it had inhibition against Staphylococcus aureus, Escherichia coli K₁₂D₃₁ and Salmonella derby. It has especially strong inhibition against Gram-negative bacteria such as Escherichia coli K₁₂D₃₁ and Salmonella derby.

Keywords

antibacterial peptide / BTI-Tn-5B1 cell line / Tricine SDS-PAGE / antibacterial activity