Evaluation of peptids screened by ribosome display through antimicrobial activity in vitro

Abstract

Objective To investigate the activity of the peptids that were screened by cell-free ribosome display system and combined with bacterial membrane against bacterium in vitro, and to evaluate the screening system feasibility. Methods The peptid (C13) was synthesized based on the protein structure prediction results that showed C13 with a alpha-helix and good dissolution. In vitro, susceptibilities of C13 and gentamicin sulphate were evaluated against several Gram-positive (Staphylococcus aureus) and Gram-negative bacterium (Escherichia coli, Bacillus typhi), using modified broth microdilution method. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were measured. Results The MIC of C13 against all test bacterium was 400 mg/L. The MBC of C13 against the test bacterium was not detected within the concentration range. Conclusions The peptids C13 screened by cell-free ribosome display system have aitimicrobial activity in some content. However it is necessary for discovering the effective antibacterial peptides to validate by against bacterium experiments. This method of peptids screening by artificial membrane and ribosome display is successful. Key words: Ribosome; Antipeptid; Artificial membrane; Drug sensitive test