An antimicrobial poly-β-peptide(β-amino acid polymer)was synthesized and characterized by nuclear magnetic resonance and gel permeation chromatography to give the number-average molecular weight of the polymer.The antibacterial activity of this poly-β-peptide against Gram positive bacteria,including multiple drug-resistant strains,was evaluated by its minimum inhibitory concentration(MIC).The MIC test showed that this poly-β-peptide had potent antibacterial activity(MIC value in the range of3.13-12.5μg/mL)a...