529 POSTER Anti-tumor efficacy of the integrin-targeted immunoconjugate IMGN388 in preclinical models

Abstract

Developing novel antibiotics is urgently needed with emergency of drug resistance. Vancomycin, the last resort for intractable Gram-positive bacterial infections, is ineffective against Gram-negative bacteria and vancomycin resistant bacteria. Herein, we report a series of novel vancomycin derivatives carrying LPS binding peptides, vancomycin-LPS binding peptide conjugates (VPCs). The LPS binding peptides were conjugated onto 4 sites of vancomycin via CuAAC or maleimide- sulfydryl addition, and the formed VPCs were screened against VISA/VRE and Gram-negative strains. VPCs exhibited enhanced activity against vancomycin resistant bacteria and obtained the activity against Gram-negative bacteria in vitro, providing a novel strategy for vancomycin modification and glycopeptide antibiotics synthesis.