Abstract: The present disclosure provides a pH-sensitive membranolytic polymer material and a preparation method and application thereof. The pH-sensitive membranolytic polymer material has the structure shown in Formula (I). At normal physiological pH, the polymer material is hydrophobic neutral, and can be self-assembled into PEG coated nanoparticles with weak interaction with cell membrane; when the pH decreases, the polymer material can be protonated to form an amphiphilic structure consisting of hydrophobic domain and cationic domain, which has strong interaction with the cell membrane and strong membranolytic activity, so the polymer material can kill tumor cells or bacteria efficiently and selectively.

Abstract: The disclosure provides a class of pH-sensitive, helix/random conformation switchable antimicrobial polypeptide (HRS-AMP) compositions as a single agent to selectively kill bacteria (e.g., H. pylori) under acidic condition in the stomach with diminished bacterial resistance compared to currently used antibiotics. Methods of treating bacterial infections in the stomach are also provided.

Abstract: The invention provides antimicrobial polypeptides (AMPs) with high radial amphiphilicity. Unlike typical AMPs characterized by facial amphiphilicity or biomimetic antimicrobial polymers with randomly distributed charged and hydrophobic groups, these new AMPs are homo-polypeptides with radially amphiphilic structure. They adopt a stable ?-helical conformation with a hydrophobic helical core and a charged exterior shell, formed by flexible hydrophobic side chains with terminal charge group. The radially amphiphilic polypeptides offer several advantages over conventional AMPs with regard to stability against protease and simplicity of design. They also exhibit high antibacterial activity against both Gram-negative and Gram-positive bacteria and low hemolytic activity. The AMPs thus provide a general platform for treating drug-resistant bacterial infections.

Abstract: The disclosure provides a class of pH-sensitive, helix/random conformation switchable antimicrobial polypeptide (HRS-AMP) compositions as a single agent to selectively kill bacteria (e.g., H. pylori) under acidic condition in the stomach with diminished bacterial resistance compared to currently used antibiotics. Methods of treating bacterial infections in the stomach are also provided.

Abstract: The invention provides antimicrobial polypeptides (AMPs) with high radial amphiphilicity. Unlike typical AMPs characterized by facial amphiphilicity or biomimetic antimicrobial polymers with randomly distributed charged and hydrophobic groups, these new AMPs are homo-polypeptides with radially amphiphilic structure. They adopt a stable ?-helical conformation with a hydrophobic helical core and a charged exterior shell, formed by flexible hydrophobic side chains with terminal charge group. The radially amphiphilic polypeptides offer several advantages over conventional AMPs with regard to stability against protease and simplicity of design. They also exhibit high antibacterial activity against both Gram-negative and Gram-positive bacteria and low hemolytic activity. The AMPs thus provide a general platform for treating drug-resistant bacterial infections.