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The antibacterial activity of peptide dendrimers and polymyxin B increases sharply above pH 7.4.

ABSTRACT: pH-activity profiling reveals that antimicrobial peptide dendrimers (AMPDs) kill Klebsiella pneumoniae and Methicillin-resistant Staphylococcus aureus (MRSA) at pH = 8.0, against which they are inactive at pH = 7.4, due to stronger electrostatic binding to bacterial cells at higher pH. A similar effect occurs with polymyxin B and might be general for polycationic antimicrobials.

SUBMITTER: Cai X

PROVIDER: S-EPMC8186529 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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The antibacterial activity of peptide dendrimers and polymyxin B increases sharply above pH 7.4.

Cai Xingguang X Javor Sacha S Gan Bee Ha BH Köhler Thilo T Reymond Jean-Louis JL

Chemical communications (Cambridge, England) 20210601 46

pH-activity profiling reveals that antimicrobial peptide dendrimers (AMPDs) kill Klebsiella pneumoniae and Methicillin-resistant Staphylococcus aureus (MRSA) at pH = 8.0, against which they are inactive at pH = 7.4, due to stronger electrostatic binding to bacterial cells at higher pH. A similar effect occurs with polymyxin B and might be general for polycationic antimicrobials. ...[more]

PMID: 33972964

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