Antimicrobial Peptide Mimicking Primary Amine and Guanidine Containing Methacrylamide Copolymers Prepared by Raft...

Area of Science:

• Polymer Chemistry
• Biomaterials Science
• Antimicrobial Research

Background:

• Naturally occurring antimicrobial peptides (AMPs) are effective against diverse bacteria with low host toxicity.
• Synthetic polymers mimicking AMPs show promise, but activity depends on specific amino acid mimicry.
• Developing single polymers with combined lysine and arginine mimicry is a key challenge.

Purpose of the Study:

• To synthesize water-soluble copolymers incorporating lysine (aminopropyl methacrylamide, APMA) and arginine (guanadinopropyl methacrylamide, GPMA) mimics.
• To evaluate the antimicrobial efficacy of these copolymers against Gram-negative and Gram-positive bacteria.
• To assess the cytotoxicity of the synthesized copolymers toward mammalian cells.

Main Methods:

• Aqueous RAFT polymerization was used to create APMA/GPMA copolymers with controlled molecular weights (35-40) and narrow distributions.
• Antimicrobial activity was tested against various bacteria under different salt concentrations.
• Mammalian cell toxicity was evaluated using red blood cell hemolysis and MCF-7 cell MTT assays.

Main Results:

• APMA homopolymers and copolymers with low GPMA content exhibited significant antimicrobial activity against all tested bacteria.
• The synthesized copolymers demonstrated low toxicity to mammalian cells, as indicated by hemolysis and MTT assays.
• Antimicrobial efficacy was observed across a range of salt concentrations.

Conclusions:

• Copolymers containing APMA and GPMA effectively mimic natural AMPs, offering broad-spectrum antibacterial action.
• These synthetic AMP mimics present a viable strategy for developing new antimicrobial agents with reduced host toxicity.
• The balance of APMA and GPMA in the copolymer influences antimicrobial activity and safety profile.