# Precise Construction of an Antimicrobial Peptide Targeting Bacterial Cell Membranes Derived From Natural Peptides

## TL;DR

Scientists designed a powerful antimicrobial peptide that targets bacteria by modifying natural peptides, showing strong effects in fighting drug-resistant infections in lab and animal tests.

## Contribution

A novel antimicrobial peptide (P 3-3R-8I) was precisely engineered to target bacterial membranes and DNA, demonstrating efficacy against drug-resistant bacteria.

## Key findings

- P 3-3R-8I shows strong antibacterial activity against MRSA and E. coli by penetrating membranes and binding to DNA.
- The peptide effectively alleviates MRSA-infected wounds and systemic sepsis in rat models.
- The approach offers a strategy for overcoming antimicrobial resistance through precise AMP construction.

## Abstract

Antimicrobial peptides (AMPs) are promising alternatives to overcome antimicrobial resistance (AMR). However, precise construction of an AMP targeting bacterial cell membranes derived from natural peptides remains a great challenges. Although the artificial intelligence (AI) algorithm‐assisted screening method has achieved unprecedented successes, it's difficult to predict the targets of AMPs obtained from this method. To address this, an AMP (P 3‐3R‐8I) based on several natural peptides derived from insect cuticle was constructed precisely via amino acid mutation. The mutated amino acids Arginine (R) and Isoleucine (I) are expected to target the bacterial cell membranes. Surprisingly, P 3‐3R‐8I exhibits super antibacterial capability against two representative bacteria: methicillin‐resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli), which could be attributed to the ability to quickly penetrate bacterial cell membranes and then to bind to bacterial DNA of P 3‐3R‐8I, resulting in the suppression of DNA replication. In rats’ model, the MRSA‐infected wound could be alleviated by P 3‐3R‐8I obviously, as well as lung and spleen infections in MRSA‐induced systemic sepsis. Our findings provide a prospect for the precise construction of AMPs targeting bacterial cell membranes as well as a means of overcoming AMR, offering a strategy for drug‐resistant bacteria‐induced tissue repair.

An AMP (P 3‐3R‐8I) based on natural peptides, which can target bacterial cell membranes, was precisely constructed via amino acid mutation. P 3‐3R‐8I exhibits antibacterial capability which could be attributed to the ability of P 3‐3R‐8I to quickly penetrate bacterial cell membranes and then to bind to bacterial DNA. In vivo, the MRSA‐infected wound and systemic sepsis in rats could be repaired by P 3‐3R‐8I.