AUTHOR=Zhang Di , Chen Jingyi , Jing Qian , Chen Zheng , Ullah Azeem , Jiang Longguang , Zheng Ke , Yuan Cai , Huang Mingdong 

TITLE=Development of a Potent Antimicrobial Peptide With Photodynamic Activity

JOURNAL=Frontiers in Microbiology

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2021.624465

DOI=10.3389/fmicb.2021.624465

ISSN=1664-302X

ABSTRACT=<p>The emergence of antibiotic-resistant bacteria poses a serious challenge to medical practice worldwide. A small peptide with sequence RWRWRW was previously identified as a core antimicrobial peptide with limited antimicrobial spectrum to bacteria, especially Gram-positive bacteria. By conjugating this peptide and its analogs with lipophilic phthalocyanine (Pc), we identified a new antibiotic peptide [PcG<sub>3</sub>K<sub>5</sub>(RW)<sub>3</sub>]. The peptide demonstrates increased antimicrobial effect to both Gram-positive <italic>Staphylococcus aureus</italic> and Gram-negative <italic>Escherichia coli</italic>. In addition, Pc also provides added and potent antimicrobial effect upon red light illumination. The inhibitory efficacy of PcG<sub>3</sub>K<sub>5</sub>(RW)<sub>3</sub> was increased by ~140-fold to nanomolar range upon illumination. Moreover, PcG<sub>3</sub>K<sub>5</sub>(RW)<sub>3</sub> was safe for mammalian cell and promoted wound healing in the mouse infection model. Our work provides a new direction to optimize antimicrobial peptides to enhance antimicrobial efficacy.</p>