Light-mediated killing of pathogens by cationic photosensitisers is a promising antimicrobial approach that avoids the development of resistance inherent to the use of antimicrobials. In this study, we demonstrate that modification of different photosensitisers with the triphenylphosphonium cation yields derivatives with excellent photoantimicrobial activity against Gram-positive bacteria (ie, Staphylococcus aureus and Enterococcus faecalis). Thus, the triphenylphosphonium functional group should be considered for the development of photoantimicrobials for the selective killing of Gram-positive bacteria in the presence of Gram-negative species.

Inspired by natural transcription factors (TFs), researchers have explored the potential of artificial peptides for the recognition of specific DNA sequences, developing increasingly sophisticated systems that not only display excellent DNA binding properties, but also are endowed with new properties not found in their natural counterparts. Here we review some of the developments in the field of artificial peptide‐based DNA binders, focusing on the supramolecular and molecular design aspects of such systems.

The use of light‐activated triphenylphosphonium‐based antimicrobials to tackle the emerging problem of antimicrobial resistance has been proposed in this study. Chemical modification of phenalenone and perylene with triphenylphosphonium cations enhances their photoantimicrobial activity up to 107 times. Selective targeting of Gram‐positive bacteria is demonstrated. Further details can be found in the article by Roger Bresolí‐Obach, Ignacio Gispert and Diego García Peña et al. (https://doi.org/10.1002/e201800054). Cover art by M. Eugenio Vázquez, @ChemBioUSC