Tunable glycine chemistry singles out Staphylococcus aureus in laboratory and mouse models

Summary. Researchers at the Indian Institute of Science Education and Research (IISER) Bhopal and collaborating institutes reported in Nature Communications on 5 October an electronically tunable chemical method that selectively modifies N-terminal glycine, a low-frequency molecular signature in peptides and proteins. The team first established the reaction on peptides and proteins and reports that its reactivity, selectivity and conjugate stability were unaffected by a range of biological additives. Because Staphylococcus aureus carries a pentaglycine-based signature in its peptidoglycan cell wall, the method allowed species-specific detection of S. aureus and its resistant strains, and it labelled the bacterium in fruit flies (Drosophila melanogaster) and in skin, tissue and blood infection models in mice.

Research context (RUO). The authors also report that the N-terminal glycine modification inhibited drug-susceptible and drug-resistant clinical strains of S. aureus in laboratory tests, including biofilm formation and preformed biofilms, and they describe an evaluation in a mouse wound model. These are preclinical findings from bacterial cultures, flies and mice, not from people. For laboratories the main interest is the chemistry: a residue-specific bioconjugation that can install several bioorthogonal handles late in a sequence and can be chemically reversed, which could be useful for peptide and protein labelling more broadly. The paper discloses a filed patent application and a company link for one author, so independent replication will be the next test.