An engineered protein-based submicromolar competitive inhibitor of the Staphylococcus aureus virulence factor aureolysin

Aureolysin, a secreted metallopeptidase (MP) from the thermolysin family, functions as a major virulence factor in Staphylococcus aureus. No specific aureolysin inhibitors have yet been described, making this an important target for the development of novel antimicrobial drugs in times of rampant an...

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Detalles Bibliográficos
Autores: Mendes, Soraia R., Eckhard, Ulrich, Rodríguez-Banqueri, Arturo, Guevara, Tibisay, Czermak, Peter, Marcos, Enrique, Vilcinskas, Andreas, Gomis-Rüth, F. Xavier
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2022
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/281121
Acceso en línea:http://hdl.handle.net/10261/281121
Access Level:acceso abierto
Palabra clave:Bacterial infection
Metallopeptidase
Protein inhibitor
Protein design
Therapeutic protein
Crystal structures
Descripción
Sumario:Aureolysin, a secreted metallopeptidase (MP) from the thermolysin family, functions as a major virulence factor in Staphylococcus aureus. No specific aureolysin inhibitors have yet been described, making this an important target for the development of novel antimicrobial drugs in times of rampant antibiotic resistance. Although small-molecule inhibitors are currently more common in the clinic, therapeutic proteins and peptides (TPs) are favourable due to their high selectivity, which reduces off-target toxicity and allows dosage tuning. The greater wax moth Galleria mellonella produces a unique defensive protein known as the insect metallopeptidase inhibitor (IMPI), which selectively inhibits some thermolysins from pathogenic bacteria. We determined the ability of IMPI to inhibit aureolysin in vitro and used crystal structures to ascertain its mechanism of action. This revealed that IMPI uses the “standard mechanism”, which has been poorly characterised for MPs in general. Accordingly, we designed a cohort of 12 single and multiple point mutants, the best of which (I57F) inhibited aureolysin with an estimated inhibition constant (Ki) of 346 nM. Given that animals lack thermolysins, our strategy may facilitate the development of safe TPs against staphylococcal infections, including strains resistant to conventional antibiotics.