Accessibility to Peptidoglycan Is Important for the Recognition of Gram-Positive Bacteria in Drosophila

Filipa Vaz, Ilias Kounatidis, Gonçalo Covas, Richard M. Parton, Maria Harkiolaki, Ilan Davis, Sergio Raposo Filipe, Petros Ligoxygakis

Research output: Contribution to journalArticlepeer-review

26 Citations (Scopus)
25 Downloads (Pure)


In Drosophila, it is thought that peptidoglycan recognition proteins (PGRPs) SA and LC structurally discriminate between bacterial peptidoglycans with lysine (Lys) or diaminopimelic (DAP) acid, respectively, thus inducing differential antimicrobial transcription response. Here, we find that accessibility to PG at the cell wall plays a central role in immunity to infection. When wall teichoic acids (WTAs) are genetically removed from S. aureus (Lys type) and Bacillus subtilis (DAP type), thus increasing accessibility, the binding of both PGRPs to either bacterium is increased. PGRP-SA and -LC double mutant flies are more susceptible to infection with both WTA-less bacteria. In addition, WTA-less bacteria grow better in PGRP-SA/-LC double mutant flies. Finally, infection with WTA-less bacteria abolishes any differential activation of downstream antimicrobial transcription. Our results indicate that accessibility to cell wall PG is a major factor in PGRP-mediated immunity and may be the cause for discrimination between classes of pathogens. It is widely believed that preference in recognition of structural features of bacterial peptidoglycan (PG) drives specificity in the Drosophila antibacterial response. Vaz et al. challenge this dogma by showing that accessibility to PG plays a central role in bacterial sensing and that structural discrimination is much less stringent than previously thought.

Original languageEnglish
Pages (from-to)2480-2492.e6
JournalCell Reports
Issue number8
Publication statusPublished - 21 May 2019


  • B. subtilis
  • Drosophila
  • innate immunity
  • peptidoglycan
  • PGRPs
  • S. aureus
  • TagO


Dive into the research topics of 'Accessibility to Peptidoglycan Is Important for the Recognition of Gram-Positive Bacteria in Drosophila'. Together they form a unique fingerprint.

Cite this