TY - JOUR TI - Bacterial autolysins trim cell surface peptidoglycan to prevent detection by the Drosophila innate immune system AU - Atilano, Magda Luciana AU - Pereira, Pedro Matos AU - Vaz, Filipa AU - Catalão, Maria João AU - Reed, Patricia AU - Grilo, Inês Ramos AU - Sobral, Rita Gonçalves AU - Ligoxygakis, Petros AU - Pinho, Mariana Gomes AU - Filipe, Sérgio Raposo A2 - Kolter, Roberto VL - 3 PY - 2014 DA - 2014/04/01 SP - e02277 C1 - eLife 2014;3:e02277 DO - 10.7554/eLife.02277 UR - https://doi.org/10.7554/eLife.02277 AB - Bacteria have to avoid recognition by the host immune system in order to establish a successful infection. Peptidoglycan, the principal constituent of virtually all bacterial surfaces, is a specific molecular signature recognized by dedicated host receptors, present in animals and plants, which trigger an immune response. Here we report that autolysins from Gram-positive pathogenic bacteria, enzymes capable of hydrolyzing peptidoglycan, have a major role in concealing this inflammatory molecule from Drosophila peptidoglycan recognition proteins (PGRPs). We show that autolysins trim the outermost peptidoglycan fragments and that in their absence bacterial virulence is impaired, as PGRPs can directly recognize leftover peptidoglycan extending beyond the external layers of bacterial proteins and polysaccharides. The activity of autolysins is not restricted to the producer cells but can also alter the surface of neighboring bacteria, facilitating the survival of the entire population in the infected host. KW - Staphylococcus aureus KW - Streptococcus pneumoniae KW - peptidoglycan KW - PGRP KW - peptidoglycan hydrolases KW - bacterial infection JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -