nad a22 4500 555301192 20190206082733.0 cr unu---uuuuu 190206e20181201xx s 000 0 eng 10.1038/s41396-018-0231-9 doi (ZORA)oai:www.zora.uzh.ch:161755 580 ddc Low spatial structure and selection against secreted virulence factors attenuates pathogenicity in Pseudomonas aeruginosa [Elektronische Daten] [Elisa T Granato, Christoph Ziegenhain, Rasmus L Marvig, Rolf Kümmerli] closedAccess eu-repo Bacterial opportunistic pathogens are feared for their difficult-to-treat nosocomial infections and for causing morbidity in immunocompromised patients. Here, we study how such a versatile opportunist, Pseudomonas aeruginosa, adapts to conditions inside and outside its model host Caenorhabditis elegans, and use phenotypic and genotypic screens to identify the mechanistic basis of virulence evolution. We found that virulence significantly dropped in unstructured environments both in the presence and absence of the host, but remained unchanged in spatially structured environments. Reduction of virulence was either driven by a substantial decline in the production of siderophores (in treatments without hosts) or toxins and proteases (in treatments with hosts). Whole-genome sequencing of evolved clones revealed positive selection and parallel evolution across replicates, and showed an accumulation of mutations in regulator genes controlling virulence factor expression. Our study identifies the spatial structure of the non-host environment as a key driver of virulence evolution in an opportunistic pathogen. Department of Plant and Microbial Biology zora Ecology, Evolution, Behavior and Systematics, Microbiology zora Granato Elisa T. joint author Ziegenhain Christoph joint author Marvig Rasmus L. joint author Kümmerli Rolf joint author The ISME journal 12(12):2907-2918 https://www.zora.uzh.ch/161755 text/html WWW-Backlink auf das Repository 1 Journal Article PeerReviewed zora ZORA 856 40 https://www.zora.uzh.ch/161755 text/html WWW-Backlink auf das Repository ZORA 700 1- Granato Elisa T. joint author ZORA 700 1- Ziegenhain Christoph joint author ZORA 700 1- Marvig Rasmus L. joint author ZORA 700 1- Kümmerli Rolf joint author ZORA 773 0- The ISME journal 12(12):2907-2918 BK010053 XK010053 XK010000 ZORA ZORA ZORA Journal Article closedAccess