Editor: Rob Delahay
A yeast-based genetic screen for identification of pathogenic Salmonella proteins
Article first published online: 8 MAY 2009
© 2009 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved
FEMS Microbiology Letters
Volume 296, Issue 2, pages 167–177, July 2009
How to Cite
Alemán, A., Fernández-Piñar, P., Pérez-Núñez, D., Rotger, R., Martín, H. and Molina, M. (2009), A yeast-based genetic screen for identification of pathogenic Salmonella proteins. FEMS Microbiology Letters, 296: 167–177. doi: 10.1111/j.1574-6968.2009.01630.x
- Issue published online: 12 JUN 2009
- Article first published online: 8 MAY 2009
- Received 24 November 2008; accepted 15 April 2009.Final version published online 8 May 2009.
- TTSS effectors;
- pathogenic protein
Salmonella uses type III secretion systems (TTSS) to deliver pathogenic proteins into the host cells. These translocated effectors induce bacterial internalization and intracellular proliferation by targeting important cellular processes that are conserved among eukaryotes. Here, we assessed the feasibility of performing a genetic screen in yeast to identify novel Salmonella effectors, by searching for genes that produce toxicity when expressed in this model system. We identified several known TTSS-translocated effectors and found that two of them, SteC and SseF, from Salmonella enterica serovar Typhimurium, interfere with cytoskeletal dynamics as they do in mammalian cells. We also identified 11 genes of unknown function (seven from S. Typhi and four from S. Typhimurium) that display features commonly showed by effector proteins, such as a (G+C) content lower than the average for the chromosome, suggesting their acquisition by horizontal transfer processes. Five of these proteins are highly conserved only among Salmonella serovars, whereas the other six are also conserved in other pathogenic or opportunistic enterobacteria. Moreover, we identified other proteins that share specific activity domains with either translocated or bacterial-confined proteins known to be involved in pathogenesis, which might also act as virulence proteins.