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Stenotrophomonas maltophilia differential gene expression in synthetic cystic fibrosis sputum identifies shared and cystic fibrosis strain-specific expression responses to the sputum environment

ABSTRACT: We characterized the transcriptional responses of three S. maltophilia strains during exposure to synthetic CF sputum media (SCFM2) to gain insight into how this organism interacts with the host in the CF lung. These efforts led to the identification of 881 transcripts differentially expressed by all three strains, many of which reflect different metabolic pathways used by S. maltophilia in sputum, and altered stress responses. The latter correlated with increased resistance to peroxide exposure after pre-growth in SCFM2. We also compared the SCFM2 transcriptomes of two S. maltophilia CF isolates with the SCFM2 transcriptome of the acute infection model strain, S. maltophilia K279A, allowing us to identify CF isolate-specific signatures in differential gene expression that may be suggestive of adaptation to the CF lung. Each strain also possessed genes not shared by the other two and here we show that expression of some of the accessory genes in each strain are changed in response to SCFM2. Collectively, this work details the response of S. maltophilia to the CF lung environment, identifying potential survival strategies and metabolic pathways used by S. maltophilia during infections.

ORGANISM(S): Stenotrophomonas maltophilia

PROVIDER: GSE125704 | GEO | 2019/01/30

REPOSITORIES: GEO

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Stenotrophomonas maltophilia differential gene expression in synthetic cystic fibrosis sputum identifies shared and cystic fibrosis strain-specific expression responses to the sputum environment

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