Project description:Background: Pantoea ananatis LMG 2665T synthesizes and utilizes acyl homoserine lactones (AHLs) for signaling. In this strain, short chain AHLs (C4 to C8) are produced by the EanI/R quorum sensing (QS) system that is involved in pathogenicity and biofilm formation. The complete set of genes regulated by the EanI/R system in P. ananatis LMG 2665T is still not fully known. In the present study, RNA-seq was used to analyze the transcriptome profiles controlled by the EanI/R system in this strain by comparing the wild type strain and its QS mutant 2665T ean∆I/R during lag and log stages. The RNA seq data was validated by RT qPCR. Results: The results showed that the EanI/R regulon in P. ananatis LMG 2665T comprised 144 genes, constituting 3.3% of the whole transcriptome under the experimental conditions in this study. The majority of genes regulated by the EanI/R system included genes for flagella assembly, bacterial chemotaxis, pyruvate metabolism, two component system, metabolic pathways, microbial metabolism and biosynthesis of secondary metabolites. Conclusions: This is the first study to identify the EanI/R QS regulon in P. ananatis LMG 2665T. Functional analysis of genes regulated the EanI/R system in LMG 2665T could help unveil genes that play a vital role in pathogenesis and survival strategies of this pathogen.
Project description:S. anginosus, S. aureus LMG 10147 and P. aeruginosa DK2 are often co-isolated in sputum samples from cystic fibrosis patients. We found that S. anginosus LMG 14502 becomes less suceptible towards treatment with several antibiotics when it's grown together with S. aureus LMG 10147 and P. aeruginosa DK2, compared to when it's grown alone. In order to elucidate the molecular mechanisms responsible, we performed RNA-seq of an S. anginosus monospecies biofilm and of a multispecies bioiflm of S. anginosus, S. aureus and P. aeruginosa. First, biofilms of S. anginosus alone or in combination with S. aureus and P. aeruginosa were grown. Next, RNA was isolated. Subsequently, a Truseq stranded RNA library preparation kit (Illumina) was used to create strand specific libraries. After a quality and concentration control, the libraries were equimolarly pooled and sequenced using an Illumina NextSeq 500, generating 75bp unpaired reads.