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:Nanosynbacter lyticus type strain TM7x was the first cultivated member of the broadly prevelent, but poorly udnerstood Candidate Phylum Radiation super-phylum. TM7x was shown to be an obligate epibiont with a host range including Schaalia odontolyticus strain XH001. The process of infecting a naive host goes through multiple phases, from an initial binding and interaction phase we call the initial encounter, to a rapid die off of infected host cells, killing phase, followed by regrowth of the host cells, regrowth phase, and finally a stable symbiosis between the species, stable symbiosis.To obtain a better understanding of the process by which these species establish a stable symbiosis, we measured the transcriptome using RNA sequencing across the course of infection. We sampled infected host, XH001/TM7x, during the initial interaction, regrowth, and after attaining stable symbiosis, as well as naive host controls grown under the same culture conditions.