Complete Genome Sequence of Listeria monocytogenes LL195, a Serotype 4b Strain from the 1983–1987 Listeriosis Epidemic in Switzerland

Abstract

The complete genome sequence of Listeria monocytogenes LL195, a serotype 4b clinical strain isolated during the 1983–1987 listeriosis epidemic in Switzerland, is presented.

Coordination of transcriptional and translational regulations in human epithelial cells infected by Listeria monocytogenes

“…Using RcisTarget, we analysed the enrichment for transcription factor binding sites in the promoter regions of the genes that were significantly transcriptionally induced at 2 h p.i. Unsurprisingly, binding sites for NF-κB subunits NFKB1/NFKB2/RELA dominated, with normalized enrichment scores 15 (NES) above 9 confirming that the early induction of NF-κB-dependent signalling during Lm infection of epithelial cells drives the inflammatory response. The effects of this early transcriptional activation (followed by a rapid downregulation) on the RNA and RFP profiles of a subset of cytokine genes is illustrated in 1C-D).…”

“…To clarify whether specific host transcripts were the object of translational regulation during infection, 15 we assessed mRNA expression and translation using high throughput Illumina mRNA sequencing (hereafter, RNA-seq) and ribosome profiling (hereafter, Ribo-seq) from biological samples in triplicates that were either non-infected, or recovered at 2, 5 or 10 h p.i. As expected from this technique, RNA-seq generally had a higher amount of uniquely mapped reads (24 to 32 million) than the Ribo-seq ( Figure 2-figure supplement 1A).…”

“…Between 5 and 10 h p.i., 4,537 genes were further deregulated, among which 1,078 genes (24% were similarly regulated in both RNA and RFP datasets ( Figure 2C). All types of differential regulations (positive 15 or negative, affecting the transcriptome or the translatome) were identified, arguing that over time various regulatory mechanisms cooperate to best adapt the expression of each host gene to changing conditions. Note that, due to the loss of one of the translatome samples at the 10 h time points, the proportion of transcripts that qualified as significantly regulated for RFPs in this dataset is likely underestimated.…”

“…In line with this, the translatome of Lpinfected murine macrophages has pioneered the attempts to discriminate between transcriptional and translational inputs in the fine-tuning of the inducible immune response to infection (Barry, Ingolia, & Vance, 2017). Barry et al highlighted that the superinduction of cytokine mRNA transcription allows infected cells to overcome the general translation elongation blockade imposed by Lp effectors, and thus launch a pro- 15 inflammatory response.…”

Geographical and longitudinal analysis of Listeria monocytogenes genetic diversity reveals its correlation with virulence and unique evolution

“…This ubiquitous bacterium is widespread in the environment (Gudmundsdottir et al 2004), and strongly adaptable to cold, acid, alkaline and osmotic stress (Raengpradub et al 2008;Sue et al 2004;Severino et al 2007). As a facultative intracellular parasitic bacterium, L. monocytogenes has a relatively broad host spectrum outbreak associated with soft cheese (Nelson et al 2004), LL195 was involved in the 1983-1987 Switzerland outbreak associated with vacherin (Weinmaier et al 2013), and Scott A was involved in the 1983 U.S. outbreak associated with pasteurized milk (Briers et al 2011). CLip80459 caused 85 deaths among 279 infected people associated with jellied pork tongue in France from 1999 to 2000(de Valk et al 2001.…”