Project description:Listeria monocytogenes is an important food-borne pathogen which is frequently linked to ready-to-eat vegetables. In this work it was investigated by RNA-seq how the colonization of corn salad leaves and the commonly used packaging material polystyrene impacts on the transcriptome of L. monocytogenes NCTC 10887 at 4 °C and 22 °C. The strongest transcriptional differences occurred on corn salad at 4 °C versus polystyrene at 4 °C, yielding 2,629 differentially expressed genes (91.6% of protein-coding genes), indicating a habitat driven shift under cold-chain conditions. Corn salad promoted regulation of virulence related genes. The prfA gene was upregulated on corn salad compared to polystyrene at both temperatures (log2FC 2.43 at 22 °C and 4.16 at 4 °C), accompanied by increased hly (2.70), inlA (4.46), and inlB (2.10) expression at 4 °C. Stress/proteostasis gene expression was elevated on corn salad, including higher transcripts of clpP (3.34–3.51), clpE (5.58–6.89), and clpB (2.08–3.74), consistent with a stressed yet persistence-prone state on leaf surfaces. This indicates that L. monocytogenes persisting on leafy greens can remain transcriptionally primed for host interaction at 4 °C, implying that refrigeration alone may not mitigate risk on ready-to-eat produce, underlining the importance of pre-harvest hygiene.
Project description:RNA was extracted from the meninges of mice from either Specific pathogen free or Germ free facilities or from the offspring of mice reconstituted with different human microbiomes.
Project description:Microbial communities in the rhizosphere make significant contributions to crop health and nutrient cycling. However, their ability to perform important biogeochemical processes remains uncharacterized. Important functional genes, which characterize the rhizosphere microbial community, were identified to understand metabolic capabilities in the maize rhizosphere using GeoChip 3.0-based functional gene array method.