Project description:A specific interaction between the mold Scopulariopsis and S. equorum shifts the composition of the Staphylococcus community from dominance by a strong competitor, S. xylosus, to dominance by a weak competitor, S. equorum. To better understand specific genes and pathways involved with Scopulariopsis stimulation of S. equorum, we used RNA-seq to identify CDS that were up- and down-regulated in the genome of S. equorum in the presence and absence of the mold Scopulariopsis. We compared the effect of Scopulariopsis on the S. equorum transcriptome to the effect of Penicillium on the S. equorum transcriptome to determine why Scopulariopsis had such strong growth promotion effects relative to Penicillium. In the presence of both molds, Methionine biosynthesis and uptake pathways are strongly down-regulated, while Thiamine biosynthesis is up-regulated, suggesting that bacterial-fungal interactions alter the availability of free amino acids and nutrients in cheese environment for both partners. In the presence of Scopulariopsis only, there is a decrease in expression of genes involved with iron acquisition and the production of siderophores, notably the staphyloferrin B operon.
Project description:RNA-seq was used in combination with various analytical chemistry approaches to identify the chemical and genetic basis of pigment production of the bacterium Glutamicibacter arilaitensis when growing on cheese. This bacterium commonly found in cheese rinds where it co-occurs with Penicillium species and other molds. Pinkish-red pigments are produced by the bacterium in response to growth with Penicillium. Both chemical analyses and RNA-seq point to coproporphyrin III as the major metabolite leading to pigment formation.
Project description:Effect of the presence of Lactococcus lactis on Staphylococcus aureus transcriptome in cheese matrix. S. aureus was co-cultured with L. lactis LD61 in cheese matrix during 7 days. RNA samples were extracted at different time points (6 h, 8 h, 10 h, 24 h and 7 days) in order to monitor the dynamic response of S. aureus MW2 in cheese matrix in presence of L. lactis
Project description:Imaging run on co-culture and isolated cultures of Penicillium sp. #12 with Glutamicibacter arilaitensis. Both strains were isolated from cheese rinds and normalized to OD 0.1 before plating on 2.5% Cheese Curd agar and grown for 7 days at room temperature.
Project description:Imaging run on co-culture and isolated cultures of Penicillium sp. #12 with Glutamicibacter arilaitensis. Both strains were isolated from cheese rinds and normalized to OD 0.1 before plating on 2.5% Cheese Curd agar that was normalized to a pH of 5 and grown for 7 days at room temperature.
