Project description:Reference and type strains of well-known bacteria have been a cornerstone of microbiology research for decades. The sharing of well-characterized isolates among laboratories has run in parallel with research efforts and enhanced the reproducibility of experiments, leading to a wealth of knowledge about trait variation in different species and the underlying genetics. Campylobacter jejuni strain NCTC 11168, deposited at the National Collection of Type Cultures in 1977, has been adopted widely as a reference strain by researchers worldwide and was the first Campylobacter for which the complete genome was published (in 2000). In this study, we collected 23 C. jejuni NCTC 11168 reference isolates from laboratories across the UK and compared variation in simple laboratory phenotypes with genetic variation in sequenced genomes. Putatively identical isolates, identified previously to have aberrant phenotypes, varied by up to 281 SNPs (in 15 genes) compared to the most recent reference strain. Isolates also display considerable phenotype variation in motility, morphology, growth at 37 °C, invasion of chicken and human cell lines, and susceptibility to ampicillin. This study provides evidence of ongoing evolutionary change among C. jejuni isolates as they are cultured in different laboratories and highlights the need for careful consideration of genetic variation within laboratory reference strains. This article contains data hosted by Microreact.
Project description:Gene content comparison of control C. jejuni subsp. jejuni strain 11168 which colonizes and causes disease in C57BL/6 IL-10-/- mice versus C. jejuni strains D6844, D6845, D6846, D6847, D6848, D6849, D0121, D0835, D2586, D2600,33560 and NW in the C57BL/6 IL-10-/- mice. Keywords: DNA/DNA comparison
Project description:Campylobacter jejuni NCTC 11168 is widely used in research, but at least two variants have been reported. The available genome was sequenced from a variant which later showed a different phenotype and gene expression profile. Here we present the complete genome sequence of a second variant of C. jejuni NCTC 11168.
Project description:Upon colonization in the host gastrointestinal tract, the enteric bacterial pathogen Campylobacter jejuni is exposed to a variety of signaling molecules including the catecholamine hormones epinephrine (Epi) and norepinephrine (NE). NE has been observed to stimulate the growth and potentially enhance the pathogenicity of C. jejuni. However, the underlying mechanisms are still largely unknown. In this study, both Epi and NE were also observed to promote C. jejuni growth in MEMα-based iron-restricted medium. Adhesion and invasion of Caco-2 cells by C. jejuni were also enhanced upon exposure to Epi or NE. To further examine the effect of Epi or NE on the pathobiology of C. jejuni, transcriptomic profiles were conducted for C. jejuni NCTC 11168 that was cultured in iron-restricted medium supplemented with Epi or NE. Compared to the genes expressed in the absence of the catecholamine hormones, 183 and 156 genes were differentially expressed in C. jejuni NCTC 11168 that was grown in the presence of Epi and NE, respectively. Of these differentially expressed genes, 102 genes were common for both Epi and NE treatments. The genes differentially expressed by Epi or NE are involved in diverse cellular functions including iron uptake, motility, virulence, oxidative stress response, nitrosative stress tolerance, enzyme metabolism, DNA repair and metabolism and ribosomal protein biosynthesis. The transcriptome analysis indicated that Epi and NE have similar effects on the gene expression of C. jejuni, and provided insights into the delicate interaction between C. jejuni and intestinal stress hormones in the host.
