Project description:A collection of 61 Salmonella enterica serovar Typhimurium (S. Typhimurium) of animal and human origin, matched as closely as possible by phage type, antimicrobial resistance pattern and place / time of isolation, and sourced from farms or hospitals in Scotland, were analysed by antimicrobial susceptibility testing, phage typing, pulsed field gel electrophoresis (PFGE), plasmid profiling and DNA microarrays. PFGE of all 61 isolates revealed ten PFGE profiles, which clustered by phage type and antibiotic resistance pattern, with human and animal isolates distributed between PFGE profiles. Analysis of 23 representative S. Typhimurium strains hybridised to a composite Salmonella DNA microarray identified a small number of specific regions of genome variation between different phage types and PFGE profiles. These variable regions of DNA were typically located within prophage-like elements. Simple PCR assays were subsequently designed to discriminate between different isolates from the same geographical region.
Project description:We performed affinity purification coupled to quantitative mass spectrometry (AP-qMS) for proteins belonging to retrons of Salmonella enterica. We quantified the proteome of rcaT point mutants in Salmonella enterica. We quantified the proteome of phage P1vir in E. coli.
Project description:Peripheral blood transcriptome is an important intermediate data source for investigation of the mechanism of Salmonella invasion, proliferation, and transmission but its development in pig is quite limited. We challenged four-week-old piglets (Duroc × Landrace × Yorkshire crossbred) with Salmonella enterica serovar Typhimurium LT2 and investigated the peripheral blood miRNA expression profile before treatment (d0) and at 2 days post inoculation (dpi) using deep sequencing technology.
Project description:The early interaction of Salmonella enterica serovar typhimurium DT104 with intact small intestinal mucosa was studied in a Small Intestinal Segment Perfusion (SISP) model. Intestinal segments were infected with or without Salmonella. Scrapings from jejunal segments were collected after perfusion for 0, 2, 4, or 8 hours. Details of the SISP experiment are described in: Niewold TA, Veldhuizen EJ, van der Meulen J, Haagsman HP, de Wit AA, Smits MA, Tersteeg MH, Hulst MM. Using the Operon 13K pig oligonucleotide array differences in host gene expression were recorded between infected and uninfected segments within a single pig (isogenic comparisons), and between identical treated segments collected from 3 individual SISP pigs, all responding markedly different to infection with Salmonella (inter-animal comparisons). A Small Intestinal Segment Perfusion (SISP) test was performed with 3 pigs (pig no. 2, 3, and 4) (cross-bred YorkshireM-CM-^W(Large WhiteM-CM-^WLandrace)). Two adjacent segments prepared in the mid-jejunum of each pig were perfused for 1 hour with Salmonella enterica serovar typhimurium DT104 suspended in peptone solution (10E-09 CFU/ml) or with peptone solution alone (mock infected segment) respectively. Subsequently, segments were perfused with peptone solution alone for a maximum period of 8 hours. At 2, 4, and 8 hours a part of the infected segment was dissected to obtain mucosal scrappings. The same was done at 0 and 8 hours for the uninfected (mock) control segment. RNA isolated from scrappings was used for microarray comparisons using the Operon 13K pig oligonucleotide array. 9 comparisons were done. For each of the 3 SISP pigs, expression in the 8 hours perfused infected segment, perfused for 8 hours, was compared to expression in its adjacent mock infected segment (3 isogenic comparisons, 8 hpi.). Expression in the infected segment of each SISP pig, dissected after 2 or 4 hours of perfusion, was compared to expression in an infected segment dissected from another SISP pig (2 versus 3, 2 versus 4, and 3 versus 4 / 3 comparisons at 2 hpi., and 3 comparisons at 4 hpi.). Dye-swaps were performed for each comparison. jejunum pig, host-microbe interaction, Salmonella enterica serovar typhimurium DT104.
Project description:Salmonella enterica serovar Typhimurium is a gram-negative bacterium that can colonize the gut of humans and several species of food producing farm animals to cause enteric or septicaemic salmonellosis. Besides compromising public health and food safety, sub-clinical salmonellosis is also believed to be a major problem affecting the profitability of the pig industry. Distinct responses to Salmonella infection have been observed in pigs, some recovering faster and shedding lower levels of Salmonella in faeces than others (low shedders, LS versus persistent shedders, PS). This trait variation could indicate the existence of a genetic component to Salmonella shedding and resistance that may be exploited in animal breeding and disease diagnostics. The study aimed to characterize changes in miRNA expression in response to Salmonella infection.
Project description:Salmonella enterica serovar Typhimurium is a gram-negative bacterium that can colonize the gut of humans and several species of food producing farm animals to cause enteric or septicaemic salmonellosis. Besides compromising public health and food safety, sub-clinical salmonellosis is also believed to be a major problem affecting the profitability of the pig industry. Distinct responses to Salmonella infection have been observed in pigs, some recovering faster and shedding lower levels of Salmonella in faeces than others (low shedders, LS versus persistent shedders, PS). This trait variation could indicate the existence of a genetic component to Salmonella shedding and resistance that may be exploited in animal breeding and disease diagnostics. The study aimed to identify porcine genes and gene co-expression networks that differentiate distinct responses to Salmonella challenge with respect to faecal Salmonella shedding.
Project description:The early interaction of Salmonella enterica serovar typhimurium DT104 with intact small intestinal mucosa was studied in a Small Intestinal Segment Perfusion (SISP) model. Intestinal segments were infected with or without Salmonella. Scrapings from jejunal segments were collected after perfusion for 0, 2, 4, or 8 hours. Details of the SISP experiment are described in: Niewold TA, Veldhuizen EJ, van der Meulen J, Haagsman HP, de Wit AA, Smits MA, Tersteeg MH, Hulst MM. Using the Operon 13K pig oligonucleotide array differences in host gene expression were recorded between infected and uninfected segments within a single pig (isogenic comparisons), and between identical treated segments collected from 3 individual SISP pigs, all responding markedly different to infection with Salmonella (inter-animal comparisons).
Project description:Salmonella enterica serovar Typhimurium (S. Typhimurium) definitive phage type 104 (DT104) has caused significant morbidity and mortality in humans and animals for almost three decades. We have completed the full DNA sequence of one DT104 strain, NCTC13348 and show that the main differences between the genome of this isolate and the previously sequenced S. Typhimurium LT2 lie in integrated prophage elements and the Salmonella Genomic Island 1 encoding antibiotic resistance genes. Thirteen isolates of S. Typhimurium DT104 with different pulsed field gel electrophoresis (PFGE) profiles were analyzed by multi locus sequence typing (MLST), plasmid profiling, hybridization to a Pan-Salmonella DNA microarray and prophage-based multiplex PCR. All the isolates belonged to a single MLST type ST19. Microarray data demonstrated that the 13 DT104 isolates were remarkably conserved in gene content. The PFGE band-size differences in these isolates could be explained to a great extent by changes in prophage and plasmid content. Thus, here the nature of variation in different S. Typhimurium DT104 isolates is further defined at the genome level illustrating how this phage type is evolving over time.