Project description:We used a shotgun proteomics approach to compare protein expression of antimicrobial resistant strains of Yersinia pestis and Francisella tularensis with paired antimicrobial sensitive strains. Biomass from both log phase and stationary phase growth were analyzed.
Project description:A microarray was developed to screen rodent samples for pathogens of zoonotic importance In the work described here, a homologue to Yersinia pestis was found in rodent samples after screening with the microarray
Project description:Yersinia pestis, a Gram-negative bacterium is the causative agent of the fatal communicable disease plague. The disease had a profound impact on human history. Plague bacteria are usually transmitted to humans through the bite of an infected rat flea. Earlier studies have indicated that Y. pestis can survive in environmental matrices e.g. water and soil. This study aimed to generate a peptide-based screen for identification of Y. pestis particularly from environmental matrices. We employed a shotgun proteomic approach using nano-liquid chromatography-tandem mass spectrometry (nLC-MS/MS) to discover Y. pestis-specific peptides. Firstly, pure cultures of Y. pestis, Y. pseudotuberculosis, and Y. enterocolitica were grown, and their total cellular proteins were analyzed via MS, followed by in silico analysis of the obtained data. Secondly, Y. pestis-specific plasmids were analyzed using the Uniprot database, along with chromosomal-associated virulence proteins identified through extensive literature mining. To validate this screen, various concentrations of Y. pestis were spiked into the garden soil; and Y. pestis could be identified in all samples except un-spiked negative control soil sample. This study offers a valuable method for the identification of Y. pestis, by tandem mass spectrometry which may be used in environmental and clinical matrices.
Project description:A microarray was developed to screen rodent samples for pathogens of zoonotic importance In the work described here, a homologue to Yersinia pestis was found in rodent samples after screening with the microarray A number of rodent samples from the UK and Canada were identified as carrying a homologue to a Yersinia pestis gene
Project description:Temperature is a key environmental factor for facultative pathogens during the host adaptation response. To assess the functional role of temperature in Yersinia pestis, a microarray study was conducted comparing the Δpgm (pigmentation-negative) R88 strain grown at 37°C or 30°C.
Project description:The etiologic agent of bubonic plague, Yersinia pestis, senses cell density-dependent chemical signals to synchronize transcription between cells of the population in a process named quorum sensing. Though the closely related enteric pathogen Y. pseudotuberculosis uses quorum sensing system to regulate motility, the role of YpeIR quorum sensing in Y. pestis has been unclear. YpeIR is one of the AHL quorum sensing system in Y. pestis. In this study we performed transcriptional profiling experiments to identify Y. pestis YpeIR quorum sensing regulated functions at 37°C.
Project description:Yersinia pestis (Y. pestis) is the etiologic agent of the plague, an endemic zoonotic disease of critical clinical and historic importance. The species belongs to a genus comprising eleven members, three of which are human pathogens. Y. pestis and its closest extant relative, Yersinia pseudotuberculosis, are very similar in many respects, yet there is a distinct dichotomy between these species in terms of pathogenicity. Y. pseudotuberculosis produces a relatively benign food- or water-borne gastroenteritis with rare cases of potentially fatal bacteremia. In contrast, the characteristics of high infectivity and high mortality have made Y. pestis a pathogen of historic importance with devastating effects on the human populace over the course of three major pandemics. These qualities coupled with the emergence of multi-drug resistant variants make Y. pestis an ideal candidate for use as a bioterrorism agent. Consequentially, evolutionary biology of this organism has become a priority in the counter-terrorism research effort. The flow of genetic information within the Y. pseudotuberculosis/Y. pestis group motivated us to identify novel genes for the purpose of creating a pan-genome species DNA microarray to better understand the phylogenomic relationships among its members. Based on the sequence information be generated from the novel gene discovery project conducted at the PFGRC as well as other publicly available sources regarding Yersinia spp. genome sequences, we designed a species microarray which represents the hitherto known genetic repertoire of this taxonomic group. In order to create a species microarray that represents novel genes or genes with significant sequence variation, the ArrayOligoSelector software (http://arrayoligosel.sourceforge.net/) was used to design a 70-mer oligonucleotide for each of the annotated ORFs or partial ORFs. A detailed description of the 70-mer oligo design process and filters developed by the PFGRC can be found on the PFGRC web site at (http://pfgrc.tigr.org/presentations/seminars/oligo_design_final.pdf).