Project description:RNA-seq experiment comparing the transcriptomes of Bacillus cereus G9241 WT to B. cereus G9241 ∆pBCXO1 when cultured both 37 and 25 degree celsius. B. cereus G9241 is a B. cereus sensu stricto strain that was isolated from a welder with and anthrax-like illness. B. cereus G9241 carries the plasmids pBCXO1 and pBC210. pBCX01 has 99.6% sequence identity to pXO1 carried by Bacillus anthracis and encodes the tripartite anthrax toxin genes and atxA, a mammalian virulence transcriptional regulator. B. cereus G9241 WT and B. cereus G9241 ∆pBCXO1 were cultured to exponential phase at either 37 or 25 degree celsius before samples were taken for RNA extraction, library prep and sequencing.
Project description:The goal of this study is the discovery of (a) meaningful phylogenomic relationships among members of this B. cereus/B. anthracis group, and (b) reliable gene-phenotype associations, e.g. recognition of links between genomic traits and the ability of certain strains to cause various forms of disease. We also tried to elucidate genome evolution aspects that may lead to the emergence of variants that are capable (or have the potential) of causing anthrax-like disease. This large-scale comparative genomics approach is unprecedented for this taxonomic group. Dr. A. Hoffmaster (CDC) provided the PFGRC with 73 B. cereus and B. anthracis isolates from the CDC culture collection. Of these, 27 were isolated from patients with severe or systemic disease; ten isolates of this group were obtained from patients (welding factory workers) with anthrax-like disease or from the environment near their workplace. Another set of 26 represented isolates from food-born illnesses. Of the 26 gastrointestinal disease isolates (GIDI), 10 were obtained from patients with diarrhea, whereas another set of 10 had been shown to harbor the emetic (vomit) toxin gene by PCR. The rest of the group consisted of 20 isolates with various phenotypes. All strains were screened for their genomic content using the B. cereus/B. anthracis species microarray.
Project description:Comparison of the Bacillus cereus with overexpressed Bacillus subtilis ComK (Bacillus cereus pNWcomKBsu) vs Bacillus cereus carrying empty plasmid (Bacillus cereus pNW33N) One condition design comparision of (IPTG induced overexpression construct vs IPTG induced empty plasmid) including a dye swap, 3 biological replicate
Project description:Comparison of the Bacillus cereus with induced ComK1 (pATK31 in sample 1-3) or ComK2 (pATK32 in sample 4-6) proteins vs Bacillus cereus carrying empty plasmid (pLM5 in all samples)
Project description:The advent of animal husbandry and hunting increased human exposure to zoonotic pathogens. To understand how a zoonotic disease influenced human evolution, we studied changes in human expression of anthrax toxin receptor 2 (ANTXR2), which encodes a cell surface protein necessary for Bacillus anthracis virulence toxins to cause anthrax disease. In immune cells, ANTXR2 was 8-fold down-regulated in all available human samples compared to non-human primates, indicating regulatory changes early in the evolution of modern humans. We also observed multiple genetic signatures consistent with recent positive selection driving a European-specific decrease in ANTXR2 expression in several non-immune tissues affected by anthrax toxins. Our observations fit a model in which humans adapted to anthrax disease following early ecological changes associated with hunting and scavenging, as well as a second period of adaptation after the rise of modern agriculture.
Project description:The goal of this study is the discovery of (a) meaningful phylogenomic relationships among members of this B. cereus/B. anthracis group, and (b) reliable gene-phenotype associations, e.g. recognition of links between genomic traits and the ability of certain strains to cause various forms of disease. We also tried to elucidate genome evolution aspects that may lead to the emergence of variants that are capable (or have the potential) of causing anthrax-like disease. This large-scale comparative genomics approach is unprecedented for this taxonomic group. Dr. A. Hoffmaster (CDC) provided the PFGRC with 73 B. cereus and B. anthracis isolates from the CDC culture collection. Of these, 27 were isolated from patients with severe or systemic disease; ten isolates of this group were obtained from patients (welding factory workers) with anthrax-like disease or from the environment near their workplace. Another set of 26 represented isolates from food-born illnesses. Of the 26 gastrointestinal disease isolates (GIDI), 10 were obtained from patients with diarrhea, whereas another set of 10 had been shown to harbor the emetic (vomit) toxin gene by PCR. The rest of the group consisted of 20 isolates with various phenotypes. All strains were screened for their genomic content using the B. cereus/B. anthracis species microarray. Seventy-three query strains were investigated in this study, with each query strain hybridized against the reference strain, Sterne. Dye-swap experiments were performed with all the 73 strains on both chipA and chipB of the microarray, for a total of four or more hybridizations per query strain. Each 70mer oligo spotted on the B. cereus species microarray is spotted once. Positive controls on the array consist of oligos designed from the sequenced reference genome, Sterne, and negative controls on the array consist of oligos designed from the thale cress plant, Arabidopsis thaliana.
Project description:The goal of this project was to screen soil samples for bacteria that may harbor B. anthracis virulence-associated genes (VAGs). There is currently no information about the prevalence of these types of organisms in the environment. Due to increased environmental monitoring of select agents by programs such as BioWatch and biodetection systems in place at the United States Post Offices and Department of State locations, it has become critical that we not only better understand the natural range of B. anthracis but also how widespread B. anthracis virulence genes are in environmental communities. Naturally occurring isolates containing the B. anthracis virulence genes could generate false-positive results in tests that detect the anthrax toxins, capsule or their associated genes. Understanding the true diversity and pathogenic potential of Bacillus spp. and particularly the B. cereus group is crucial not only in terms of understanding data from environmental monitoring but also diagnosing patients with clinical presentations similar to anthrax in the future. Severe and fatal disease caused by strains similar to B. anthracis could unnecessarily initiate emergency responses if anthrax was incorrectly suspected. Conversely, these strains may be used as bioterror agents requiring science-based responses; presently our limited understanding of these organisms does not permit data-driven decision making. We have investigated 700 aerobic sporoform soil isolates obtained from two areas in the Southwest of the US. Soil samples from the first site had been taken from public access land approximately 50 meters across from the work site of a fatal pneumonia case in a welding factory. This took place in year 2003 when B. cereus was isolated from a metal worker. The second site was targeted because of a recent case involving a deceased mule suspected to have died of a B. anthracis infection. Soil samples were initially analyzed at the CDC. Isolates were obtained by heating the soil at 65 degrees Celcius for 30 minutes followed by plating on agar media. All isolates were screened by PCR for the presence of B. anthracis genomic traits such as toxin genes (cya, lef and pag) as well as chromosomal markers. All isolates were also tested for their hemolytic activity as well as phage sensitivity.
Project description:Interventions: experimental group:Orally take Combined Bifidobacterium, Lactobacillus, Enterococcus and Bacillus cereus Tablets;control group:Orally take placebo
Study Design: Parallel