Project description:AtxA, the master virulence regulator of Bacillus anthracis, regulates the expression of three toxins that are required for the pathogenicity of Bacillus anthracis. Recent transcriptome analyses also showed that AtxA affects a large number of genes on both chromosome and plasmid, suggesting its role as a global regulator. Its mechanism of gene regulation nor binding target in vivo was, however, not well understood. In this work, we conducted ChIP-seq for cataloging binding sites of AtxA in vivo and Cappable-seq for catalogging the transcription start sites on the B. anthracis genome. For detected regulons, single knockout strains were constructed and RNA-seq was conducted for each strain.
Project description:We have identified four repeats and ten domains that are novel in proteins encoded by the Bacillus anthracis str. Ames proteome using automated in silico methods. A "repeat" corresponds to a region comprising less than 55-amino-acid residues that occur more than once in the protein sequence and sometimes present in tandem. A "domain" corresponds to a conserved region with greater than 55-amino-acid residues and may be present as single or multiple copies in the protein sequence. These correspond to (1) 57-amino-acid-residue PxV domain, (2) 122-amino-acid-residue FxF domain, (3) 111-amino-acid-residue YEFF domain, (4) 109-amino-acid-residue IMxxH domain, (5) 103-amino-acid-residue VxxT domain, (6) 84-amino-acid-residue ExW domain, (7) 104-amino-acid-residue NTGFIG domain, (8) 36-amino-acid-residue NxGK repeat, (9) 95-amino-acid-residue VYV domain, (10) 75-amino-acid-residue KEWE domain, (11) 59-amino-acid-residue AFL domain, (12) 53-amino-acid-residue RIDVK repeat, (13) (a) 41-amino-acid-residue AGQF repeat and (b) 42-amino-acid-residue GSAL repeat. A repeat or domain type is characterized by specific conserved sequence motifs. We discuss the presence of these repeats and domains in proteins from other genomes and their probable secondary structure.
Project description:The aim of the study was to carry out a CGH study utilizing a set of 39 diverse Bacillus isolates. Thirty four B. cereus and five B. anthracis strains and isolates were chosen so as to represent different lineages based on previous characterizations, including MLEE and MLST (Helgason, Okstad et al. 2000; Helgason, Tourasse et al. 2004). They represent the spectrum of B. cereus phenotypic diversity by including soil, dairy and periodontal isolates in addition to virulent B. anthracis strains.
Project description:In this study we focused on understanding the effect of over expression of recombinant protective antigen (rPA) on the Bacillus anthracis metabolism and genes expression with the purpose of improving the production of this recombinant toxin in particular and recombinant proteins in general. To achieve this goal controlled growth of the B. anthracis ames strain transformed with pYS5 (PA producer) plasmid encoding protective antigen and the corresponding empty vector pSW4 (non-producer) were performed and protein production, bacterial growth characteristics and gene transcription pattern were analyzed. Controlled condition batch runs were performed for both strains and samples from early log (OD 3), log (OD 10) and late log (OD 16) phase were used for gene expression profiling. We found that most of the genes belonging to transport, TCA, glycolysis, PPP and amino acid biosynthesis were up-regulated in the lag phase samples which help the cell coping with the increased requirements of nutrient and energy for rPA expression. These pathways are down-regulated in the log and latelog phase as cellular stress response onsets, which is reflected in the decreased specific growth rate.
Project description:Pyrosequencing technology is a sequencing method that screens DNA nucleotide incorporation in real time. A set of coupled enzymatic reactions, together with bioluminescence, detects incorporated nucleotides in the form of light pulses, which produces a profile of characteristic peaks in a pyrogram. We used this technology to identify the warfare agent Bacillus anthracis by sequencing 4 single nucleotide polymorphisms (SNPs) in the rpoB gene as chromosomal markers for B. anthracis. In addition, 1 segment in each of the B. anthracis plasmids pXO1 and pXO2 was analyzed to determine the virulence status of the bacterial strains. Pyrosequencing technology is a powerful method to identify B. anthracis.
Project description:Identification of the specific WalR (YycF) binding regions on the B. subtilis chromosome during exponential and phosphate starvation growth phases. The data serves to extend the WalRK regulon in Bacillus subtilis and its role in cell wall metabolism, as well as implying a role in several other cellular processes.
Project description:Anthrax is a worldwide zoonotic disease caused by the spore-forming bacterium Bacillus anthracis. Primarily a disease of herbivores, human infections often result from direct contact with contaminated animal products (cutaneous and inhalational anthrax) or through consumption of infected meat (gastrointestinal anthrax). The genetic near neighbor, Bacillus cereus biovar anthracis (Bcbva), causes an anthrax-like illness in the wildlife and livestock of west and central Africa due to the presence and expression of B. anthracis-specific virulence factors in this background. While Bcbva infections have not been reported in humans, a recent seroprevalence study detected Bcbva antibodies in the rural population around Taï National Park. This work describes the development of new TaqMan multiplex PCRs for the simultaneous detection of B. anthracis and Bcbva. The assays are designed to amplify Ba-1, capB, and lef markers in B. anthracis and genomic island IV (GI4), capB, and lef in Bcbva. Our assays allow for the rapid discrimination of B. anthracis and Bcbva and will provide insights into the molecular epidemiology of these two important pathogens that share an overlapping geographical range in west and central Africa.