Project description:In this study the isogenic Bacillus subtilis mutant strains ccpA topA+ and ccpA topA(S478P) were analyzed. The S478P suppressor mutation occurred when the ccpA mutant was grown on minimal medium supplemented with glucose and ammonium as single sources of carbon and nitrogen, respectively. Under these conditions, the ccpA mutant is unable to produce enough glutamate for growth, since gltAB, encoding the glutamate synthase, is not expressed. In order to get an insight how the S478P mutation in the DNA topoisomerase I affects expression on a global level, the two strains were subjected to a microarray analysis. Bacteria were cultivated in minimal medium supplemented with glucose and glutamate. The microarray data show that the topA(S478P) mutation results in a global re-direction of the central carbon metabolism that includes glutamate biosynthesis.
Project description:In this study two genome-reduced Bacillus subtilis strains lacking about 36% of dispensable genetic information were constructed using a markerless and scarless deletion method. In order to analyze the consequences of the deletions for the bacteria, a multi-omics characterization of the reference strain Δ6 (Westers et al., 2003; PMID 12949151) and the two deletion strains was carried out. Bacteria were cultivated in complex medium supplemented with glucose, and samples of the same cultures were subjected to metabolome, proteome, and transcriptome analyses.These revealed a massive re-organization of metabolism as well as substantial changes in the transcriptome and the proteome.
Project description:Bacillus subtilis ∆6 is a genome-reduced strain that was cured from six prophages and AT-rich islands. This strain is of great interest for biotechnological applications. Here, we announce the full-genome sequence of this strain. Interestingly, the conjugative element ICEBs1 has most likely undergone self-excision in B. subtilis ∆6.
Project description:Bacillus subtilis 3NA reaches high cell densities during fed-batch fermentation and is an interesting target for further optimization as a production strain. Here, we announce the full genome of B. subtilis 3NA. The presence of specific Bacillus subtilis 168 and W23 genetic features suggests that 3NA is a hybrid of these strains.
Project description:Sporulation by Bacillus subtilis is a cell density-dependent response to nutrient deprivation. Central to the decision of entering sporulation is a phosphorelay, through which sensor kinases promote phosphorylation of Spo0A. The phosphorelay integrates both positive and negative signals, ensuring that sporulation, a time- and energy-consuming process that may bring an ecological cost, is only triggered should other adaptations fail. Here we report that a gastrointestinal isolate of B. subtilis sporulates with high efficiency during growth, bypassing the cell density, nutritional, and other signals that normally make sporulation a post-exponential-phase response. Sporulation during growth occurs because Spo0A is more active per cell and in a higher fraction of the population than in a laboratory strain. This in turn, is primarily caused by the absence from the gut strain of the genes rapE and rapK, coding for two aspartyl phosphatases that negatively modulate the flow of phosphoryl groups to Spo0A. We show, in line with recent results, that activation of Spo0A through the phosphorelay is the limiting step for sporulation initiation in the gut strain. Our results further suggest that the phosphorelay is tuned to favor sporulation during growth in gastrointestinal B. subtilis isolates, presumably as a form of survival and/or propagation in the gut environment.
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:A thermophilic, heterotrophic and facultatively anaerobic bacterium designated strain D7XPN1 was isolated from Baku BakuKing™, a commercial food-waste degrading bioreactor (composter). The strain grew optimally at 45 °C (growth range between 24 and 50 °C) and pH 7 (growth pH range between pH 5 and 9) in Luria Broth supplemented with 0.3 % glucose. Strain D7XPN1 tolerated up to 7 % NaCl and showed amylolytic and xylanolytic activities. 16S rRNA gene analysis placed strain D7XPN1 in the cluster represented by Bacillus subtilis and the genome analysis of the 4.1 Mb genome sequence determined using RAST (Rapid Annotation using Subsystem Technology) indicated a total of 5116 genomic features were present of which 2320 features could be grouped into several subsystem categories. Of these, 615 features were related to carbohydrate metabolism which included a range of enzymes with potential in the biodegradation of food wastes, a property consistent with the ecological habitat of the isolate. ANIb (Average Nucleotide Identity based on BLAST) analysis with 49 Bacillus subtilis genomes indicated that it was distantly related to the three currently taxonomically validated B. subtilis subspecies namely B. subtilis subsp. subtilis (95.6 %), B. subtilis subsp. spizizenii (93 %) and B. subtilis subsp. inaquosorum (92 %) and based on our current knowledge warranted that it be included as a separate cluster together with strain JS which it was closely related (98.69 %). The close relationship of strains D7XPN1 and JS is also supported from our results from electronic DNA-DNA Hybridization (e-DDH) studies. Furthermore, our additional in-depth phylogenomic analyses using three different datasets unequivocally supported the creation of a fourth B. subtilis subspecies to include strains D7XPN1 and JS for which we propose strain D7XPN1T (=KCTC 33554T, JCM 30051T) as the type strain, and designate it as B. subtilis subsp. stecoris.