共查询到20条相似文献,搜索用时 15 毫秒
1.
Background
Complete sequencing and annotation of the 96.2 kb Bacillus anthracis plasmid, pXO2, predicted 85 open reading frames (ORFs). Bacillus cereus and Bacillus thuringiensis isolates that ranged in genomic similarity to B. anthracis, as determined by amplified fragment length polymorphism (AFLP) analysis, were examined by PCR for the presence of sequences similar to 47 pXO2 ORFs. 相似文献2.
Dwyer KG Lamonica JM Schumacher JA Williams LE Bishara J Lewandowski A Redkar R Patra G DelVecchio VG 《BMC genomics》2004,5(1):15-11
Background
Bacillus anthracis, Bacillus thuringiensis and Bacillus cereus are closely related members of the B. cereus-group of bacilli. Suppressive subtractive hybridization (SSH) was used to identify specific chromosomal sequences unique to B. anthracis. 相似文献3.
Background
Two putative methionine aminopeptidase genes,map(essential) andyflG(non-essential), were identified in the genome sequence ofBacillus subtilis. We investigated whether they can function as methionine aminopeptidases and further explored possible reasons for their essentiality or dispensability inB. subtilis. 相似文献4.
Shanmuga Sozhamannan Michael D Chute Farrell D McAfee Derrick E Fouts Arya Akmal Darrell R Galloway Alfred Mateczun Leslie W Baillie Timothy D Read 《BMC microbiology》2006,6(1):34-11
Background
Bacillus anthracis is considered to be a recently emerged clone within the Bacillus cereus sensu lato group. The B. anthracis genome sequence contains four putative lambdoid prophages. We undertook this study in order to understand whether the four prophages are unique to B. anthracis and whether they produce active phages. 相似文献5.
Background
The agriculturally important pasture grass tall fescue (Festuca arundinacea Schreb. syn. Lolium arundinaceum (Schreb.) Darbysh.) is an outbreeding allohexaploid, that may be more accurately described as a species complex consisting of three major (Continental, Mediterranean and rhizomatous) morphotypes. Observation of hybrid infertility in some crossing combinations between morphotypes suggests the possibility of independent origins from different diploid progenitors. This study aims to clarify the evolutionary relationships between each tall fescue morphotype through phylogenetic analysis using two low-copy nuclear genes (encoding plastid acetyl-CoA carboxylase [Acc1] and centroradialis [CEN]), the nuclear ribosomal DNA internal transcribed spacer (rDNA ITS) and the chloroplast DNA (cpDNA) genome-located matK gene. Other taxa within the closely related Lolium-Festuca species complex were also included in the study, to increase understanding of evolutionary processes in a taxonomic group characterised by multiple inter-specific hybridisation events. 相似文献6.
Agnieszka?Sekowska Valérie?Dénervaud Hiroki?Ashida Karine?Michoud Dieter?Haas Akiho?Yokota Antoine?Danchin
Background
The thiomethyl group of S-adenosylmethionine is often recycled as methionine from methylthioadenosine. The corresponding pathway has been unravelled in Bacillus subtilis. However methylthioadenosine is subjected to alternative degradative pathways depending on the organism. 相似文献7.
Background
Bacillus anthracis and Bacillus cereus can usually be distinguished by standard microbiological methods (e.g., motility, hemolysis, penicillin susceptibility and susceptibility to gamma phage) and PCR. However, we have identified 23 Bacillus spp. isolates that gave discrepant results when assayed by standard microbiological methods and PCR. We used multiple-locus variable-number tandem repeat analysis (MLVA), multiple-locus sequence typing (MLST), and phenotypic analysis to characterize these isolates, determine if they cluster phylogenetically and establish whether standard microbiological identification or PCR were associated with false positive/negative results. 相似文献8.
Background
Until now, the direct link between central carbon metabolism and DNA replication has been demonstrated only in Bacillus. subtilis. Therefore, we asked if this is a specific phenomenon, characteristic for this bacterium and perhaps for its close relatives, or a more general biological rule. 相似文献9.
Background
Some strains of Bacillus licheniformis have been improved by target-directed screening as well as by classical genetic manipulation and used in commercial thermostable α-amylase and alkaline protease production for over 40 years. Further improvements in production of these enzymes are desirable. 相似文献10.
Agnieszka Sekowska Laurence Mulard Susanne Krogh Jane KS Tse Antoine Danchin 《BMC microbiology》2001,1(1):15-10
Background
Methylthioadenosine, the main by-product of spermidine synthesis, is degraded inBacillus subtilisas adenine and methylthioribose. The latter is an excellent sulfur source and the precursor of quorum-sensing signalling molecules. Nothing was known about methylthioribose recycling in this organism. 相似文献11.
Background
Bacillus cereus and the closely related Bacillus thuringiensis are Gram positive opportunistic pathogens that may cause food poisoning, and the three secreted pore-forming cytotoxins Hbl, Nhe and CytK have been implicated as the causative agents of diarrhoeal disease. It has been proposed that the Hbl toxin is secreted using the flagellar export apparatus (FEA) despite the presence of Sec-type signal peptides. As protein secretion is of key importance in virulence of a microorganism, the mechanisms by which these toxins are secreted were further investigated. 相似文献12.
13.
T.L. Buhr A.A. Young Z.A. Minter C.M. Wells D.C. McPherson C.L. Hooban C.A. Johnson E.J. Prokop J.R. Crigler 《Journal of applied microbiology》2012,113(5):1037-1051
Aims
To develop test methods and evaluate the survival of Bacillus anthracis ?Sterne and Bacillus thuringiensis Al Hakam spores after exposure to hot, humid air.Methods and Results
Spores (>7 logs) of both strains were dried on six different test materials. Response surface methodology was employed to identify the limits of spore survival at optimal test combinations of temperature (60, 68, 77°C), relative humidity (60, 75, 90%) and time (1, 4, 7 days). No spores survived the harshest test run (77°C, 90% r.h., 7 days), while > 6·5 logs of spores survived the mildest test run (60°C, 60% r.h., 1 day). Spores of both strains inoculated on nylon webbing and polypropylene had greater survival rates at 68°C, 75% r.h., 4 days than spores on other materials. Electron microscopy showed no obvious physical damage to spores using hot, humid air, which contrasted with pH‐adjusted bleach decontamination.Conclusions
Test methods were developed to show that hot, humid air effectively inactivates B. anthracis ?Sterne and B. thuringiensis Al Hakam spores with similar kinetics.Significance and Impact of the Study
Hot, humid air is a potential alternative to conventional chemical decontamination. 相似文献14.
Background
Recombinant whole-cell sensors have already proven useful in the assessment of the bioavailability of environmental pollutants like heavy metals and organic compounds. In this work 19 recombinant bacterial strains representing various Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative (Escherichia coli, Pseudomonas fluorescens) bacteria were constructed to express the luminescence encoding genes luxCDABE (from Photorhabdus luminescens) as a response to bioavailable heavy metals ("lights-on" metal sensors containing metal-response elements, 13 strains) or in a constitutive manner ("lights-off" constructs, 6 strains). 相似文献15.
Background
Bacillus anthracis is an animal and human pathogen whose virulence is characterized by lethal and edema toxin, as well as a poly-glutamic acid capsule. In addition to these well characterized toxins, B. anthracis secretes several proteases and phospholipases, and a newly described toxin of the cholesterol-dependent cytolysin (CDC) family, Anthrolysin O (ALO). 相似文献16.
Background
Currently, there exists tens of different microbial and eukaryotic metabolic reconstructions (e.g., Escherichia coli, Saccharomyces cerevisiae, Bacillus subtilis) with many more under development. All of these reconstructions are inherently incomplete with some functionalities missing due to the lack of experimental and/or homology information. A key challenge in the automated generation of genome-scale reconstructions is the elucidation of these gaps and the subsequent generation of hypotheses to bridge them. 相似文献17.
C.S. Compaoré D.S. Nielsen H. Sawadogo‐Lingani T.S. Berner K.F. Nielsen D.B. Adimpong B. Diawara G.A. Ouédraogo M. Jakobsen L. Thorsen 《Journal of applied microbiology》2013,115(1):133-146
Aims
To identify and screen dominant Bacillus spp. strains isolated from Bikalga, fermented seeds of Hibiscus sabdariffa for their antimicrobial activities in brain heart infusion (BHI) medium and in a H. sabdariffa seed‐based medium. Further, to characterize the antimicrobial substances produced.Methods and Results
The strains were identified by gyrB gene sequencing and phenotypic tests as B. amyloliquefaciens ssp. plantarum. Their antimicrobial activity was determined by the agar spot and well assay, being inhibitory to a wide range of Gram‐positive and Gram‐negative pathogenic bacteria and fungi. Antimicrobial activity against Bacillus cereus was produced in H. sabdariffa seed‐based medium. PCR results revealed that the isolates have potential for the lipopeptides iturin, fengycin, surfactin, the polyketides difficidin, macrolactin, bacillaene and the dipeptide bacilysin production. Ultra‐high‐performance liquid chromatography‐time of flight mass spectrometry analysis of antimicrobial substance produced in BHI broth allowed identification of iturin, fengycin and surfactin.Conclusions
The Bacillus amyloliquefaciens ssp. plantarum exhibited broad‐spectrum antifungal and antibacterial properties. They produced several lipopeptide antibiotics and showed good potential for biological control of Bikalga.Significance and Impact of the Study
Pathogenic bacteria often occur in spontaneous food fermentations. This is the first report to identify indigenous B. amyloliquefaciens ssp. plantarum strains as potential protective starter cultures for safeguarding Bikalga. 相似文献18.
Background
Polyamine synthesis produces methylthioadenosine, which has to be disposed of. The cell recycles it into methionine through methylthioribose (MTR). Very little was known about MTR recycling for methionine salvage in Bacillus subtilis. 相似文献19.
Evaluation of DNA extraction methods for Bacillus anthracis spores isolated from spiked food samples
M.C. Thomas M.J. Shields K.R. Hahn T.W. Janzen N. Goji K.K. Amoako 《Journal of applied microbiology》2013,115(1):156-162
Aims
Nine commercial DNA extraction kits were evaluated for the isolation of DNA from 10‐fold serial dilutions of Bacillus anthracis spores using quantitative real‐time PCR (qPCR). The three kits determined by qPCR to yield the most sensitive and consistent detection (Epicenter MasterPure Gram Positive; MoBio PowerFood; ABI PrepSeq) were subsequently tested for their ability to isolate DNA from trace amounts of B. anthracis spores (approx. 6·5 × 101 and 1·3 × 102 CFU in 25 ml or 50 g of food sample) spiked into complex food samples including apple juice, ham, whole milk and bagged salad and recovered with immunomagnetic separation (IMS).Methods and Results
The MasterPure kit effectively and consistently isolated DNA from low amounts of B. anthracis spores captured from food samples. Detection was achieved from apple juice, ham, whole milk and bagged salad from as few as 65 ± 14, 68 ± 8, 66 ± 4 and 52 ± 16 CFU, respectively, and IMS samples were demonstrated to be free of PCR inhibitors.Conclusions
Detection of B. anthracis spores isolated from food by IMS differs substantially between commercial DNA extraction kits; however, sensitive results can be obtained with the MasterPure Gram Positive kit.Significance and Impact of the Study
The extraction protocol identified herein combined with IMS is novel for B. anthracis and allows detection of low levels of B. anthracis spores from contaminated food samples. 相似文献20.