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Bacillus thuringiensis is an insect pathogen that is widely used as a biopesticide (3). Here we report the finished, annotated genome sequence of B. thuringiensis Al Hakam, which was collected in Iraq by the United Nations Special Commission (2).

The sequencing and analysis of two close relatives of Bacillus anthracis are reported. AFLP analysis of over 300 isolates of B. cereus, B. thuringiensis and B. anthracis identified two isolates as being very closely related to B. anthracis. One, a B. cereus, BcE33L, was isolated from a zebra carcass in Nambia; the second, a B. thuringiensis, 97-27, was isolated from a necrotic human wound. The B. cereus appears to be the closest anthracis relative sequenced to date. A core genome of over 3,900 genes was compiled for the Bacillus cereus group, including B anthracis. Comparative analysis of these two genomes with other members of the B. cereus group provides insight into the evolutionary relationships among these organisms. Evidence is presented that differential regulation modulates virulence, rather than simple acquisition of virulence factors. These genome sequences provide insight into the molecular mechanisms contributing to the host range and virulence of this group of organisms.

A small number of conserved canonical single nucleotide polymorphisms (canSNP) that define major phylogenetic branches for Bacillus anthracis were used to place a Sverdlovsk patient's B. anthracis genotype into 1 [...]

Bacillus anthracis, Bacillus cereus, and Bacillus thuringiensis are closely related gram-positive, spore-forming bacteria of the B. cereus sensu lato group. While independently derived strains of B. anthracis reveal conspicuous sequence homogeneity, environmental isolates of B. cereus and B. thuringiensis exhibit extensive genetic diversity. Here we report the sequencing and comparative analysis of the genomes of two members of the B. cereus group, B. thuringiensis 97-27 subsp, konkukian serotype H34, isolated from a necrotic human wound, and B. cereus E33L, which was isolated from a swab of a zebra carcass in Namibia. These two strains, when analyzed by amplified fragment length polymorphism within a collection of over 300 of B. cereus, B. thuringiensis, and B. anthracis isolates, appear closely related to B. anthracis. The B. cereus E33L isolate appears to be the nearest relative to B. anthracis identified thus far. Whole-genome sequencing of B. thuringiensis 97-27 and B. cereus E33L was undertaken to identify shared and unique genes among these isolates in comparison to the genomes of pathogenic strains B. anthracis Ames and B. cereus G9241 and nonpathogenic strains B. cereus ATCC 10987 and B. cereus ATCC 14579. Comparison of these genomes revealed differences in terms of virulence, metabolic competence, structural components, and regulatory mechanisms.

Bacillus thuringiensis, Bacillus cereus and Bacillus anthracis are three closely related species of the B.cereus group with each of them being economically important and their DNA isolates were analyzed using fluorescent amplified fragment length polymorphism (AFLP). Phytogenetic analysis of AFLP data showed diversity with B.thuringinesis and B.cereus compared to the monomorphic nature of B.anthracis.

Researchers used fluorescent amplified fragment length polymorphism to analyze 154 Bacillus cereus and Bacillus thuringiensis isolates taken from five different locations and compare them to reference strains. This method can be automated, allowing scientists to process very large samples.

The variation in the anthrax toxin in Bacillus anthracis was investigated by sequencing the 2,294-nucleotide protective antigen gene from 26 of the most diverse B. anthracis strains. Five different alleles were found among the strains, including two not seen in the 26-sample survey. One of the two alleles is a new missense mutation that is located adjacent to the highly antigenic region. Results also suggested that plasmid evolution of B. anthracis took place with few or no horizontal transfer between different strains.

The construction of a small-scale, non-selective procedure for DNA sample preparation supporting rapid-in-the-field polymerase chain reaction analysis for detection of microbial spores and cells is described. Three methods capable of releasing genomic DNA from three microorganisms were chosen for cell and spore disruption techniques. The reagents and buffers used in the three methods were changed and the techniques are miniaturized to provide maximum DNA yields.

A bacterial biosensor for benzene, toluene and similar compounds appears to be capable of accurately measuring environmental contaminants, making it a potentially inexpensive tool for field-ready assays. A reporter plasmid was constructed by placing the luc gene for firefyl luciferase directly under the control of the P(sub u) promoter and the xylR transcriptional activator of Pseudomonas putida mt-2. The biosensor cells were shown to detect benzene, toluene and xylene contamination in soil and water samples with high sensitivity and quantitative accuracy.

PCR analysis of 198 Bacillus anthracis isolates indicated a variable region of DNA sequence differing in length among the isolates. Five polymorphisms were characterized by the presence of two to six copies of the 12-bp tandem repeat 5'-CAATATCAACAA-3'. This variable-number tandem repeat region is found within a larger sequence containing one complete open reading frame that encodes a putative 30-kDa protein. Length variation did not alter the reading frame of the encoded protein and only modified the copy number of a 4-amino-acid sequence (QYQQ) from 2 to 6.

Carboxylate groups are essential in metal ion adsorption to Datura innoxia. This was indicated by findings that the esterification of carboxylate functionalities found in the cell walls of Datura innoxia leads to a decrease of as much as 40% in metal uptake, depending on the metal studied. A slight increase in metal ion uptake for Cu2 and Sr2 and a decline in uptake for Cd2 resulted from base hydrolysis of the biomaterial. These are due to the hydrolysis of esters native to the plant material.

Eu(super 3+) luminescence spectroscopy was employed in a study of the binding interactions between metal ions and bits of Datura innoxia cell walls. The results showed complete metal ion binding occured when the pH is greater than or equal to five. The affinity order was Cu(super 2+) and Ag(super +) > Ni(super 2+) > Cd(super 2+) > Eu(super 3+) > Sr(super 2+) > Ba(super 2+).

Eu3+ luminescence was used to understand the effect of immobilization in a polysilicate matrix on the binding of Eu3+ to the cell walls of Datura innoxia. The plant cell walls of D. innoxia is a potential metal binding agent for wastewater treatment processes. The results showed that immobilization in a polysilicate matrix enhances the binding of Eu3+ to D. innoxia cell material, possibly by causing new binding sites for Eu3+ to be accessible.

Abstract Background Castor bean (Ricinus communis) is an agricultural crop and garden ornamental that is widely cultivated and has been introduced worldwide. Understanding population structure and the distribution of castor bean cultivars has been challenging because of limited genetic variability. We analyzed the population genetics of R. communis in a worldwide collection of plants from germplasm and from naturalized populations in Florida, U.S. To assess genetic diversity we conducted survey sequencing of the genomes of seven diverse cultivars and compared the data to a reference genome assembly of a widespread cultivar (Hale). We determined the population genetic structure of 676 samples using single nucleotide polymorphisms (SNPs) at 48 loci. Results Bayesian clustering indicated five main groups worldwide and a repeated pattern of mixed genotypes in most countries. High levels of population differentiation occurred between most populations but this structure was not geographically based. Most molecular variance occurred within populations (74%) followed by 22% among populations, and 4% among continents. Samples from naturalized populations in Florida indicated significant population structuring consistent with local demes. There was significant population differentiation for 56 of 78 comparisons in Florida (pairwise population ϕPT values, p < 0.01). Conclusion Low levels of genetic diversity and mixing of genotypes have led to minimal geographic structuring of castor bean populations worldwide. Relatively few lineages occur and these are widely distributed. Our approach of determining population genetic structure using SNPs from genome-wide comparisons constitutes a framework for high-throughput analyses of genetic diversity in plants, particularly in species with limited genetic diversity.