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Antibody-Drug Conjugates (ADCs) are growing in importance for the treatment of both solid and haematological malignancies. There is a demand for new payloads with novel mechanisms of action that may offer enhanced therapeutic efficacy, especially in patients who develop resistance. We report here a class of Cyclopropabenzindole-Pyridinobenzodiazepine (CBI-PDD) DNA cross-linking payloads that simultaneously alkylate guanine (G) and adenine (A) bases in the DNA minor groove with a defined sequence selectivity. The lead payload, FGX8-46 (6), produces sequence-selective G-A cross-links and affords cytotoxicity in the low picomolar region across a panel of 11 human tumour cell lines. When conjugated to the antibody cetuximab at an average Drug-Antibody Ratio (DAR) of 2, an ADC is produced with significant antitumour activity at 1 mg/kg in a target-relevant human tumour xenograft mouse model with an unexpectedly high tolerability (i.e., no weight loss observed at doses as high as 45 mg/kg i.v., single dose). A class of Cyclopropabenzindole-Pyridinobenzodiazepine (CBI-PDD) DNA cross-linking payloads, used in Antibody-Drug Conjugates, alkylate guanine and adenine bases in the DNA minor groove with a defined sequence selectivity. [ABSTRACT FROM AUTHOR]

The pyrrolo[2,1-c][1,4]benzodiazepines (PBDs) are a family of sequence-selective DNA minor-groove binding agents that form a covalent aminal bond between their C11-position and the C2-NH2 groups of guanine bases. The first example of a PBD monomer, the natural product anthramycin, was discovered in the 1960s, and the best known PBD dimer, SJG-136 (also known as SG2000, NSC 694501 or BN2629), was synthesized in the 1990s and has recently completed Phase II clinical trials in patients with leukaemia and ovarian cancer. More recently, PBD dimer analogues are being attached to tumor-targeting antibodies to create antibody-drug conjugates (ADCs), a number of which are now in clinical trials, with many others in pre-clinical development. This Review maps the development from anthramycin to the first PBD dimers, and then to PBD-containing ADCs, and explores both structure-activity relationships (SARs) and the biology of PBDs, and the strategies for their use as payloads for ADCs. [ABSTRACT FROM AUTHOR]

Die Pyrrolo[2,1 ‐ c][1,4]benzodiazepine (PBDs) sind eine Familie sequenzselektiver Wirkstoffe, die an die kleine Furche der DNA binden und eine kovalente Aminalbindung zwischen der C11 ‐ Position und den C2 ‐ NH2 ‐ Gruppen der Guaninbasen bilden. Anthramycin ist das erste Beispiel eines PBD ‐ Monomers und wurde in den 1960er Jahren entdeckt. In den 1990er Jahren wurde das bekannteste PBD ‐ Dimer SJG ‐ 136 entwickelt und hat jetzt bereits die klinischen Studien der Phase II in Patienten mit Leukämie und Eierstockkrebs durchlaufen. Seit kurzem werden aus PBD ‐ Dimeranaloga und spezifisch an Tumorzellen bindenden Antikörpern Antikörper ‐ Wirkstoff ‐ Konjugate (ADCs) hergestellt. Von diesen befinden sich derzeit mehrere in klinischen Studien und viele andere in der präklinischen Entwicklung. Dieser Aufsatz zeigt die Entwicklung der PBDs ausgehend von Anthramycin über die ersten PBD ‐ Dimere bis hin zu PBD ‐ haltigen ADCs und behandelt sowohl die Struktur ‐ Wirkungs ‐ Beziehungen und die Biologie der PBDs als auch die Strategien für ihre Verwendung als Wirkstoffkomponente in ADCs. PBDs in ADCs: Pyrrolobenzodiazepine (PBDs; Beispiel siehe Bild) sind DNA ‐ interaktive Tumortherapeutika, die sequenzselektiv an die Guaninbasen der kleinen Furche der DNA binden. Sie sind stark zytotoxisch und werden als Wirkstoffkomponente in Antikörper ‐ Wirkstoff ‐ Konjugaten (ADCs) verwendet. Dieser Aufsatz beschreibt ihre Entwicklung, ausgehend von der Entdeckung des Naturstoffs Anthramycin bis hin zur Verwendung von PBD ‐ Dimer ‐ Wirkstoffen in ADCs. [ABSTRACT FROM AUTHOR]

The pyrrolobenzodiazepine (PBD) and duocarmycin families are DNA-interactive agents that covalently bond to guanine (G) and adenine (A) bases, respectively, and that have been joined together to create synthetic dimers capable of cross-linking G-G, A-A, and G-A bases. Three G-A alkylating dimers have been reported in publications to date, with defined DNA-binding sites proposed for two of them. In this study we have used molecular dynamics simulations to elucidate preferred DNA-binding sites for the three published molecular types. For the PBD-CPI dimer UTA-6026 (1), our simulations correctly predicted its favoured binding site (i.e., 50-C(G)AATTA-30) as identified by DNA cleavage studies. However, for the PBD-CI molecule ('Compound 11', 3), we were unable to reconcile the results of our simulations with the reported preferred cross-linking sequence (50-ATTTTCC(G)-30). We found that the molecule is too short to span the five base pairs between the A and G bases as claimed, but should target instead a sequence such as 50-ATTTC(G)-30 with two less base pairs between the reacting G and A residues. Our simulation results for this hybrid dimer are also in accord with the very low interstrand cross-linking and in vitro cytotoxicity activities reported for it. Although a preferred cross-linking sequence was not reported for the third hybrid dimer ('27eS', 2), our simulations predict that it should span two base pairs between covalently reacting G and A bases (e.g., 50-GTAT(A)-30). [ABSTRACT FROM AUTHOR]

Pyrrolobenzodiazepines (PBDs) are covalent-binding DNA-interactive agents with growing importance as payloads in Antibody Drug Conjugates (ADCs). Until now, PBDs were thought to covalently bond to C2-NH2 groups of guanines in the DNA-minor groove across a three-base-pair recognition sequence. Using HPLC/MS methodology with designed hairpin and duplex oligonucleotides, we have now demonstrated that the PBD Dimer SJG-136 and the C8-conjugated PBD Monomer GWL-78 can covalently bond to a terminal guanine of DNA, with the PBD skeleton spanning only two base pairs. Control experiments with the non-C8-conjugated anthramycin along with molecular dynamics simulations suggest that the C8-substituent of a PBD Monomer, or one-half of a PBD Dimer, may provide stability for the adduct. This observation highlights the importance of PBD C8-substituents, and also suggests that PBDs may bind to terminal guanines within stretches of DNA in cells, thus representing a potentially novel mechanism of action at the end of DNA strand breaks. [ABSTRACT FROM AUTHOR]

DNA binding 4-(1-methyl-1H-pyrrol-3-yl)benzenamine(MPB) building blocks have been developed that span two DNA base pairswith a strong preference for GC-rich DNA. They have been conjugatedto a pyrrolo[2,1-c][1,4]benzodiazepine (PBD) moleculeto produce C8-linked PBD–MPB hybrids that can stabilize GC-richDNA by up to 13-fold compared to AT-rich DNA. Some have subpicomolarIC50values in human tumor cell lines and in primary chroniclymphocytic leukemia cells, while being up to 6 orders less cytotoxicin the non-tumor cell line WI38, suggesting that key DNA sequencesmay be relevant targets in these ultrasensitive cancer cell lines.One conjugate, 7h(KMR-28-39), which has femtomolar activityin the breast cancer cell line MDA-MB-231, has significant dose-dependentantitumor activity in MDA-MB-231 (breast) and MIA PaCa-2 (pancreatic)human tumor xenograft mouse models with insignificant toxicity attherapeutic doses. Preliminary studies suggest that 7hmay sterically inhibit interaction of the transcription factor NF-κBwith its cognate DNA binding sequence. [ABSTRACT FROM AUTHOR]

The article evaluates Idaho Technology Incorporated's (ITI) RAZOR® EX Anthrax Air Detection System for detecting Bacillus anthracis spores collected by air collection devices.

This article explores the links between the management of remote workers and dispersed teams and the use of information systems (IS). We aim to develop a framework to evaluate IS' potential to support remote control. To gain an understanding of the contribution IS could make, the article first focuses on a specific type of IS, namely workflow management systems (WfMSs). Case studies are used to demonstrate how such systems can support diverse control approaches independent of the location of employees and managers. The article then goes on to present a generic evaluation framework for the potential of IS to support remote control. The resulting increased understanding of the role of IS in remote control is also intended to enhance the success of distant working. [ABSTRACT FROM AUTHOR]

Analyzes 198 Bacillus anthracis isolates for the presence of a variable region of DNA sequence differing in length. Strains and sources; High degree of polymorphism in the variable-number tandem repeat region; Correlation between categories and geographic distribution.

Analysis the tissue samples of tan outbreak of human anthrax which occurred in Sverdlovsk, Union of Soviet Socialist Republic (now Ekaterinburgh Russia) in 1979. What contributed to this outbreak of this disease; Methodology used in the analysis; Implications of the results.

For five years, OpenPiton has provided hardware designs, build and verification scripts, and other infrastructure to enable efficient, detailed research into manycores and systems-on-chip. It enables open-source hardware development through its open design and support of a plethora of open simulators and CAD tools. OpenPiton was first designed to perform cutting-edge computer architecture research at Princeton University and opening it up to the public has led to thousands of downloads and numerous academic publications spanning many subfields within computing. In this article, we share some of the lessons learned during the development of OpenPiton, provide examples of how OpenPiton has been used to efficiently test novel research ideas, and discuss how OpenPiton has evolved due to its open development and feedback from the open-source community. [ABSTRACT FROM AUTHOR]

Francisella tularensis is classified as a Class A bioterrorism agent by the U.S. government due to its high virulence and the ease with which it can be spread as an aerosol. It is a facultative intracellular pathogen and the causative agent of tularemia. Ciprofloxacin (Cipro) is a broad spectrum antibiotic effective against Gram-positive and Gram-negative bacteria. Increased Cipro resistance in pathogenic microbes is of serious concern when considering options for medical treatment of bacterial infections. Identification of genes and loci that are associated with Ciprofloxacin resistance will help advance the understanding of resistance mechanisms and may, in the future, provide better treatment options for patients. It may also provide information for development of assays that can rapidly identify Cipro-resistant isolates of this pathogen. In this study, we selected a large number of F. tularensis live vaccine strain (LVS) isolates that survived in progressively higher Ciprofloxacin concentrations, screened the isolates using a whole genome F. tularensis LVS tiling microarray and Illumina sequencing, and identified both known and novel mutations associated with resistance. Genes containing mutations encode DNA gyrase subunit A, a hypothetical protein, an asparagine synthase, a sugar transamine/perosamine synthetase and others. Structural modeling performed on these proteins provides insights into the potential function of these proteins and how they might contribute to Cipro resistance mechanisms. [ABSTRACT FROM AUTHOR]

ABSTRACTAn 8-year bioremediation field study was conducted in a trichloroethene (TCE)-contaminated, highly indurated (i.e., hard), recharge-limited (i.e., contains little water) conglomerate where common remediation strategies, such as groundwater recirculation and direct push installation of a large well network, could not be used. A tracer test using isotopically distinct water from the Hetch Hetchy Reservoir indicated that remediation fluids mainly flowed through fractures and sand lenses in the conglomerate. This was confirmed during in situ bioremediation of the site, in whichDehalococcoides(from a bioaugmentation culture) and volatile fatty acids (from injection of lactate) were the most accurate indicators of transport between wells. Some contaminants were also displaced out of the area due to injection of tracer water. Despite these difficulties, dissolved contaminant mass decreased by an estimated 80% by the end of the test, reaching the lowest values ever recorded at this site. Furthermore, the persistence of ethene 4 years after bioaugmentation suggests that the dechlorinating capacity of the remaining microbial community is comparable to the matrix diffusion of TCE into the dissolved phase. [ABSTRACT FROM PUBLISHER]

The pyrrolo[2,1-c][1,4] benzodiazepines (PBDs) are a family of sequence-selective, minor-groove binding DNA-interactive agents that covalently attach to guanine residues. A recent publication in this journal (Raju et al, PloS One, 2012, 7, 4, e35920) reported that two PBD molecules were observed to bind with high affinity to the telomeric quadruplex of Tetrahymena glaucoma based on Electrospray Ionisation Mass Spectrometry (ESI-MS), Circular Dichroism, UV-Visible and Fluorescence spectroscopy data. This was a surprising result given the close 3-dimensional shape match between the structure of all PBD molecules and the minor groove of duplex DNA, and the completely different 3-dimensional structure of quadruplex DNA. Therefore, we evaluated the interaction of eight PBD molecules of diverse structure with a range of parallel, antiparallel and mixed DNA quadruplexes using DNA Thermal Denaturation, Circular Dichroism and Molecular Dynamics Simulations. Those PBD molecules without large C8-substitutents had an insignificant affinity for the eight quadruplex types, although those with large π-system-containing C8-substituents (as with the compounds evaluated by Raju and co-workers) were found to interact to some extent. Our molecular dynamics simulations support the likelihood that molecules of this type, including those examined by Raju and co-workers, interact with quadruplex DNA through their C8-substituents rather than the PBD moiety itself. It is important for the literature to be clear on this matter, as the mechanism of action of these agents will be under close scrutiny in the near future due to the growing number of PBD-based agents entering the clinic as both single-agents and as components of antibody-drug conjugates (ADCs). [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The article discusses the criteria used for validating methods in microbial forensics. According to the authors, validation is described as the process that assesses the ability of procedures to obtain reliable results under define conditions and identifies aspects of the analysis that must be monitored and controlled. The validation has four categories including sample collection and preservation, extraction, analysis and interpretation of results. It must be considered dynamic to assess periodically the impact of knowledge and findings and to assess material modifications made to existing methods and procedures.

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 of 12 subgroups. Reconstruction of the pagA gene also showed a unique SNP that defines a new lineage for B. anthracis. [ABSTRACT FROM AUTHOR]

Ten variable-number tandem-repeat (VNTR) regions identified within the complete genomic sequence of Clostridium botulinum strain ATCC 3502 were used to characterize 59 C. botulinum strains of the botulism neurotoxin A1 (BoNT/A1) to BoNT/A4 (BoNT/A1-A4) subtypes to determine their ability to discriminate among the serotype A strains. Two strains representing each of the C. botulinum serotypes B to G, including five bivalent strains, and two strains of the closely related species Clostridium sporogenes were also tested. Amplified fragment length polymorphism analyses revealed the genetic diversity among the serotypes and the high degree of similarity among many of the BoNT/A1 strains. The 10 VNTR markers amplified fragments within all of the serotype A strains but were less successful with strains of other serotypes. The composite multiple-locus VNTR analysis of the 59 BoNT/A1-A4 strains and 3 bivalent B strains identified 38 different genotypes. Thirty genotypes were identified among the 53 BoNT/A1 and BoNT/A1(B) strains, demonstrating discrimination below the subtype level. Contaminating DNA within crude toxin preparations of three BoNT/A subtypes (BoNT/A1 to BoNT/A3) also supported amplification of all of the VNTR regions. These markers provide clinical and forensics laboratories with a rapid, highly discriminatory tool to distinguish among C. botulinum BoNT/A1 strains for investigations of botulism outbreaks. [ABSTRACT FROM AUTHOR]

Burkholderia pseudomallei is a biothreat agent and an important natural pathogen, causing melioidosis in humans and animals. A type III secretion system (TTSS-3) has been shown to be critical for virulence. Because TTSS components from other pathogens have been used successfully as diagnostic agents and as experimental vaccines, it was investigated whether this was the case for BipB, BipC and BipD, components of B. pseudomallei's TTSS-3. The sequences of BipB, BipC and BipD were found to be highly conserved among B. pseudomallei and B. mallei isolates. A collection of monoclonal antibodies (mAbs) specific for each Bip protein was obtained. Most recognized both native and denatured Bip protein. Burkholderia pseudomallei or B. mallei did not express detectable BipB or BipD under the growth conditions used. However, anti-BipD mAbs did recognize the TTSS needle structures of a Shigella strain engineered to express BipD. The authors did not find that BipB, BipC or BipD are protective antigens because vaccination of mice with any single protein did not result in protection against experimental melioidosis. Enzyme-linked immunosorbent assay (ELISA) studies showed that human melioidosis patients had antibodies to BipB and BipD. However, these ELISAs had low diagnostic accuracy in endemic regions, possibly due to previous patient exposure to B. pseudomallei. [ABSTRACT FROM AUTHOR]

DNA from over 300 Bacillus thuringiensis, Bacillus cereus, and Bacillus anthracis isolates was analyzed by fluorescent amplified fragment length polymorphism (AFLP). B. thuringiensis and B. cereus isolates were from diverse sources and locations, including soil, clinical isolates and food products causing diarrheal and emetic outbreaks, and type strains from the American Type Culture Collection, and over 200 B. thuringiensis isolates representing 36 serovars or subspecies were from the U.S. Department of Agriculture collection. Twenty-four diverse B. anthracis isolates were also included. Phylogenetic analysis of AFLP data revealed extensive diversity within B. thuringiensis and B. cereus compared to the monomorphic nature of B. anthracis. All of the B. anthracis strains were more closely related to each other than to any other Bacillus isolate, while B. cereus and B. thuringiensis strains populated the entire tree. Ten distinct branches were defined, with many branches containing both B. cereus and B. thuringiensis isolates. A single branch contained all the B. anthracis isolates plus an unusual B. thuringiensis isolate that is pathogenic in mice. In contrast, B. thuringiensis subsp, kurstaki (ATCC 33679) and other isolates used to prepare insecticides mapped distal to the B. anthracis isolates. The interspersion of B. cereus and B. thuringiensis isolates within the phylogenetic tree suggests that phenotypic traits used to distinguish between these two species do not reflect the genomic content of the different isolates and that horizontal gene transfer plays an important role in establishing the phenotype of each of these microbes. B. thuringiensis isolates of a particular subspecies tended to cluster together. [ABSTRACT FROM AUTHOR]

The three species of the group 1 bacilli, Bacillus anthracis, B. cereus, and B. thuringiensis, are genetically very closely related. All inhabit soil habitats but exhibit different phenotypes. B. anthracis is the causative agent of anthrax and is phylogenetically monomorphic, while B. cereus and B. thuringiensis are genetically more diverse. An amplified fragment length polymorphism analysis described here demonstrates genetic diversity among a collection of non-anthrax-causing Bacillus species, some of which show significant similarity to B. anthracis. Suppression subtractive hybridization was then used to characterize the genomic differences that distinguish three of the non-anthrax-causing bacilli from B. anthracis Ames. Ninety-three DNA sequences that were present in B. anthracis but absent from the non-anthrax-causing Bacillus genomes were isolated. Furthermore, 28 of these sequences were not found in a collection of 10 non-anthrax-causing Bacillus species but were present in all members of a representative collection of B. anthracis strains. These sequences map to distinct loci on the B. anthracis genome and can be assayed simultaneously in multiplex PCR assays for rapid and highly specific DNA-based detection of B. anthracis. [ABSTRACT FROM AUTHOR]

Examines Norwegian Bacillus cereus and Bacillus thuringiensis soil isolates and Bacillus anthracis strains by using fluorescent amplified fragment length polymorphism (AFLP). Genetic diversity among different Bacillus cereus and Bacillus thuringiensis environmental isolates; Causal agent of anthrax; Three aspects to automated AFLP analysis.

Reports on a study which developed a method used to extract and purify DNA from soils for in-the-field use. Examination of microbial community diversity in soil; Details on the usage of a PCR analysis; Methodology used to conduct the study; Results of the study.

Presents a study pertaining to the development of a bacterial biosensor which tested contaminated water and soil for benzene, toluene and similar compounds. Materials and methods used in the study; Results of the study; Discussion based on the results.

Lytic proteins encoded by bacterial genomes have been implicated in cell wall biosynthesis and recycling. The Bacillus cereus E33L ampD gene encodes a putative N-acetylmuramoyl-L-alanine amidase. This gene, expressed in vitro, produced a very stable, highly active lytic protein. Very low concentrations rapidly and efficiently lyse vegetative Bacillus anthracis cells. [ABSTRACT FROM AUTHOR]

Bacillus cereus pneumonia is unusual in nonimmunocompromised hosts. We describe fatal cases in 2 metalworkers and the associated investigation. Anthrax toxin genes were identified in B. cereus isolates from both patients using polymerase chain reaction. Finding anthrax toxin genes in non-Bacillus anthracis isolates has, to our knowledge, only been reported once previously. [ABSTRACT FROM AUTHOR]

Despite emerging targeted and immunotherapy treatments, no monoclonal antibodies or antibody-drug conjugates (ADCs) directly targeting tumor cells are currently approved for melanoma therapy. The tumor-associated antigen chondroitin sulphate proteoglycan 4 (CSPG4), a neural crest glycoprotein over-expressed on 70% of melanomas, contributes to proliferative signaling pathways, but despite highly tumor-selective expression it has not yet been targeted using ADCs. We developed a novel ADC comprising an anti-CSPG4 antibody linked to a DNA minor groove-binding agent belonging to the novel pyrridinobenzodiazepine (PDD) class. Unlike conventional DNA-interactive pyrrolobenzodiazepine (PBD) dimer payloads that cross-link DNA, PDD-based payloads are mono-alkylating agents but have similar efficacy and substantially enhanced tolerability profiles compared to PBD-based cross-linkers. We investigated the anti-tumor activity and safety of the anti-CSPG4-(PDD) ADC in vitro and in human melanoma xenografts. Anti-CSPG4-(PDD) inhibited CSPG4-expressing melanoma cell growth and colony formation and triggered apoptosis in vitro at low nanomolar to picomolar concentrations without off-target Fab-mediated or Fc-mediated toxicity. Anti-CSPG4-(PDD) restricted xenograft growth in vivo at 2 mg/kg doses. One 5 mg/kg injection triggered tumor regression in the absence of overt toxic effects or of acquired residual tumor cell resistance. This anti-CSPG4-(PDD) can deliver a highly cytotoxic DNA mono-alkylating payload to CSPG4-expressing tumors at doses tolerated in vivo. [ABSTRACT FROM AUTHOR]

Bacillus anthracis is the potentially lethal etiologic agent of anthrax disease, and is a significant concern in the realm of biodefense. One of the cornerstones of an effective biodefense strategy is the ability to detect infectious agents with a high degree of sensitivity and specificity in the context of a complex sample background. The nature of the B. anthracis genome, however, renders specific detection difficult, due to close homology with B. cereus and B. thuringiensis. We therefore elected to determine the efficacy of next-generation sequencing analysis and microarrays for detection of B. anthracis in an environmental background. We applied next-generation sequencing to titrated genome copy numbers of B. anthracis in the presence of background nucleic acid extracted from aerosol and soil samples. We found next-generation sequencing to be capable of detecting as few as 10 genomic equivalents of B. anthracis DNA per nanogram of background nucleic acid. Detection was accomplished by mapping reads to either a defined subset of reference genomes or to the full GenBank database. Moreover, sequence data obtained from B. anthracis could be reliably distinguished from sequence data mapping to either B. cereus or B. thuringiensis. We also demonstrated the efficacy of a microbial census microarray in detecting B. anthracis in the same samples, representing a cost-effective and high-throughput approach, complementary to next-generation sequencing. Our results, in combination with the capacity of sequencing for providing insights into the genomic characteristics of complex and novel organisms, suggest that these platforms should be considered important components of a biosurveillance strategy. [ABSTRACT FROM AUTHOR]

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 97-27and 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. [ABSTRACT FROM AUTHOR]