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A Mobile Device for Monitoring the Biological Purity of Air and Liquid Samples. SENSORS 2021; 21:s21103570. [PMID: 34065526 PMCID: PMC8161204 DOI: 10.3390/s21103570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 05/14/2021] [Accepted: 05/18/2021] [Indexed: 11/16/2022]
Abstract
A detector for identifying potential bacterial hazards in the air was designed and created in the Military Institute of Chemistry and Radiometry in the framework of the project FLORABO. The presence of fungi and bacteria in the air can affect the health of people in a given room. The need to control the amount of microorganisms, both in terms of quantity and quality, applies to both hospitals and offices. The device is based on the fluorescence spectroscopy analysis of the sample and then these results were compared to the resulting spectrogram database, which includes the standard curves obtained in the laboratory for selected bacteria. The measurements provide information about the presence, the type, and the approximate concentration of bacteria in the sample. The spectra were collected at different excitation wavelengths, and the waveforms are specific for each of the strains. It also takes under analysis the signal intensities of the different spectra (not only shape a maximum of the peak) so that the concentration of bacteria in the sample being tested can be determined. The device was tested in the laboratory with concentrations ranging from 10 to 108 cells/mL. Additionally, the detector can distinguish between the vegetative forms of spores of the bacteria.
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The Food Poisoning Toxins of Bacillus cereus. Toxins (Basel) 2021; 13:toxins13020098. [PMID: 33525722 PMCID: PMC7911051 DOI: 10.3390/toxins13020098] [Citation(s) in RCA: 113] [Impact Index Per Article: 37.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 01/14/2021] [Accepted: 01/25/2021] [Indexed: 12/13/2022] Open
Abstract
Bacillus cereus is a ubiquitous soil bacterium responsible for two types of food-associated gastrointestinal diseases. While the emetic type, a food intoxication, manifests in nausea and vomiting, food infections with enteropathogenic strains cause diarrhea and abdominal pain. Causative toxins are the cyclic dodecadepsipeptide cereulide, and the proteinaceous enterotoxins hemolysin BL (Hbl), nonhemolytic enterotoxin (Nhe) and cytotoxin K (CytK), respectively. This review covers the current knowledge on distribution and genetic organization of the toxin genes, as well as mechanisms of enterotoxin gene regulation and toxin secretion. In this context, the exceptionally high variability of toxin production between single strains is highlighted. In addition, the mode of action of the pore-forming enterotoxins and their effect on target cells is described in detail. The main focus of this review are the two tripartite enterotoxin complexes Hbl and Nhe, but the latest findings on cereulide and CytK are also presented, as well as methods for toxin detection, and the contribution of further putative virulence factors to the diarrheal disease.
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Microarray experiments and factors which affect their reliability. Biol Direct 2015; 10:46. [PMID: 26335588 PMCID: PMC4559324 DOI: 10.1186/s13062-015-0077-2] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Accepted: 08/24/2015] [Indexed: 12/12/2022] Open
Abstract
Oligonucleotide microarrays belong to the basic tools of molecular biology and allow for simultaneous assessment of the expression level of thousands of genes. Analysis of microarray data is however very complex, requiring sophisticated methods to control for various factors that are inherent to the procedures used. In this article we describe the individual steps of a microarray experiment, highlighting important elements and factors that may affect the processes involved and that influence the interpretation of the results. Additionally, we describe methods that can be used to estimate the influence of these factors, and to control the way in which they affect the expression estimates. A comprehensive understanding of the experimental protocol used in a microarray experiment aids the interpretation of the obtained results. By describing known factors which affect expression estimates this article provides guidelines for appropriate quality control and pre-processing of the data, additionally applicable to other transcriptome analysis methods that utilize similar sample handling protocols.
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Leski TA, Lin B, Malanoski AP, Stenger DA. Application of resequencing microarrays in microbial detection and characterization. Future Microbiol 2012; 7:625-37. [PMID: 22568717 DOI: 10.2217/fmb.12.30] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Microarrays are powerful, highly parallel assays that are transforming microbiological diagnostics and research. The adaptation of microarray-based resequencing technology for microbial detection and characterization resulted in the development of a number assays that have unique advantages over other existing technologies. This technological platform seems to be especially useful for sensitive and high-resolution multiplexed diagnostics for clinical syndromes with similar symptoms, screening environmental samples for biothreat agents, as well as genotyping and whole-genome analysis of single pathogens.
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Affiliation(s)
- Tomasz A Leski
- Center for Bio/Molecular Science & Engineering, Naval Research Laboratory, SW, Washington, DC 20375, USA.
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5
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Genetic variation and linkage disequilibrium in Bacillus anthracis. Sci Rep 2011; 1:169. [PMID: 22355684 PMCID: PMC3240990 DOI: 10.1038/srep00169] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2011] [Accepted: 11/03/2011] [Indexed: 12/27/2022] Open
Abstract
We performed whole-genome amplification followed by hybridization of custom-designed resequencing arrays to resequence 303 kb of genomic sequence from a worldwide panel of 39 Bacillus anthracis strains. We used an efficient algorithm contained within a custom software program, UniqueMER, to identify and mask repetitive sequences on the resequencing array to reduce false-positive identification of genetic variation, which can arise from cross-hybridization. We discovered a total of 240 single nucleotide variants (SNVs) and showed that B. anthracis strains have an average of 2.25 differences per 10,000 bases in the region we resequenced. Common SNVs in this region are found to be in complete linkage disequilibrium. These patterns of variation suggest there has been little if any historical recombination among B. anthracis strains since the origin of the pathogen. This pattern of common genetic variation suggests a framework for recognizing new or genetically engineered strains.
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Didelot X, Bowden R, Street T, Golubchik T, Spencer C, McVean G, Sangal V, Anjum MF, Achtman M, Falush D, Donnelly P. Recombination and population structure in Salmonella enterica. PLoS Genet 2011; 7:e1002191. [PMID: 21829375 PMCID: PMC3145606 DOI: 10.1371/journal.pgen.1002191] [Citation(s) in RCA: 108] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2011] [Accepted: 06/04/2011] [Indexed: 01/22/2023] Open
Abstract
Salmonella enterica is a bacterial pathogen that causes enteric fever and gastroenteritis in humans and animals. Although its population structure was long described as clonal, based on high linkage disequilibrium between loci typed by enzyme electrophoresis, recent examination of gene sequences has revealed that recombination plays an important evolutionary role. We sequenced around 10% of the core genome of 114 isolates of enterica using a resequencing microarray. Application of two different analysis methods (Structure and ClonalFrame) to our genomic data allowed us to define five clear lineages within S. enterica subspecies enterica, one of which is five times older than the other four and two thirds of the age of the whole subspecies. We show that some of these lineages display more evidence of recombination than others. We also demonstrate that some level of sexual isolation exists between the lineages, so that recombination has occurred predominantly between members of the same lineage. This pattern of recombination is compatible with expectations from the previously described ecological structuring of the enterica population as well as mechanistic barriers to recombination observed in laboratory experiments. In spite of their relatively low level of genetic differentiation, these lineages might therefore represent incipient species.
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Affiliation(s)
- Xavier Didelot
- Department of Statistics, Oxford University, Oxford, United Kingdom
| | - Rory Bowden
- Department of Statistics, Oxford University, Oxford, United Kingdom
- Wellcome Trust Centre for Human Genetics, Oxford University, Oxford, United Kingdom
| | - Teresa Street
- Department of Statistics, Oxford University, Oxford, United Kingdom
| | - Tanya Golubchik
- Department of Statistics, Oxford University, Oxford, United Kingdom
| | - Chris Spencer
- Wellcome Trust Centre for Human Genetics, Oxford University, Oxford, United Kingdom
| | - Gil McVean
- Department of Statistics, Oxford University, Oxford, United Kingdom
- Wellcome Trust Centre for Human Genetics, Oxford University, Oxford, United Kingdom
| | - Vartul Sangal
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom
| | - Muna F. Anjum
- Veterinary Laboratories Agency, Addlestone, United Kingdom
| | - Mark Achtman
- Environmental Research Institute and Department of Microbiology, University College Cork, Cork, Ireland
| | - Daniel Falush
- Environmental Research Institute and Department of Microbiology, University College Cork, Cork, Ireland
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Peter Donnelly
- Department of Statistics, Oxford University, Oxford, United Kingdom
- Wellcome Trust Centre for Human Genetics, Oxford University, Oxford, United Kingdom
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7
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Bacterial population genomics and infectious disease diagnostics. Trends Biotechnol 2010; 28:611-8. [PMID: 20961641 DOI: 10.1016/j.tibtech.2010.09.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2010] [Revised: 09/03/2010] [Accepted: 09/07/2010] [Indexed: 01/14/2023]
Abstract
New sequencing technologies have made the production of bacterial genome sequences increasingly easy, and it can be confidently forecasted that vast genomic databases will be generated in the next few years. Here, we detail how collections of bacterial genomes from a particular species (population genomics libraries) have already been used to improve the design of several diagnostic assays for bacterial pathogens. Genome sequencing itself is also becoming more commonly used for epidemiological, forensic and clinical investigations. There is an opportunity for the further development of bioinformatic tools to bring even further value to bacterial diagnostic genomics.
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Chen PE, Willner KM, Butani A, Dorsey S, George M, Stewart A, Lentz SM, Cook CE, Akmal A, Price LB, Keim PS, Mateczun A, Brahmbhatt TN, Bishop-Lilly KA, Zwick ME, Read TD, Sozhamannan S. Rapid identification of genetic modifications in Bacillus anthracis using whole genome draft sequences generated by 454 pyrosequencing. PLoS One 2010; 5:e12397. [PMID: 20811637 PMCID: PMC2928293 DOI: 10.1371/journal.pone.0012397] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2010] [Accepted: 07/27/2010] [Indexed: 12/26/2022] Open
Abstract
Background The anthrax letter attacks of 2001 highlighted the need for rapid identification of biothreat agents not only for epidemiological surveillance of the intentional outbreak but also for implementing appropriate countermeasures, such as antibiotic treatment, in a timely manner to prevent further casualties. It is clear from the 2001 cases that survival may be markedly improved by administration of antimicrobial therapy during the early symptomatic phase of the illness; i.e., within 3 days of appearance of symptoms. Microbiological detection methods are feasible only for organisms that can be cultured in vitro and cannot detect all genetic modifications with the exception of antibiotic resistance. Currently available immuno or nucleic acid-based rapid detection assays utilize known, organism-specific proteins or genomic DNA signatures respectively. Hence, these assays lack the ability to detect novel natural variations or intentional genetic modifications that circumvent the targets of the detection assays or in the case of a biological attack using an antibiotic resistant or virulence enhanced Bacillus anthracis, to advise on therapeutic treatments. Methodology/Principal Findings We show here that the Roche 454-based pyrosequencing can generate whole genome draft sequences of deep and broad enough coverage of a bacterial genome in less than 24 hours. Furthermore, using the unfinished draft sequences, we demonstrate that unbiased identification of known as well as heretofore-unreported genetic modifications that include indels and single nucleotide polymorphisms conferring antibiotic and phage resistances is feasible within the next 12 hours. Conclusions/Significance Second generation sequencing technologies have paved the way for sequence-based rapid identification of both known and previously undocumented genetic modifications in cultured, conventional and newly emerging biothreat agents. Our findings have significant implications in the context of whole genome sequencing-based routine clinical diagnostics as well as epidemiological surveillance of natural disease outbreaks caused by bacterial and viral agents.
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Affiliation(s)
- Peter E. Chen
- Naval Medical Research Center, Biological Defense Research Directorate, Silver Spring, Maryland, United States of America
| | - Kristin M. Willner
- Naval Medical Research Center, Biological Defense Research Directorate, Silver Spring, Maryland, United States of America
| | - Amy Butani
- Naval Medical Research Center, Biological Defense Research Directorate, Silver Spring, Maryland, United States of America
| | - Shakia Dorsey
- Naval Medical Research Center, Biological Defense Research Directorate, Silver Spring, Maryland, United States of America
| | - Matroner George
- Naval Medical Research Center, Biological Defense Research Directorate, Silver Spring, Maryland, United States of America
| | - Andrew Stewart
- Naval Medical Research Center, Biological Defense Research Directorate, Silver Spring, Maryland, United States of America
| | - Shannon M. Lentz
- Naval Medical Research Center, Biological Defense Research Directorate, Silver Spring, Maryland, United States of America
| | - Christopher E. Cook
- Naval Medical Research Center, Biological Defense Research Directorate, Silver Spring, Maryland, United States of America
| | - Arya Akmal
- Naval Medical Research Center, Biological Defense Research Directorate, Silver Spring, Maryland, United States of America
| | - Lance B. Price
- Translational Genomics Research Institute, Flagstaff, Arizona, United States of America
| | - Paul S. Keim
- Translational Genomics Research Institute, Flagstaff, Arizona, United States of America
- Northern Arizona University, Flagstaff, Arizona, Unites States of America
| | - Alfred Mateczun
- Naval Medical Research Center, Biological Defense Research Directorate, Silver Spring, Maryland, United States of America
| | - Trupti N. Brahmbhatt
- Naval Medical Research Center, Biological Defense Research Directorate, Silver Spring, Maryland, United States of America
| | - Kimberly A. Bishop-Lilly
- Naval Medical Research Center, Biological Defense Research Directorate, Silver Spring, Maryland, United States of America
| | - Michael E. Zwick
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Timothy D. Read
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, United States of America
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Shanmuga Sozhamannan
- Naval Medical Research Center, Biological Defense Research Directorate, Silver Spring, Maryland, United States of America
- * E-mail:
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Bruce CK, Smith M, Rahman F, Liu ZF, McMullan DJ, Ball S, Hartley J, Kroos MA, Heptinstall L, Reuser AJ, Rolfs A, Hendriksz C, Kelly DA, Barrett TG, MacDonald F, Maher ER, Gissen P. Design and validation of a metabolic disorder resequencing microarray (BRUM1). Hum Mutat 2010; 31:858-65. [DOI: 10.1002/humu.21261] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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10
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Mulle JG, Patel VC, Warren ST, Hegde MR, Cutler DJ, Zwick ME. Empirical evaluation of oligonucleotide probe selection for DNA microarrays. PLoS One 2010; 5:e9921. [PMID: 20360966 PMCID: PMC2847945 DOI: 10.1371/journal.pone.0009921] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2009] [Accepted: 12/04/2009] [Indexed: 12/04/2022] Open
Abstract
DNA-based microarrays are increasingly central to biomedical research. Selecting oligonucleotide sequences that will behave consistently across experiments is essential to the design, production and performance of DNA microarrays. Here our aim was to improve on probe design parameters by empirically and systematically evaluating probe performance in a multivariate context. We used experimental data from 19 array CGH hybridizations to assess the probe performance of 385,474 probes tiled in the Duchenne muscular dystrophy (DMD) region of the X chromosome. Our results demonstrate that probe melting temperature, single nucleotide polymorphisms (SNPs), and homocytosine motifs all have a strong effect on probe behavior. These findings, when incorporated into future microarray probe selection algorithms, may improve microarray performance for a wide variety of applications.
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Affiliation(s)
- Jennifer G Mulle
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, United States of America.
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Dworzanski JP, Dickinson DN, Deshpande SV, Snyder AP, Eckenrode BA. Discrimination and Phylogenomic Classification of Bacillus anthracis-cereus-thuringiensis Strains Based on LC-MS/MS Analysis of Whole Cell Protein Digests. Anal Chem 2009; 82:145-55. [DOI: 10.1021/ac9015648] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jacek P. Dworzanski
- Science Applications International Corporation, Aberdeen Proving Ground, Maryland 21010-0068, Northrop Grumman Electronic Systems, Baltimore, Maryland 21203, Science and Technology Corporation, Edgewood, Maryland 21040, U.S. Army Edgewood Chemical Biological Center, Aberdeen Proving Ground, Maryland 21010-5424, and FBI Counterterrorism and Forensic Science Research Unit, Quantico, Virginia 22135
| | - Danielle N. Dickinson
- Science Applications International Corporation, Aberdeen Proving Ground, Maryland 21010-0068, Northrop Grumman Electronic Systems, Baltimore, Maryland 21203, Science and Technology Corporation, Edgewood, Maryland 21040, U.S. Army Edgewood Chemical Biological Center, Aberdeen Proving Ground, Maryland 21010-5424, and FBI Counterterrorism and Forensic Science Research Unit, Quantico, Virginia 22135
| | - Samir V. Deshpande
- Science Applications International Corporation, Aberdeen Proving Ground, Maryland 21010-0068, Northrop Grumman Electronic Systems, Baltimore, Maryland 21203, Science and Technology Corporation, Edgewood, Maryland 21040, U.S. Army Edgewood Chemical Biological Center, Aberdeen Proving Ground, Maryland 21010-5424, and FBI Counterterrorism and Forensic Science Research Unit, Quantico, Virginia 22135
| | - A. Peter Snyder
- Science Applications International Corporation, Aberdeen Proving Ground, Maryland 21010-0068, Northrop Grumman Electronic Systems, Baltimore, Maryland 21203, Science and Technology Corporation, Edgewood, Maryland 21040, U.S. Army Edgewood Chemical Biological Center, Aberdeen Proving Ground, Maryland 21010-5424, and FBI Counterterrorism and Forensic Science Research Unit, Quantico, Virginia 22135
| | - Brian A. Eckenrode
- Science Applications International Corporation, Aberdeen Proving Ground, Maryland 21010-0068, Northrop Grumman Electronic Systems, Baltimore, Maryland 21203, Science and Technology Corporation, Edgewood, Maryland 21040, U.S. Army Edgewood Chemical Biological Center, Aberdeen Proving Ground, Maryland 21010-5424, and FBI Counterterrorism and Forensic Science Research Unit, Quantico, Virginia 22135
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12
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Sela-Abramovich S, Chitlaru T, Gat O, Grosfeld H, Cohen O, Shafferman A. Novel and unique diagnostic biomarkers for Bacillus anthracis infection. Appl Environ Microbiol 2009; 75:6157-67. [PMID: 19648366 PMCID: PMC2753070 DOI: 10.1128/aem.00766-09] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2009] [Accepted: 07/22/2009] [Indexed: 01/28/2023] Open
Abstract
A search for bacterium-specific biomarkers in peripheral blood following infection with Bacillus anthracis was carried out with rabbits, using a battery of specific antibodies generated by DNA vaccination against 10 preselected highly immunogenic bacterial antigens which were identified previously by a genomic/proteomic/serologic screen of the B. anthracis secretome. Detection of infection biomarkers in the circulation of infected rabbits could be achieved only after removal of highly abundant serum proteins by chromatography using a random-ligand affinity column. Besides the toxin component protective antigen, the following three secreted proteins were detected in the circulation of infected animals: the chaperone and protease HtrA (BA3660), an NlpC/P60 endopeptidase (BA1952), and a protein of unknown function harboring two SH3 (Src homology 3) domains (BA0796). The three proteins could be detected in plasma samples from infected animals exhibiting 10(3) to 10(5) CFU/ml blood and also in standard blood cultures at 3 to 6 h post-bacterial inoculation at a bacteremic level as low as 10(3) CFU/ml. Furthermore, the three biomarkers appear to be present only in the secretome of B. anthracis, not in those of the related pathogens B. thuringiensis and B. cereus. To the best of our knowledge, this is the first report of direct detection of B. anthracis-specific proteins, other than the toxin components, in the circulation of infected animals.
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Affiliation(s)
- Sagit Sela-Abramovich
- Department of Biochemistry and Molecular Genetics, Life Science Research Israel Ltd, 2 Ness-Ziona 74100, Israel
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Passalacqua KD, Varadarajan A, Byrd B, Bergman NH. Comparative transcriptional profiling of Bacillus cereus sensu lato strains during growth in CO2-bicarbonate and aerobic atmospheres. PLoS One 2009; 4:e4904. [PMID: 19295911 PMCID: PMC2654142 DOI: 10.1371/journal.pone.0004904] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2009] [Accepted: 02/17/2009] [Indexed: 11/19/2022] Open
Abstract
Background Bacillus species are spore-forming bacteria that are ubiquitous in the environment and display a range of virulent and avirulent phenotypes. This range is particularly evident in the Bacillus cereus sensu lato group; where closely related strains cause anthrax, food-borne illnesses, and pneumonia, but can also be non-pathogenic. Although much of this phenotypic range can be attributed to the presence or absence of a few key virulence factors, there are other virulence-associated loci that are conserved throughout the B. cereus group, and we hypothesized that these genes may be regulated differently in pathogenic and non-pathogenic strains. Methodology/Principal Findings Here we report transcriptional profiles of three closely related but phenotypically unique members of the Bacillus cereus group—a pneumonia-causing B. cereus strain (G9241), an attenuated strain of B. anthracis (Sterne 34F2), and an avirulent B. cereus strain (10987)—during exponential growth in two distinct atmospheric environments: 14% CO2/bicarbonate and ambient air. We show that the disease-causing Bacillus strains undergo more distinctive transcriptional changes between the two environments, and that the expression of plasmid-encoded virulence genes was increased exclusively in the CO2 environment. We observed a core of conserved metabolic genes that were differentially expressed in all three strains in both conditions. Additionally, the expression profiles of putative virulence genes in G9241 suggest that this strain, unlike Bacillus anthracis, may regulate gene expression with both PlcR and AtxA transcriptional regulators, each acting in a different environment. Conclusions/Significance We have shown that homologous and even identical genes within the genomes of three closely related members of the B. cereus sensu lato group are in some instances regulated very differently, and that these differences can have important implications for virulence. This study provides insights into the evolution of the B. cereus group, and highlights the importance of looking beyond differences in gene content in comparative genomics studies.
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Affiliation(s)
- Karla D. Passalacqua
- School of Biology, Georgia Institute of Technology, Atlanta, Georgia, United States of America
| | - Anjana Varadarajan
- School of Biology, Georgia Institute of Technology, Atlanta, Georgia, United States of America
| | - Benjamin Byrd
- School of Biology, Georgia Institute of Technology, Atlanta, Georgia, United States of America
| | - Nicholas H. Bergman
- School of Biology, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- Electro-Optical Systems Laboratory, Georgia Tech Research Institute, Atlanta, Georgia, United States of America
- * E-mail:
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