Evaluation of the Efficacy of Methyl Bromide in the Decontamination of Building and Interior Materials Contaminated with Bacillus anthracis Spores

ABSTRACTThe primary goal of this study was to determine the conditions required for the effective inactivation ofBacillus anthracisspores on materials by using methyl bromide (MeBr) gas. Another objective was to obtain comparative decontamination efficacy data with three avirulent microorganisms to assess their potential for use as surrogates forB. anthracisAmes. Decontamination tests were conducted with spores ofB. anthracisAmes andGeobacillus stearothermophilus,B. anthracisNNR1Δ1, andB. anthracisSterne inoculated onto six different materials. Experimental variables included temperature, relative humidity (RH), MeBr concentration, and contact time. MeBr was found to be an effective decontaminant under a number of conditions. This study highlights the important role that RH has when fumigation is performed with MeBr. There were no tests in which a ≥6-log10reduction (LR) ofB. anthracisAmes was achieved on all materials when fumigation was done at 45% RH. At 75% RH, an increase in the temperature, the MeBr concentration, or contact time generally improved the efficacy of fumigation with MeBr. This study provides new information for the effective use of MeBr at temperatures and RH levels lower than those that have been recommended previously. The study also provides data to assist with the selection of an avirulent surrogate forB. anthracisAmes spores when additional tests with MeBr are conducted.

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Fast and Sensitive Detection of Bacillus anthracis Spores by Immunoassay

Applied and Environmental Microbiology ◽

10.1128/aem.01282-12 ◽

2012 ◽

Vol 78 (18) ◽

pp. 6491-6498 ◽

Cited By ~ 24

Author(s):

Nathalie Morel ◽

Hervé Volland ◽

Julie Dano ◽

Patricia Lamourette ◽

Patricia Sylvestre ◽

...

Keyword(s):

Bacillus Anthracis ◽

Electrical Current ◽

Biological Weapons ◽

Meso Scale Discovery ◽

Simple Method ◽

Content Type ◽

Bacillus Anthracis Spores ◽

Luminescent Signal ◽

Sample Purification ◽

Phosphate Buffered Saline

ABSTRACTBacillus anthracisis one of the most dangerous potential biological weapons, and it is essential to develop a rapid and simple method to detectB. anthracisspores in environmental samples. The immunoassay is a rapid and easy-to-use method for the detection ofB. anthracisby means of antibodies directed against surface spore antigens. With this objective in view, we have produced a panel of monoclonal antibodies againstB. anthracisand developed colorimetric and electrochemiluminescence (ECL) immunoassays. Using Meso Scale Discovery ECL technology, which is based on electrochemiluminescence (ECL) detection utilizing a sulfo-Tag label that emits light upon electrochemical stimulation (using a dedicated ECL plate reader, an electrical current is placed across the microplate with electrodes integrated into the bottom of the plate, resulting in a series of electrically induced reactions leading to a luminescent signal), a detection limit ranging between 0.3 × 103and 103CFU/ml (i.e., 30 to 100 spores per test), depending on theB. anthracisstrain assayed, was achieved. In complex matrices (5 mg/ml of soil or simulated powder), the detection level (without any sample purification or concentration) was never altered more than 3-fold compared with the results obtained in phosphate-buffered saline.

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Aerosol and Surface Deposition Characteristics of Two Surrogates for Bacillus anthracis Spores

Applied and Environmental Microbiology ◽

10.1128/aem.02052-16 ◽

2016 ◽

Vol 82 (22) ◽

pp. 6682-6690 ◽

Cited By ~ 7

Author(s):

Alistair H. Bishop ◽

Helen L. Stapleton

Keyword(s):

Bacillus Anthracis ◽

Pathogenic Bacteria ◽

Human Infection ◽

Solid Surfaces ◽

Surface Deposition ◽

Content Type ◽

Hazard Management ◽

Bacillus Anthracis Spores ◽

Air Blower ◽

Set Up

ABSTRACTSpores of an acrystalliferous derivative ofBacillus thuringiensissubsp.kurstaki, termedBtcry−, are morphologically, aerodynamically, and structurally indistinguishable fromBacillus anthracisspores.Btcry− spores were dispersed in a large, open-ended barn together with spores ofBacillus atrophaeussubsp.globigii, a historically used surrogate forBacillus anthracis. Spore suspensions (2 × 1012CFU each ofB. atrophaeussubsp.globigiiandBtcry−) were aerosolized in each of five spray events using a backpack misting device incorporating an air blower; a wind of 4.9 to 7.6 m s−1was also flowing through the barn in the same direction. Filter air samplers were situated throughout the barn to assess the aerosol density of the spores during each release. Trays filled with a surfactant in aqueous buffer were placed on the floor near the filter samplers to assess spore deposition. Spores were also recovered from arrays of solid surfaces (concrete, aluminum, and plywood) that had been laid on the floor and set up as a wall at the end of the barn.B. atrophaeussubsp.globigiispores were found to remain airborne for significantly longer periods, and to be deposited on horizontal surfaces at lower densities, thanBtcry− spores, particularly near the spray source. There was a 6-fold-higher deposition ofBtcry− spores than ofB. atrophaeussubsp.globigiispores on vertical surfaces relative to the surrounding airborne density. This work is relevant for selecting the bestB. anthracissurrogate for the prediction of human exposure, hazard assessment, and hazard management following a malicious release ofB. anthracis.IMPORTANCEThere is concern that pathogenic bacteria could be maliciously disseminated in the air to cause human infection and disruption of normal life. The threat from spore-forming organisms, such as the causative agent of anthrax, is particularly serious. In order to assess the extent of this risk, it is important to have a surrogate organism that can be used to replicate the dispersal characteristics of the threat agent accurately. This work compares the aerosol dispersal and deposition behaviors of the surrogatesBtcry− andB. atrophaeussubsp.globigii.Btcry− spores remained in the air for a shorter time, and were markedly more likely to adhere to vertical surfaces, thanB. atrophaeussubsp.globigiispores.

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Existence of Separate Domains in Lysin PlyG for Recognizing Bacillus anthracis Spores and Vegetative Cells

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00891-12 ◽

2012 ◽

Vol 56 (10) ◽

pp. 5031-5039 ◽

Cited By ~ 25

Author(s):

Hang Yang ◽

Dian-Bing Wang ◽

Qiuhua Dong ◽

Zhiping Zhang ◽

Zongqiang Cui ◽

...

Keyword(s):

Bacillus Anthracis ◽

Catalytic Domain ◽

Vegetative Cells ◽

Content Type ◽

Bacillus Anthracis Spores ◽

Acid Domain ◽

New Biomarkers ◽

First Time ◽

Amino Acid Domain ◽

Spore Forming Bacteria

ABSTRACTAs a potential antimicrobial, the bacteriophage lysin PlyG has been reported to specifically recognizeBacillus anthracisvegetative cells only and to killB. anthracisvegetative cells and its germinating spores. However, how PlyG interacts withB. anthracisspores remains unclear. Herein, a 60-amino-acid domain in PlyG (residues 106 to 165), located mainly in the previously identified catalytic domain, was found able to specifically recognizeB. anthracisspores but not vegetative cells. The exosporium of the spores was found to be the most probable binding target of this domain. This is the first time that a lysin for spore-forming bacteria has been found to have separate domains to recognize spores and vegetative cells, which might help in understanding the coevolution of phages with spore-forming bacteria. Besides providing new biomarkers for developing better assays for identifyingB. anthracisspores, the newly found domain may be helpful in developing PlyG as a preventive antibiotic to reduce the threat of anthrax in suspected exposures toB. anthracisspores.

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Microbicidal Power of Alpha Radiation in Sterilizing Germinating Bacillus anthracis Spores

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01266-13 ◽

2013 ◽

Vol 58 (3) ◽

pp. 1813-1815 ◽

Cited By ~ 3

Author(s):

Johanna Rivera ◽

Alfred Morgenstern ◽

Frank Bruchertseifer ◽

John F. Kearney ◽

Charles L. Turnbough ◽

...

Keyword(s):

Bacillus Anthracis ◽

Dependent Manner ◽

Alpha Radiation ◽

Content Type ◽

Immunodominant Antigen ◽

Spore Killing ◽

Bacillus Anthracis Spores ◽

A Site ◽

Antigen Antibody ◽

Dose Dependent

ABSTRACTRadioimmunotherapy (RIT) takes advantage of the specificity and affinity of the antigen-antibody interaction to deliver microbicidal radioactive nuclides to a site of infection. In this study, we investigated the microbicidal properties of an alpha particle-emitting213Bi-labeled monoclonal antibody (MAb), EA2-1 (213Bi-EA2-1), that binds to the immunodominant antigen onBacillus anthracisspores. Our results showed that dormant spores were resistant to213Bi-EA2-1. Significant spore killing was observed following treatment with EA2-1 labeled with 300 μCi213Bi; however, this effect was not dependent on the MAb. In contrast, when spores were germinating,213Bi-EA2-1 mediated MAb-specific killing in a dose-dependent manner. Dormant spores are very resistant to RIT, and RIT should focus on targeting vegetative cells and germinating spores.

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Nanomechanical Characterization of Bacillus anthracis Spores by Atomic Force Microscopy

Applied and Environmental Microbiology ◽

10.1128/aem.00431-16 ◽

2016 ◽

Vol 82 (10) ◽

pp. 2988-2999 ◽

Cited By ~ 6

Author(s):

Alex G. Li ◽

Larry W. Burggraf ◽

Yun Xing

Keyword(s):

Atomic Force Microscopy ◽

Bacillus Anthracis ◽

Elevated Temperatures ◽

Adhesion Force ◽

Spore Surface ◽

Content Type ◽

Force Microscopy ◽

Nanomechanical Properties ◽

Atomic Force ◽

Bacillus Anthracis Spores

ABSTRACTThe study of structures and properties of bacterial spores is important to understanding spore formation and biological responses to environmental stresses. While significant progress has been made over the years in elucidating the multilayer architecture of spores, the mechanical properties of the spore interior are not known. Here, we present a thermal atomic force microscopy (AFM) study of the nanomechanical properties of internal structures ofBacillus anthracisspores. We developed a nanosurgical sectioning method in which a stiff diamond AFM tip was used to cut an individual spore, exposing its internal structure, and a soft AFM tip was used to image and characterize the spore interior on the nanometer scale. We observed that the elastic modulus and adhesion force, including their thermal responses at elevated temperatures, varied significantly in different regions of the spore section. Our AFM images indicated that the peptidoglycan (PG) cortex ofBacillus anthracisspores consisted of rod-like nanometer-sized structures that are oriented in the direction perpendicular to the spore surface. Our findings may shed light on the spore architecture and properties.IMPORTANCEA nanosurgical AFM method was developed that can be used to probe the structure and properties of the spore interior. The previously unknown ultrastructure of the PG cortex ofBacillus anthracisspores was observed to consist of nanometer-sized rod-like structures that are oriented in the direction perpendicular to the spore surface. The variations in the nanomechanical properties of the spore section were largely correlated with its chemical composition. Different components of the spore materials showed different thermal responses at elevated temperatures.

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Tetrazole-Based trans-Translation Inhibitors Kill Bacillus anthracis Spores To Protect Host Cells

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01199-17 ◽

2017 ◽

Vol 61 (10) ◽

Cited By ~ 4

Author(s):

John N. Alumasa ◽

Tyler D. P. Goralski ◽

Kenneth C. Keiler

Keyword(s):

Bacillus Anthracis ◽

Host Cells ◽

Vegetative Cells ◽

Content Type ◽

Chemical Agents ◽

Germination Process ◽

Bacillus Anthracis Spores ◽

Lethal Doses ◽

Potential Use

ABSTRACT Bacillus anthracis, the causative agent of anthrax, remains a significant threat to humans, including potential use in bioterrorism and biowarfare. The capacity to engineer strains with increased pathogenicity coupled with the ease of disseminating lethal doses of B. anthracis spores makes it necessary to identify chemical agents that target and kill spores. Here, we demonstrate that a tetrazole-based trans-translation inhibitor, KKL-55, is bactericidal against vegetative cells of B. anthracis in culture. Using a fluorescent analog, we show that this class of compounds colocalizes with developing endospores and bind purified spores in vitro. KKL-55 was effective against spores at concentrations close to its MIC for vegetative cells. Spore germination was inhibited at 1.2× MIC, and spores were killed at 2× MIC. In contrast, ciprofloxacin killed germinants at concentrations close to its MIC but did not prevent germination even at 32× MIC. Because toxins are released by germinants, macrophages infected by B. anthracis spores are killed early in the germination process. At ≥2× MIC, KKL-55 protected macrophages from death after infection with B. anthracis spores. Ciprofloxacin required concentrations of ≥8× MIC to exhibit a similar effect. Taken together, these data indicate that KKL-55 and related tetrazoles are good lead candidates for therapeutics targeting B. anthracis spores and suggest that there is an early requirement for trans-translation in germinating spores.

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National Validation Study of a Cellulose Sponge Wipe-Processing Method for Use after Sampling Bacillus anthracis Spores from Surfaces

Applied and Environmental Microbiology ◽

10.1128/aem.05377-11 ◽

2011 ◽

Vol 77 (23) ◽

pp. 8355-8359 ◽

Cited By ~ 46

Author(s):

Laura J. Rose ◽

Lisa Hodges ◽

Heather O'Connell ◽

Judith Noble-Wang

Keyword(s):

Bacillus Anthracis ◽

Validation Study ◽

Processing Method ◽

Environmental Sampling ◽

Content Type ◽

Cellulose Sponge ◽

Response Network ◽

Percent Recovery ◽

Bacillus Anthracis Spores ◽

Sensitivity Specificity

ABSTRACTThis work was initiated to address the gaps identified by Congress regarding validated biothreat environmental sampling and processing methods. Nine Laboratory Response Network-affiliated laboratories participated in a validation study of a cellulose sponge wipe-processing protocol for the recovery, detection, and quantification of viableBacillus anthracisSterne spores from steel surfaces. Steel coupons (645.16 cm2) were inoculated with 1 to 4 log10spores and then sampled with cellulose sponges (Sponge-Stick; 3M, St. Paul, MN). Surrogate dust and background organisms were added to the sponges to mimic environmental conditions. Labs processed the sponges according to the provided protocol. Sensitivity, specificity, and mean percent recovery (%R), between-lab variability, within-lab variability, and total percent coefficient of variation were calculated. The mean %R (standard error) of spores from the surface was 32.4 (4.4), 24.4 (2.8), and 30.1 (2.3) for the 1-, 2-, and 4-log10inoculum levels, respectively. Sensitivities for colony counts were 84.1%, 100%, and 100% for the 1-, 2-, and 4-log10inocula, respectively. These data help to characterize the variability of the processing method and thereby enhance confidence in the interpretation of the results of environmental sampling conducted during aB. anthraciscontamination investigation.

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Dendritic Cells Endocytose Bacillus Anthracis Spores: Implications for Anthrax Pathogenesis

10.21236/ada434591 ◽

2005 ◽

Author(s):

Katherine C. Brittingham ◽

Gordon Ruthel ◽

Rekha G. Panchal ◽

Claudette L. Fuller ◽

Wilson J. Ribot

Keyword(s):

Dendritic Cells ◽

Bacillus Anthracis ◽

Bacillus Anthracis Spores

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PROMETHEE-based ranking of project managers based on the five personality traits

Kybernetes ◽

10.1108/k-10-2018-0551 ◽

2019 ◽

Vol 49 (4) ◽

pp. 1083-1102

Author(s):

Georgios N. Aretoulis ◽

Jason Papathanasiou ◽

Fani Antoniou

Keyword(s):

Personality Traits ◽

Questionnaire Survey ◽

Multicriteria Decision Making ◽

Project Managers ◽

Preference Ranking ◽

Infrastructure Projects ◽

Public Infrastructure ◽

Content Type ◽

The One ◽

Selection Of

Purpose This paper aims to rank and identify the most efficient project managers (PMs) based on personality traits, using Preference Ranking Organization METHod for Enrichment Evaluations (PROMETHEE) methodology. Design/methodology/approach The proposed methodology relies on the five personality traits. These were used as the selection criteria. A questionnaire survey among 82 experienced engineers was used to estimate the required weights per personality trait. A second two-part questionnaire survey aimed at recording the PMs profile and assess the performance of personality traits per PM. PMs with the most years of experience are selected to be ranked through Visual PROMETHEE. Findings The findings suggest that a competent PM is the one that scores low on the “Neuroticism” trait and high especially on the “Conscientiousness” trait. Research limitations/implications The research applied a psychometric test specifically designed for Greek people. Furthermore, the proposed methodology is based on the personality characteristics to rank the PMs and does not consider the technical skills. Furthermore, the type of project is not considered in the process of ranking PMs. Practical implications The findings could contribute in the selection of the best PM that maximizes the project team’s performance. Social implications Improved project team communication and collaboration leading to improved project performance through better communication and collaboration. This is an additional benefit for the society, especially in the delivery of public infrastructure projects. A lot of public infrastructure projects deviate largely as far as cost and schedule is concerned and this is an additional burden for public and society. Proper project management through efficient PMs would save people’s money and time. Originality/value Identification of the best PMbased on a combination of multicriteria decision-making and psychometric tests, which focus on personality traits.

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Investor protection and market reaction to unusual market activity replies

International Journal of Emerging Markets ◽

10.1108/ijoem-10-2019-0859 ◽

2020 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Chun-Teck Lye ◽

Tuan-Hock Ng ◽

Kwee-Pheng Lim ◽

Chin-Yee Gan

Keyword(s):

Market Reaction ◽

Investor Protection ◽

Abnormal Returns ◽

Stock Exchanges ◽

Uncertain Information ◽

Information Uncertainty ◽

Content Type ◽

Market Activity ◽

Information Hypothesis ◽

New Information

PurposeThis study uses the unique setting of unusual market activity (UMA) replies to examine the market reaction and the effects of disclosure and investor protection amid information uncertainty.Design/methodology/approachA total of 1527 hand-collected UMA replies from the interlinked stock exchanges of Indonesia, Malaysia, Thailand and Singapore for the period of 2015–2017 were analysed using event study and Heckman two-step methods with market and matched control firm benchmarks.FindingsThe overall results support the uncertain information hypothesis. The UMA replies with new information were also found to reduce information uncertainty, but not information asymmetry, and they are complementary to investor protection in enhancing abnormal returns. The overall finding suggests that the UMA public query system can be an effective market intervention mechanism in improving information certainty and efficiency.Research limitations/implicationsThis study provides insight on the effects of news replies and investor protection on abnormal returns, and support for the uncertain information hypothesis. The finding is useful to policymakers and stock exchanges as they seek to understand how to alleviate investors' anxiety and to create an informationally efficient market. Nevertheless, this study is limited by the extensiveness of the hand-collected UMA replies and also the potential issue of simultaneity-induced endogeneity.Originality/valueThis study uses UMA replies and cross-country data taking into account the effects of market surroundings such as information uncertainty and the level of investor protection on market reaction.

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