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Yadav U, Abbas Z, Butcher RJ, Patra AK. A luminescent terbium( iii) probe as an efficient ‘Turn-ON’ sensor for dipicolinic acid, a Bacillus Anthracis biomarker. NEW J CHEM 2022. [DOI: 10.1039/d2nj03437a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This work drives the potential of lanthanide luminescence in the quantification and detection of the B. Anthracis bacterial spore by targeting dipicolinic acid (DPA), a principal component of anthrax spores.
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Affiliation(s)
- Usha Yadav
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, Uttar Pradesh, India
| | - Zafar Abbas
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, Uttar Pradesh, India
| | - Ray J. Butcher
- Department of Chemistry, Howard University, Washington, DC 20059, USA
| | - Ashis K. Patra
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, Uttar Pradesh, India
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2
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Saxena M, Nandi S, Saxena AK. QSAR and molecular docking studies of lethal factor protease inhibitors against Bacillus anthracis. SAR AND QSAR IN ENVIRONMENTAL RESEARCH 2019; 30:715-731. [PMID: 31556709 DOI: 10.1080/1062936x.2019.1658219] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Accepted: 08/18/2019] [Indexed: 06/10/2023]
Abstract
Bacillus anthracis is considered as a biological warfare agent because it is the causative agent of the serious infectious anthrax disease. Delay in treatment leads to lethal factor-mediated toxaemia which is very critical due to lack of therapeutic options. Consequently, attempts have been made to discover potent lethal factor (LF) protease inhibitors such as small-molecule synthetic 2-thio-1,3-thiazolidine-4-one (rhodanine) compounds. But computed descriptor-based quantitative structure-activity relationship (QSAR) and drug design studies on such aspect are poorly represented. Therefore, an attempt was made for developing QSAR models using structural descriptors for 1,3-thiazolidine-4-one compounds. The models were developed on a series of 49 LF protease inhibitors using the combination of constitutional, functional group, atom-centred fragment and molecular property descriptors. The best QSAR model included four variables, namely, C-040, nR05, GVWAI-80 and ALOGP that correlated well with the anti-LF protease activity with a good correlation coefficient (r = 0.870) of good statistical significance (F4, 29 = 14.09 (α = 0.001) F4, 29 = 6.19). This model was also validated and explained 58.1% of variances of the Bacillus anthracis inhibitory activities of the studied compounds with r2pred = 0.710 which denotes external predictability. Finally, molecular docking was carried out to predict the mode of binding of some highly active congeneric compounds. It was shown that VAL 1403 is an important residue for phenyl ring. TYR 1456 and HIS 1418 are responsible for interaction with the rhodanine nucleus. Therefore, these residues are considered responsible for the inhibition of LF protease anthrax and can predict significant dimension of essential structural features of these inhibitors to evaluate, screen and help priorities of the synthesis of the candidates against anthrax bioterrorism.
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Affiliation(s)
- M Saxena
- Department of Chemistry, Amity University , Lucknow , India
| | - S Nandi
- Department of Pharmaceutical Chemistry, Global Institute of Pharmaceutical Education and Research, Affiliated to Uttarakhand Technical University , Kashipur , India
| | - A K Saxena
- Division of Medicinal and Process Chemistry, CSIR-Central Drug Research Institute , Lucknow , India
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3
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Omersa N, Podobnik M, Anderluh G. Inhibition of Pore-Forming Proteins. Toxins (Basel) 2019; 11:E545. [PMID: 31546810 PMCID: PMC6784129 DOI: 10.3390/toxins11090545] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 08/27/2019] [Accepted: 09/10/2019] [Indexed: 12/16/2022] Open
Abstract
Perforation of cellular membranes by pore-forming proteins can affect cell physiology, tissue integrity, or immune response. Since many pore-forming proteins are toxins or highly potent virulence factors, they represent an attractive target for the development of molecules that neutralize their actions with high efficacy. There has been an assortment of inhibitors developed to specifically obstruct the activity of pore-forming proteins, in addition to vaccination and antibiotics that serve as a plausible treatment for the majority of diseases caused by bacterial infections. Here we review a wide range of potential inhibitors that can specifically and effectively block the activity of pore-forming proteins, from small molecules to more specific macromolecular systems, such as synthetic nanoparticles, antibodies, antibody mimetics, polyvalent inhibitors, and dominant negative mutants. We discuss their mechanism of inhibition, as well as advantages and disadvantages.
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Affiliation(s)
- Neža Omersa
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia.
| | - Marjetka Podobnik
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia.
| | - Gregor Anderluh
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia.
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Characterisation of the antibacterial properties of the recombinant phage endolysins AP50-31 and LysB4 as potent bactericidal agents against Bacillus anthracis. Sci Rep 2018; 8:18. [PMID: 29311588 PMCID: PMC5758571 DOI: 10.1038/s41598-017-18535-z] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Accepted: 12/08/2017] [Indexed: 11/08/2022] Open
Abstract
The recombinant phage endolysins AP50-31 and LysB4 were developed using genetic information from bacteriophages AP50 and B4 and were produced by microbial cultivation followed by chromatographic purification. Subsequently, appropriate formulations were developed that provided an acceptable stability of the recombinant endolysins. The bacteriolytic properties of the formulated endolysins AP50-31 and LysB4 against several bacterial strains belonging to the Bacillus genus including Bacillus anthracis (anthrax) strains were examined. AP50-31 and LysB4 displayed rapid bacteriolytic activity and broad bacteriolytic spectra within the Bacillus genus, including bacteriolytic activity against all the B. anthracis strains tested. When administered intranasally, LysB4 completely protected A/J mice from lethality after infection with the spores of B. anthracis Sterne. When examined at 3 days post-infection, bacterial counts in the major organs (lung, liver, kidney, and spleen) were significantly lower compared with those of the control group that was not treated with endolysin. In addition, histopathological examinations revealed a marked improvement of pathological features in the LysB4-treated group. The results of this study support the idea that phage endolysins are promising candidates for developing therapeutics against anthrax infection.
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Kielmann M, Prior C, Senge MO. Porphyrins in troubled times: a spotlight on porphyrins and their metal complexes for explosives testing and CBRN defense. NEW J CHEM 2018. [DOI: 10.1039/c7nj04679k] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A critical perspective on (metallo)porphyrins in security-related applications: the past, present and future of explosives detection, CBRN defense, and beyond.
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Affiliation(s)
- Marc Kielmann
- School of Chemistry
- SFI Tetrapyrrole Laboratory
- Trinity Biomedical Sciences Institute
- Trinity College Dublin
- The University of Dublin
| | - Caroline Prior
- School of Chemistry
- SFI Tetrapyrrole Laboratory
- Trinity Biomedical Sciences Institute
- Trinity College Dublin
- The University of Dublin
| | - Mathias O. Senge
- Medicinal Chemistry
- Trinity Translational Medicine Institute
- Trinity Centre for Health Sciences
- Trinity College Dublin
- The University of Dublin
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Yuan HL, Zheng YY, Zhang W, Xie H. Two cases of human cutaneous anthrax with massive tissue damage, severe edema, and slight injury to the liver. Int J Dermatol 2017; 57:358-361. [PMID: 29231245 DOI: 10.1111/ijd.13865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2017] [Revised: 09/07/2017] [Accepted: 11/12/2017] [Indexed: 11/30/2022]
Affiliation(s)
- Hai-Ling Yuan
- Department of Pharmacy, Anning Branch Lanzhou General Hospital Lanzhou Command, Lanzhou, China
| | - Yuan-Yuan Zheng
- Department of Pharmacy, Anning Branch Lanzhou General Hospital Lanzhou Command, Lanzhou, China
| | - Wen Zhang
- Department of Pharmacy, Anning Branch Lanzhou General Hospital Lanzhou Command, Lanzhou, China
| | - Hua Xie
- Department of Pharmacy, Anning Branch Lanzhou General Hospital Lanzhou Command, Lanzhou, China
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Tetrazole-Based trans-Translation Inhibitors Kill Bacillus anthracis Spores To Protect Host Cells. Antimicrob Agents Chemother 2017; 61:AAC.01199-17. [PMID: 28760903 DOI: 10.1128/aac.01199-17] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 07/21/2017] [Indexed: 12/29/2022] Open
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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Guo J, Wang A, Yang K, Ding H, Hu Y, Yang Y, Huang S, Xu J, Liu T, Yang H, Xin Z. Isolation, characterization and antimicrobial activities of polyacetylene glycosides from Coreopsis tinctoria Nutt. PHYTOCHEMISTRY 2017; 136:65-69. [PMID: 28104231 DOI: 10.1016/j.phytochem.2016.12.023] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2016] [Revised: 12/16/2016] [Accepted: 12/29/2016] [Indexed: 06/06/2023]
Abstract
Polyacetylene glycosides, (6Z, 12E)-tetradecadiene-8,10-diyne-1-ol-3(R)-O-β-D-glucopyranoside (trivially named coreoside E) and (6Z, 12E)-tetradecadiene-8,10-diyne-1-ol-3(R)-O-β-L-arabinopyranosyl-(1 → 2)-β-D-glucopyranoside (trivially named coreoside F), were isolated from buds of Coreopsis tinctoria Nutt., together with one known compound, coreoside B. Their chemical structures were elucidated by extensive spectroscopic analysis and on the basis of their chemical reactivities. Coreoside E exhibited high levels of antimicrobial activity against Staphylococcus aureus and Bacillus anthracis with minimum inhibitory concentrations of 27 ± 0.27 and 18 ± 0.40 μM, respectively, whereas coreoside F and coreoside B showed weak antimicrobial activity against S. aureus and B. anthracis.
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Affiliation(s)
- Jia Guo
- Key Laboratory of Food Processing and Quality Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Ao Wang
- Key Laboratory of Food Processing and Quality Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Ke Yang
- Key Laboratory of Food Processing and Quality Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Hao Ding
- Key Laboratory of Food Processing and Quality Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China; College of Food Science and Pharmacy, Xinjiang Agricultural University, Urumqi, People's Republic of China
| | - Yimin Hu
- Key Laboratory of Food Processing and Quality Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Yumeng Yang
- Key Laboratory of Food Processing and Quality Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Siqi Huang
- Key Laboratory of Food Processing and Quality Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Jingguo Xu
- Key Laboratory of Food Processing and Quality Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Tianxing Liu
- Key Laboratory of Food Processing and Quality Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Haiyan Yang
- College of Food Science and Pharmacy, Xinjiang Agricultural University, Urumqi, People's Republic of China
| | - Zhihong Xin
- Key Laboratory of Food Processing and Quality Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China.
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Adenine and benzimidazole-based mimics of REP-3123 as antibacterial agents against Clostridium difficile and Bacillus anthracis: Design, synthesis and biological evaluation. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.bfopcu.2016.06.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Ohanjanian L, Remy KE, Li Y, Cui X, Eichacker PQ. An overview of investigational toxin-directed therapies for the adjunctive management of Bacillus anthracis infection and sepsis. Expert Opin Investig Drugs 2015; 24:851-65. [PMID: 25920540 DOI: 10.1517/13543784.2015.1041587] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
INTRODUCTION Sepsis with Bacillus anthracis infection has a very high mortality rate despite appropriate antibiotic and supportive therapies. Over the past 15 years, recent outbreaks in the US and in Europe, coupled with anthrax's bioterrorism weapon potential, have stimulated efforts to develop adjunctive therapies to improve clinical outcomes. Since lethal toxin and edema toxin (LT and ET) make central contributions to the pathogenesis of B. anthracis, these have been major targets in this effort. AREAS COVERED Here, the authors review different investigative biopharmaceuticals that have been recently identified for their therapeutic potential as inhibitors of LT or ET. Among these inhibitors are two antibody preparations that have been included in the Strategic National Stockpile (SNS) and several more that have reached Phase I testing. Presently, however, many of these candidate agents have only been studied in vitro and very few tested in bacteria-challenged models. EXPERT OPINION Although a large number of drugs have been identified as potential therapeutic inhibitors of LT and ET, in most cases their testing has been limited. The use of the two SNS antibody therapies during a large-scale exposure to B. anthracis will be difficult. Further testing and development of agents with oral bioavailability and relatively long shelf lives should be a focus for future research.
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Affiliation(s)
- Lernik Ohanjanian
- National Institutes of Health, Clinical Center, Critical Care Medicine Department , Building 10, Room 2C145, Bethesda, MD 20892 , USA +1 301 402 2914 ; +1 301 402 1213 ;
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Production and cell surface display of recombinant anthrax protective antigen on the surface layer of attenuated Bacillus anthracis. World J Microbiol Biotechnol 2014; 31:345-52. [PMID: 25504373 DOI: 10.1007/s11274-014-1786-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2014] [Accepted: 12/05/2014] [Indexed: 10/24/2022]
Abstract
To investigate the surface display of the anthrax protective antigen (PA) on attenuated Bacillus anthracis, a recombinant B. anthracis strain, named AP429 was constructed by integrating into the chromosome a translational fusion harboring the DNA fragments encoding the cell wall-targeting domain of the S-layer protein EA1 and the anthrax PA. Crerecombinase action at the loxP sites excised the antibiotic marker. Western blot analysis, fluorescence-activated cell sorting and immunofluorescence analysis confirmed that PA was successfully expressed on the S-layer of the recombinant antibiotic marker-free strain. Notwithstanding extensive proteolytic degradation of the hybrid protein SLHs-PA, quantitative ELISA revealed that approximately 8.1 × 10(6) molecules of SLHs-PA were gained from each Bacillus cell. Moreover, electron microscopy assay indicated that the typical S-layer structures could be clearly observed from the recombinant strain micrographs.
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Adamo R. Glycan surface antigens fromBacillus anthracisas vaccine targets: current status and future perspectives. Expert Rev Vaccines 2014; 13:895-907. [DOI: 10.1586/14760584.2014.924404] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Kaur M, Singh S, Bhatnagar R. Anthrax vaccines: present status and future prospects. Expert Rev Vaccines 2014; 12:955-70. [PMID: 23984963 DOI: 10.1586/14760584.2013.814860] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The management of anthrax remains a top priority among the biowarfare/bioterror agents. It was the Bacillus anthracis spore attack through the US mail system after the September 11, 2001, terrorist attacks in the USA that highlighted the potential of B. anthracis as a bioterrorism agent and the threat posed by its deliberate dissemination. These attacks invigorated the efforts toward understanding the anthrax pathogenesis and development of more comprehensive medical intervention strategies for its containment in case of both natural disease and manmade, accidental or deliberate infection of a non-suspecting population. Currently, efforts are directed toward the development of safe and efficacious vaccines as well as intervention tools for controlling the disease in the advanced fulminant stage when toxemia has already developed. This work presents an overview of the current understanding of anthrax pathogenesis and recent advances made, particularly after 2001, for the successful management of anthrax and outlines future perspectives.
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Affiliation(s)
- Manpreet Kaur
- Laboratory of Molecular Biology and Genetic Engineering, School of Biotechnology, Jawaharlal Nehru University, New Delhi 110067, Delhi, India
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Abstract
INTRODUCTION Present-day rational drug design approaches are based on exploiting unique features of the target biomolecules, small- or macromolecule drug candidates and physical forces that govern their interactions. The 2013 Nobel Prize in chemistry awarded 'for the development of multiscale models for complex chemical systems' once again demonstrated the importance of the tailored drug discovery that reduces the role of the trial-and-error approach to a minimum. The intentional dissemination of Bacillus anthracis spores in 2001 via the so-called anthrax letters has led to increased efforts, politically and scientifically, to develop medical countermeasures that will protect people from the threat of anthrax bioterrorism. AREAS COVERED This article provides an overview of the recent rational drug design approaches for discovering inhibitors of anthrax toxin. The review also directs the readers to the vast literature on the recognized advances and future possibilities in the field. EXPERT OPINION Existing options to combat anthrax toxin lethality are limited. With the only anthrax toxin inhibiting therapy (protective antigen-targeting with a monoclonal antibody, raxibacumab) approved to treat inhalational anthrax, the situation, in our view, is still insecure. Further, the FDA's animal rule for drug approval, which clears compounds without validated efficacy studies on humans, creates a high level of uncertainty, especially when a well-characterized animal model does not exist. Better identification and validation of anthrax toxin therapeutic targets at the molecular level as well as elucidation of the parameters determining the corresponding therapeutic windows are still necessary for more effective therapeutic options.
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Affiliation(s)
- Ekaterina M Nestorovich
- The Catholic University of America, Department of Biology , Washington, DC , USA +1 202 319 6723 ;
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Kim DJ, Park HC, Sohn IY, Jung JH, Yoon OJ, Park JS, Yoon MY, Lee NE. Electrical graphene aptasensor for ultra-sensitive detection of anthrax toxin with amplified signal transduction. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2013; 9:3352-3360. [PMID: 23589198 DOI: 10.1002/smll.201203245] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2012] [Revised: 01/23/2013] [Indexed: 06/02/2023]
Abstract
Detection of the anthrax toxin, the protective antigen (PA), at the attomolar (aM) level is demonstrated by an electrical aptamer sensor based on a chemically derived graphene field-effect transistor (FET) platform. Higher affinity of the aptamer probes to PA in the aptamer-immobilized FET enables significant improvements in the limit of detection (LOD), dynamic range, and sensitivity compared to the antibody-immobilized FET. Transduction signal enhancement in the aptamer FET due to an increase in captured PA molecules results in a larger 30 mV/decade shift in the charge neutrality point (Vg,min ) as a sensitivity parameter, with the dynamic range of the PA concentration between 12 aM (LOD) and 120 fM. An additional signal enhancement is obtained by the secondary aptamer-conjugated gold nanoparticles (AuNPs-aptamer), which have a sandwich structure of aptamer/PA/aptamer-AuNPs, induce an increase in charge-doping in the graphene channel, resulting in a reduction of the LOD to 1.2 aM with a three-fold increase in the Vg,min shift.
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Affiliation(s)
- Duck-Jin Kim
- Department of Chemistry, Hanyang University, Seoul 133-791, Korea
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Russell L, Pedersen M, Jensen AV, Søes LM, Hansen ABE. Two anthrax cases with soft tissue infection, severe oedema and sepsis in Danish heroin users. BMC Infect Dis 2013; 13:408. [PMID: 24004900 PMCID: PMC3844346 DOI: 10.1186/1471-2334-13-408] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Accepted: 08/27/2013] [Indexed: 01/21/2023] Open
Abstract
Background Anthrax had become extremely rare in Europe, but in 2010 an outbreak of anthrax among heroin users in Scotland increased awareness of contaminated heroin as a source of anthrax. We present the first two Danish cases of injectional anthrax and discuss the clinical presentations, which included both typical and more unusual manifestations. Case presentations The first patient, a 55-year old man with HIV and hepatitis C virus co-infection, presented with severe pain in the right thigh and lower abdomen after injecting heroin into the right groin. Computed tomography and ultrasonographic examination of the abdomen and right thigh showed oedematous thickened peritoneum, distended oedematous mesentery and subcutaneous oedema of the right thigh. At admission the patient was afebrile but within 24 hours he progressed to severe septic shock and abdominal compartment syndrome. Cultures of blood and intraperitoneal fluid grew Bacillus anthracis. The patient was treated with meropenem, clindamycin, ciprofloxacin and metronidazole. Despite maximum supportive care including mechanical ventilation, vasopressor treatment and continuous veno-venous hemodiafiltration the patient died on day four. The second patient, a 39-year old man with chronic hepatitis C virus infection, presented with fever and a swollen right arm after injecting heroin into his right arm. The arm was swollen from the axilla to the wrist with tense and discoloured skin. He was initially septic with low blood pressure but responded to crystalloids. During the first week, swelling progressed and the patient developed massive generalised oedema with a weight gain of 40 kg. When blood cultures grew Bacillus anthracis antibiotic treatment was changed to meropenem, moxifloxacin and metronidazole, and on day 7 hydroxycloroquin was added. The patient responded to treatment and was discharged after 29 days. Conclusions These two heroin-associated anthrax cases from Denmark corroborate that heroin contaminated with anthrax spores may be a continuous source of injectional anthrax across Europe. Clinicians and clinical microbiologists need to stay vigilant and suspect anthrax in patients with a history of heroin use who present with soft tissue or generalised infection. Marked swelling of affected soft tissue or unusual intra-abdominal oedema should strengthen clinical suspicion.
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Affiliation(s)
- Lene Russell
- Department of Intensive Care 4131, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark.
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Endom EE. Bioterrorism and the Pediatric Patient: An Update. CLINICAL PEDIATRIC EMERGENCY MEDICINE 2013. [DOI: 10.1016/j.cpem.2013.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Wang HYL, Guo H, O'Doherty GA. De novo asymmetric synthesis of oligo-rhamno di- and tri-saccharides related to the anthrax tetrasaccharide. Tetrahedron 2013; 69:3432-3436. [PMID: 23794755 DOI: 10.1016/j.tet.2013.02.073] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
An asymmetric synthesis of the di- and trisaccharide portion of the naturally occurring anthrax tetrasaccharide from acetylfuran has been developed. The construction of the di- and trisaccharide subunits is based upon our previously disclosed route to anthrax tetrasaccharide. The approach uses iterative diastereoselective palladium-catalyzed glycosylations, Luche reductions, diastereoselective dihydroxylations, and regioselective protections for the assembly of the rhamno- di- and tri-saccharide. The route was also modified for the preparation of the mixed D-/L-disaccharide analogue.
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Affiliation(s)
- Hua-Yu Leo Wang
- College of Nuclear Technology, Chemistry and Biology, Hubei University of Science and Technology, Xianning, Hubei 437100, China ; Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Avenue, Boston, MA 02115, USA
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Affiliation(s)
| | - Sergey M. Bezrukov
- Program in Physical Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, U.S.A
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Milhomme O, Köhler SM, Ropartz D, Lesur D, Pilard S, Djedaïni-Pilard F, Beyer W, Grandjean C. Synthesis and immunochemical evaluation of a non-methylated disaccharide analogue of the anthrax tetrasaccharide. Org Biomol Chem 2012; 10:8524-32. [PMID: 23010801 DOI: 10.1039/c2ob26131f] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Anthrax tetrasaccharide is an oligosaccharide expressed at the outermost surface of the Bacillus anthracis spores, featuring three rhamnoses and a rare sugar called anthrose. This motif has now been identified as a plausible component of future human vaccines against anthrax. We report herein the synthesis of a 2-O-demethylated-β-D-anthropyranosyl-(1→3)-α-L-rhamnopyranose disaccharide analogue of this tetrasaccharide from a cyclic sulfate intermediate. This disaccharide conjugated to BSA induces an anti-native tetrasaccharide IgG antibody response when administered in BALB/c mice. Moreover, induced sera bound to native B. anthracis endospores. These results suggest that the disaccharide analogue, easily amenable for a synthetic scale-up, could be used in a glycoconjugate antigen formulation.
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Affiliation(s)
- Ophélie Milhomme
- Laboratoire des Glucides, FRE CNRS 3517, Institut de Chimie de Picardie, Université de Picardie Jules Verne, 33 rue Saint Leu, 80039 Amiens Cedex, France
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A three-dose intramuscular injection schedule of anthrax vaccine adsorbed generates sustained humoral and cellular immune responses to protective antigen and provides long-term protection against inhalation anthrax in rhesus macaques. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2012; 19:1730-45. [PMID: 22933399 DOI: 10.1128/cvi.00324-12] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A 3-dose (0, 1, and 6 months) intramuscular (3-IM) priming series of a human dose (HuAVA) and dilutions of up to 1:10 of anthrax vaccine adsorbed (AVA) provided statistically significant levels of protection (60 to 100%) against inhalation anthrax for up to 4 years in rhesus macaques. Serum anti-protective antigen (anti-PA) IgG and lethal toxin neutralization activity (TNA) were detectable following a single injection of HuAVA or 1:5 AVA or following two injections of diluted vaccine (1:10, 1:20, or 1:40 AVA). Anti-PA and TNA were highly correlated (overall r(2) = 0.89 for log(10)-transformed data). Peak responses were seen at 6.5 months. In general, with the exception of animals receiving 1:40 AVA, serum anti-PA and TNA responses remained significantly above control levels at 28.5 months (the last time point measured for 1:20 AVA), and through 50.5 months for the HuAVA and 1:5 and 1:10 AVA groups (P < 0.05). PA-specific gamma interferon (IFN-γ) and interleukin-4 (IL-4) CD4(+) cell frequencies and T cell stimulation indices were sustained through 50.5 months (the last time point measured). PA-specific memory B cell frequencies were highly variable but, in general, were detectable in peripheral blood mononuclear cells (PBMC) by 2 months, were significantly above control levels by 7 months, and remained detectable in the HuAVA and 1:5 and 1:20 AVA groups through 42 months (the last time point measured). HuAVA and diluted AVA elicited a combined Th1/Th2 response and robust immunological priming, with sustained production of high-avidity PA-specific functional antibody, long-term immune cell competence, and immunological memory (30 months for 1:20 AVA and 52 months for 1:10 AVA). Vaccinated animals surviving inhalation anthrax developed high-magnitude anamnestic anti-PA IgG and TNA responses.
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Milhomme O, Dhénin SG, Djedaïni-Pilard F, Moreau V, Grandjean C. Synthetic studies toward the anthrax tetrasaccharide: alternative synthesis of this antigen. Carbohydr Res 2012; 356:115-31. [DOI: 10.1016/j.carres.2012.01.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Revised: 01/15/2012] [Accepted: 01/17/2012] [Indexed: 10/14/2022]
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Development of anti-infectives using phage display: biological agents against bacteria, viruses, and parasites. Antimicrob Agents Chemother 2012; 56:4569-82. [PMID: 22664969 DOI: 10.1128/aac.00567-12] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The vast majority of anti-infective therapeutics on the market or in development are small molecules; however, there is now a nascent pipeline of biological agents in development. Until recently, phage display technologies were used mainly to produce monoclonal antibodies (MAbs) targeted against cancer or inflammatory disease targets. Patent disputes impeded broad use of these methods and contributed to the dearth of candidates in the clinic during the 1990s. Today, however, phage display is recognized as a powerful tool for selecting novel peptides and antibodies that can bind to a wide range of antigens, ranging from whole cells to proteins and lipid targets. In this review, we highlight research that exploits phage display technology as a means of discovering novel therapeutics against infectious diseases, with a focus on antimicrobial peptides and antibodies in clinical or preclinical development. We discuss the different strategies and methods used to derive, select, and develop anti-infectives from phage display libraries and then highlight case studies of drug candidates in the process of development and commercialization. Advances in screening, manufacturing, and humanization technologies now mean that phage display can make a significant contribution in the fight against clinically important pathogens.
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Hou J, Wojciechowska K, Zheng H, Chruszcz M, Cooper DR, Cymborowski M, Skarina T, Gordon E, Luo H, Savchenko A, Minor W. Structure of a short-chain dehydrogenase/reductase from Bacillus anthracis. Acta Crystallogr Sect F Struct Biol Cryst Commun 2012; 68:632-7. [PMID: 22684058 PMCID: PMC3370898 DOI: 10.1107/s1744309112017939] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Accepted: 04/22/2012] [Indexed: 11/10/2022]
Abstract
The crystal structure of a short-chain dehydrogenase/reductase from Bacillus anthracis strain `Ames Ancestor' complexed with NADP has been determined and refined to 1.87 Å resolution. The structure of the enzyme consists of a Rossmann fold composed of seven parallel β-strands sandwiched by three α-helices on each side. An NADP molecule from an endogenous source is bound in the conserved binding pocket in the syn conformation. The loop region responsible for binding another substrate forms two perpendicular short helices connected by a sharp turn.
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Affiliation(s)
- Jing Hou
- Molecular Physiology and Biological Physics, University of Virginia, 1340 Jefferson Park Avenue, Jordan Hall, Room 4223, Charlottesville, VA 22908, USA
- Center for Structural Genomics of Infectious Diseases (CSGID), USA
| | - Kamila Wojciechowska
- Molecular Physiology and Biological Physics, University of Virginia, 1340 Jefferson Park Avenue, Jordan Hall, Room 4223, Charlottesville, VA 22908, USA
| | - Heping Zheng
- Molecular Physiology and Biological Physics, University of Virginia, 1340 Jefferson Park Avenue, Jordan Hall, Room 4223, Charlottesville, VA 22908, USA
- Center for Structural Genomics of Infectious Diseases (CSGID), USA
| | - Maksymilian Chruszcz
- Molecular Physiology and Biological Physics, University of Virginia, 1340 Jefferson Park Avenue, Jordan Hall, Room 4223, Charlottesville, VA 22908, USA
- Center for Structural Genomics of Infectious Diseases (CSGID), USA
| | - David R. Cooper
- Molecular Physiology and Biological Physics, University of Virginia, 1340 Jefferson Park Avenue, Jordan Hall, Room 4223, Charlottesville, VA 22908, USA
- Center for Structural Genomics of Infectious Diseases (CSGID), USA
| | - Marcin Cymborowski
- Molecular Physiology and Biological Physics, University of Virginia, 1340 Jefferson Park Avenue, Jordan Hall, Room 4223, Charlottesville, VA 22908, USA
- Center for Structural Genomics of Infectious Diseases (CSGID), USA
| | - Tatiana Skarina
- Center for Structural Genomics of Infectious Diseases (CSGID), USA
- Banting and Best Department of Medical Research, University of Toronto, 112 College Street, Toronto, Ontario, Canada
| | - Elena Gordon
- Center for Structural Genomics of Infectious Diseases (CSGID), USA
- Banting and Best Department of Medical Research, University of Toronto, 112 College Street, Toronto, Ontario, Canada
| | - Haibin Luo
- Molecular Physiology and Biological Physics, University of Virginia, 1340 Jefferson Park Avenue, Jordan Hall, Room 4223, Charlottesville, VA 22908, USA
- Center for Structural Genomics of Infectious Diseases (CSGID), USA
| | - Alexei Savchenko
- Center for Structural Genomics of Infectious Diseases (CSGID), USA
- Banting and Best Department of Medical Research, University of Toronto, 112 College Street, Toronto, Ontario, Canada
| | - Wladek Minor
- Molecular Physiology and Biological Physics, University of Virginia, 1340 Jefferson Park Avenue, Jordan Hall, Room 4223, Charlottesville, VA 22908, USA
- Center for Structural Genomics of Infectious Diseases (CSGID), USA
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Beierlein JM, Anderson AC. New developments in vaccines, inhibitors of anthrax toxins, and antibiotic therapeutics for Bacillus anthracis. Curr Med Chem 2012; 18:5083-94. [PMID: 22050756 DOI: 10.2174/092986711797636036] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2011] [Revised: 09/07/2011] [Accepted: 09/09/2011] [Indexed: 01/28/2023]
Abstract
Bacillus anthracis, the causative agent responsible for anthrax infections, poses a significant biodefense threat. There is a high mortality rate associated with untreated anthrax infections; specifically, inhalation anthrax is a particularly virulent form of infection with mortality rates close to 100%, even with aggressive treatment. Currently, a vaccine is not available to the general public and few antibiotics have been approved by the FDA for the treatment of inhalation anthrax. With the threat of natural or engineered bacterial resistance to antibiotics and the limited population for whom the current drugs are approved, there is a clear need for more effective treatments against this deadly infection. A comprehensive review of current research in drug discovery is presented in this article, including efforts to improve the purity and stability of vaccines, design inhibitors targeting the anthrax toxins, and identify inhibitors of novel enzyme targets. High resolution structural information for the anthrax toxins and several essential metabolic enzymes has played a significant role in aiding the structure-based design of potent and selective antibiotics.
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Affiliation(s)
- J M Beierlein
- Dept. Pharmaceutical Sciences, University of Connecticut, 69 N. Eagleville Rd., Storrs, CT 06269, USA
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Hicks CW, Sweeney DA, Cui X, Li Y, Eichacker PQ. An overview of anthrax infection including the recently identified form of disease in injection drug users. Intensive Care Med 2012; 38:1092-104. [PMID: 22527064 DOI: 10.1007/s00134-012-2541-0] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Accepted: 02/14/2012] [Indexed: 02/06/2023]
Abstract
PURPOSE Bacillus anthracis infection (anthrax) can be highly lethal. Two recent outbreaks related to contaminated mail in the USA and heroin in the UK and Europe and its potential as a bioterrorist weapon have greatly increased concerns over anthrax in the developed world. METHODS This review summarizes the microbiology, pathogenesis, diagnosis, and management of anthrax. RESULTS AND CONCLUSIONS Anthrax, a gram-positive bacterium, has typically been associated with three forms of infection: cutaneous, gastrointestinal, and inhalational. However, the anthrax outbreak among injection drug users has emphasized the importance of what is now considered a fourth disease form (i.e., injectional anthrax) that is characterized by severe soft tissue infection. While cutaneous anthrax is most common, its early stages are distinct and prompt appropriate treatment commonly produces a good outcome. However, early symptoms with the other three disease forms can be nonspecific and mistaken for less lethal conditions. As a result, patients with gastrointestinal, inhalational, or injectional anthrax may have advanced infection at presentation that can be highly lethal. Once anthrax is suspected, the diagnosis can usually be made with gram stain and culture from blood or tissue followed by confirmatory testing (e.g., PCR). While antibiotics are the mainstay of anthrax treatment, use of adjunctive therapies such as anthrax toxin antagonists are a consideration. Prompt surgical therapy appears to be important for successful management of injectional anthrax.
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Affiliation(s)
- Caitlin W Hicks
- Cleveland Clinic Lerner College of Medicine, Cleveland, OH 44122, USA
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Mansur HS, Piscitelli Mansur AA. Fluorescent nanohybrids: quantum dots coupled to polymer recombinant protein conjugates for the recognition of biological hazards. ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c2jm31168b] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Zhang B, Dallo S, Peterson R, Hussain S, Weitao T, Ye JY. Detection of anthrax lef with DNA-based photonic crystal sensors. JOURNAL OF BIOMEDICAL OPTICS 2011; 16:127006. [PMID: 22191936 DOI: 10.1117/1.3662460] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Bacillus anthracis has posed a threat of becoming biological weapons of mass destruction due to its virulence factors encoded by the plasmid-borne genes, such as lef for lethal factor. We report the development of a fast and sensitive anthrax DNA biosensor based on a photonic crystal structure used in a total-internal-reflection configuration. For the detection of the lef gene, a single-stranded DNA lef probe was biotinylated and immobilized onto the sensor via biotin-streptavidin interactions. A positive control, lef-com, was the complementary strand of the probe, while a negative control was an unrelated single-stranded DNA fragment from the 16S rRNA gene of Acinetobacter baumannii. After addition of the biotinylated lef probe onto the sensor, significant changes in the resonance wavelength of the sensor were observed, resulting from binding of the probe to streptavidin on the sensor. The addition of lef-com led to another significant increase as a result of hybridization between the two DNA strands. The detection sensitivity for the target DNA reached as low as 0.1 nM. In contrast, adding the unrelated DNAs did not cause an obvious shift in the resonant wavelength. These results demonstrate that detection of the anthrax lef by the photonic crystal structure in a total-internal-reflection sensor is highly specific and sensitive.
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Affiliation(s)
- Bailin Zhang
- University of Texas at San Antonio, Department of Biomedical Engineering, San Antonio, Texas 78249, USA
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Jansa P, Kolman V, Kostinová A, Dračínský M, Mertlíková-Kaiserová H, Janeba Z. Efficient synthesis and biological properties of the 2′-trifluoromethyl analogues of acyclic nucleosides and acyclic nucleoside phosphonates. ACTA ACUST UNITED AC 2011. [DOI: 10.1135/cccc2011105] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Efficient and optimized procedure for the preparation of several acyclic nucleosides and acyclic nucleoside phosphonates substituted at the C-2′ position of the aliphatic part by the trifluoromethyl group is described. Trifluoromethyloxirane was found to be an excellent reagent for the introduction of the 1,1,1-trifluoropropan-2-ol moiety. Surprisingly, the next reaction of these 1,1,1-trifluoropropan-2-ols with the reagent for the introduction of the methylphosphonic residue afforded the desired phosphonates in very high yields and finally a novel simple and scalable procedure for the isolation of free phosphonic acids, after the reaction of dialkyl phosphonates with bromotrimethylsilane, was developed. Prepared compounds were evaluated for their biological properties, but none of the prepared phosphonic acids or acyclic nucleosides exhibits any antiviral, antiproliferative or anti-toxin activities.
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Maffeo D, Velkov Z, Misiakos K, Mergia K, Paulidou A, Zavali M, Mavridis IM, Yannakopoulou K. Real-time monitoring of nanomolar binding to a cyclodextrin monolayer immobilized on a Si/SiO2/novolac surface using white light reflectance spectroscopy: The case of triclosan. J Colloid Interface Sci 2011; 358:369-75. [DOI: 10.1016/j.jcis.2011.03.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Revised: 03/08/2011] [Accepted: 03/08/2011] [Indexed: 10/18/2022]
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Díaz-Moscoso A, Méndez-Ardoy A, Ortega-Caballero F, Benito JM, Ortiz Mellet C, Defaye J, Robinson TM, Yohannes A, Karginov VA, García Fernández JM. Symmetry Complementarity-Guided Design of Anthrax Toxin Inhibitors Based on β-Cyclodextrin: Synthesis and Relative Activities of Face-Selective Functionalized Polycationic Clusters. ChemMedChem 2010; 6:181-92. [DOI: 10.1002/cmdc.201000419] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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A chimeric protein that functions as both an anthrax dual-target antitoxin and a trivalent vaccine. Antimicrob Agents Chemother 2010; 54:4750-7. [PMID: 20713663 DOI: 10.1128/aac.00640-10] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Effective measures for the prophylaxis and treatment of anthrax are still required for counteracting the threat posed by inhalation anthrax. In this study, we first demonstrated that the chimeric protein LFn-PA, created by fusing the protective antigen (PA)-binding domain of lethal factor (LFn) to PA, retained the functions of the respective molecules. On the basis of this observation, we attempted to develop an antitoxin that targets the binding of lethal factor (LF) and/or edema factor (EF) to PA and the transportation of LF/EF. Therefore, we replaced PA in LFn-PA with a dominant-negative inhibitory PA (DPA), i.e., PA(F427D). In in vitro models of anthrax intoxication, the LFn-DPA chimera showed 3-fold and 2-fold higher potencies than DPA in protecting sensitive cells against anthrax lethal toxin (LeTx) and edema toxin (EdTx), respectively. In animal models, LFn-DPA exhibited strong potency in rescuing mice from lethal challenge with LeTx. We also evaluated the immunogenicity and immunoprotective efficacy of LFn-DPA as an anthrax vaccine candidate. In comparison with recombinant PA, LFn-DPA induced significantly higher levels of the anti-PA immune response. Moreover, LFn-DPA elicited an anti-LF antibody response that could cross-react with EF. Mice immunized with LFn-DPA tolerated a LeTx challenge that was 5 times its 50% lethal dose. Thus, LFn-DPA represents a highly effective trivalent vaccine candidate for both preexposure and postexposure vaccination. Overall, we have developed a novel and dually functional reagent for the prophylaxis and treatment of anthrax.
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