1
|
Hoyt KM, Barr JR, Hopkins AO, Dykes JK, Lúquez C, Kalb SR. Validation of a clinical assay for botulinum neurotoxins through mass spectrometric detection. J Clin Microbiol 2024:e0162923. [PMID: 38687021 DOI: 10.1128/jcm.01629-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Accepted: 04/02/2024] [Indexed: 05/02/2024] Open
Abstract
Botulism is a paralytic disease due to the inhibition of acetylcholine exocytosis at the neuromuscular junction, which can be lethal if left untreated. Botulinum neurotoxins (BoNTs) are produced by some spore-forming Clostridium bacteria. The current confirmatory assay to test for BoNTs in clinical specimens is the gold-standard mouse bioassay. However, an Endopep-MS assay method has been developed to detect BoNTs in clinical samples using benchtop mass spectrometric detection. This work demonstrates the validation of the Endopep-MS method for clinical specimens with the intent of method distribution in public health laboratories. The Endopep-MS assay was validated by assessing the sensitivity, robustness, selectivity, specificity, and reproducibility. The limit of detection was found to be equivalent to or more sensitive than the mouse bioassay. Specificity studies determined no cross-reactivity between the different serotypes and no false positives from an exclusivity panel of culture supernatants of enteric disease organisms and non-toxigenic strains of Clostridium. Inter-serotype specificity testing with 19 BoNT subtypes was 100% concordant with the expected results, accurately determining the presence of the correct serotype and the absence of incorrect serotypes. Additionally, a panel of potential interfering substances was used to test selectivity. Finally, clinical studies included clinical specimen stability and reproducibility, which was found to be 99.9% from a multicenter evaluation study. The multicenter validation study also included a clinical validation study, which yielded a 99.4% correct determination rate. Use of the Endopep-MS method will improve the capacity and response time for laboratory confirmation of botulism in public health laboratories.
Collapse
Affiliation(s)
- Kaitlin M Hoyt
- Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - John R Barr
- Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - André O Hopkins
- Division of Foodborne, Waterborne, and Environmental Diseases, National Center for Emerging Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Janet K Dykes
- Division of Foodborne, Waterborne, and Environmental Diseases, National Center for Emerging Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Carolina Lúquez
- Division of Foodborne, Waterborne, and Environmental Diseases, National Center for Emerging Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Suzanne R Kalb
- Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| |
Collapse
|
2
|
Šoštarić P, Matić M, Nemanić D, Lučev Vasić Ž, Cifrek M, Pirazzini M, Matak I. Beyond neuromuscular activity: botulinum toxin type A exerts direct central action on spinal control of movement. Eur J Pharmacol 2024; 962:176242. [PMID: 38048980 DOI: 10.1016/j.ejphar.2023.176242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 11/15/2023] [Accepted: 11/28/2023] [Indexed: 12/06/2023]
Abstract
Overt muscle activity and impaired spinal locomotor control hampering coordinated movement is a hallmark of spasticity and movement disorders like dystonia. While botulinum toxin A (BoNT-A) standard therapy alleviates mentioned symptoms presumably due to its peripheral neuromuscular actions alone, the aim of present study was to examine for the first time the toxin's trans-synaptic activity within central circuits that govern the skilled movement. The rat hindlimb motor pools were targeted by BoNT-A intrasciatic bilateral injection (2 U per nerve), while its trans-synaptic action on premotor inputs was blocked by intrathecal BoNT-A-neutralising antitoxin (5 i.u.). Effects of BoNT-A on coordinated and high intensity motor tasks (rotarod, beamwalk swimming), and localised muscle weakness (digit abduction, gait ability) were followed until their substantial recovery by day 56 post BoNT-A. Later, (day 62-77) the BoNT-A effects were examined in unilateral calf muscle spasm evoked by tetanus toxin (TeNT, 1.5 ng). In comparison to peripheral effect alone, combined peripheral and central trans-synaptic BoNT-A action induced a more prominent and longer impairment of different motor tasks, as well as the localised muscle weakness. After near-complete recovery of motor functions, the BoNT-A maintained the ability to reduce the experimental calf spasm evoked by tetanus toxin (TeNT 1.5 ng, day 62) without altering the monosynaptic reflex excitability. These results indicate that, in addition to muscle terminals, BoNT-A-mediated control of hyperactive muscle activity in movement disorders and spasticity may involve the spinal premotor inputs and central circuits participating in the skilled locomotor performance.
Collapse
Affiliation(s)
- Petra Šoštarić
- Laboratory of Molecular Neuropharmacology, Department of Pharmacology and Croatian Institute of Brain Research, University of Zagreb School of Medicine, Šalata 11, 10000, Zagreb, Croatia
| | - Magdalena Matić
- Laboratory of Molecular Neuropharmacology, Department of Pharmacology and Croatian Institute of Brain Research, University of Zagreb School of Medicine, Šalata 11, 10000, Zagreb, Croatia; Division of Neurobiology, Department of Neurology, Medical University of Innsbruck, Innsbruck, Austria
| | - Dalia Nemanić
- Department of Pharmacology, Faculty of Pharmacy and Biochemistry, University of Zagreb, Domagojeva 2, 10 000, Zagreb, Croatia
| | - Željka Lučev Vasić
- University of Zagreb, Faculty of Electrical Engineering and Computing, Zagreb, Croatia
| | - Mario Cifrek
- University of Zagreb, Faculty of Electrical Engineering and Computing, Zagreb, Croatia
| | - Marco Pirazzini
- Department of Biomedical Sciences, University of Padova, via Ugo Bassi 58/B 35131, Padova, Italy; Interdepartmental Research Center of Myology CIR-Myo, University of Padova, Via Ugo Bassi 58/B, 35131, Padova, Italy
| | - Ivica Matak
- Laboratory of Molecular Neuropharmacology, Department of Pharmacology and Croatian Institute of Brain Research, University of Zagreb School of Medicine, Šalata 11, 10000, Zagreb, Croatia.
| |
Collapse
|
3
|
Kondratskyi V, Nawrot P, Szepelska A, Boblewska J, Sowińska I, Sygnowski M, Jędrys W, Bienia G, Kosowski T. The use of Botulinum toxin in various urological conditions. WIADOMOSCI LEKARSKIE (WARSAW, POLAND : 1960) 2024; 77:348-352. [PMID: 38593000 DOI: 10.36740/wlek202402124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
OBJECTIVE Aim: The objective of this review paper is to comprehensively analyze and summarize the current understanding and clinical applications of Botulinum toxin in the field of urology. PATIENTS AND METHODS Materials and Methods: The materials and methods for this review paper involved an extensive literature search on the use of Botulinum toxin in urology. Multiple online databases such as PubMed, Web of Science, and Google Scholar were utilized to gather peer-reviewed articles, clinical trials, and relevant books published within the last decades. A few articles used in the review come from before 21 century because the information is essential to fully describe the topic. Studies were selected based on their relevance to the topic, with a focus on those that reported on the clinical applications of Botulinum toxin in urology - we use information from other review papers, clinical trials and research papers. To expand the database, we have looked through the literature not only in English but also other languages. Thanks to this method we were able to compare the results from different countries and scientific groups all over the world. Data extracted from these sources were then analyzed and synthesized to provide a comprehensive overview of the subject matter. CONCLUSION Conclusions: In conclusion, Botulinum toxin has shown significant promise and utility in the field of urology. Its ability to effectively relax muscles has led to its application in a variety of urological conditions, including NDO, OAB, BPS/IC, DSD, BPH, CPP, and PE. The effectiveness and safety of Botulinum toxin have been demonstrated in numerous studies, providing a robust evidence base for its clinical use. However, further research is needed to optimize the administration methods, dosage, and treatment protocols. Additionally, more randomized controlled trials are required to establish the long-term safety and efficacy of Botulinum toxin, especially for conditions for which the current data is limited. Overall, Botulinum toxin represents a valuable tool in the urologist's armamentarium and is likely to continue to be an area of active research and development in the future.
Collapse
Affiliation(s)
| | - Piotr Nawrot
- WARSZAWSKI UNIWERSYTET MEDYCZNY, WARSZAWA, POLAND
| | - Ada Szepelska
- SZPITAL BIELAŃSKI IM. KS. JERZEGO POPIEŁUSZKI, WARSZAWA, POLAND
| | | | | | | | - Wiktoria Jędrys
- SAMODZIELNY ZESPOŁ PUBLICZNYCH ZAKŁADOW LECZNICTWA OTWARTEGO W PIASECZNIE, WARSZAWA, POLAND
| | | | | |
Collapse
|
4
|
Joensuu M, Syed P, Saber SH, Lanoue V, Wallis TP, Rae J, Blum A, Gormal RS, Small C, Sanders S, Jiang A, Mahrhold S, Krez N, Cousin MA, Cooper‐White R, Cooper‐White JJ, Collins BM, Parton RG, Balistreri G, Rummel A, Meunier FA. Presynaptic targeting of botulinum neurotoxin type A requires a tripartite PSG-Syt1-SV2 plasma membrane nanocluster for synaptic vesicle entry. EMBO J 2023; 42:e112095. [PMID: 37226896 PMCID: PMC10308369 DOI: 10.15252/embj.2022112095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 04/18/2023] [Accepted: 04/28/2023] [Indexed: 05/26/2023] Open
Abstract
The unique nerve terminal targeting of botulinum neurotoxin type A (BoNT/A) is due to its capacity to bind two receptors on the neuronal plasma membrane: polysialoganglioside (PSG) and synaptic vesicle glycoprotein 2 (SV2). Whether and how PSGs and SV2 may coordinate other proteins for BoNT/A recruitment and internalization remains unknown. Here, we demonstrate that the targeted endocytosis of BoNT/A into synaptic vesicles (SVs) requires a tripartite surface nanocluster. Live-cell super-resolution imaging and electron microscopy of catalytically inactivated BoNT/A wildtype and receptor-binding-deficient mutants in cultured hippocampal neurons demonstrated that BoNT/A must bind coincidentally to a PSG and SV2 to target synaptic vesicles. We reveal that BoNT/A simultaneously interacts with a preassembled PSG-synaptotagmin-1 (Syt1) complex and SV2 on the neuronal plasma membrane, facilitating Syt1-SV2 nanoclustering that controls endocytic sorting of the toxin into synaptic vesicles. Syt1 CRISPRi knockdown suppressed BoNT/A- and BoNT/E-induced neurointoxication as quantified by SNAP-25 cleavage, suggesting that this tripartite nanocluster may be a unifying entry point for selected botulinum neurotoxins that hijack this for synaptic vesicle targeting.
Collapse
Affiliation(s)
- Merja Joensuu
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain InstituteThe University of QueenslandBrisbaneQLDAustralia
- Queensland Brain InstituteThe University of QueenslandBrisbaneQLDAustralia
- Australian Institute for Bioengineering and NanotechnologyThe University of QueenslandBrisbaneQLDAustralia
| | - Parnayan Syed
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain InstituteThe University of QueenslandBrisbaneQLDAustralia
- Queensland Brain InstituteThe University of QueenslandBrisbaneQLDAustralia
| | - Saber H Saber
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain InstituteThe University of QueenslandBrisbaneQLDAustralia
- Queensland Brain InstituteThe University of QueenslandBrisbaneQLDAustralia
- Australian Institute for Bioengineering and NanotechnologyThe University of QueenslandBrisbaneQLDAustralia
| | - Vanessa Lanoue
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain InstituteThe University of QueenslandBrisbaneQLDAustralia
- Queensland Brain InstituteThe University of QueenslandBrisbaneQLDAustralia
| | - Tristan P Wallis
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain InstituteThe University of QueenslandBrisbaneQLDAustralia
- Queensland Brain InstituteThe University of QueenslandBrisbaneQLDAustralia
| | - James Rae
- Institute for Molecular BioscienceThe University of QueenslandBrisbaneQLDAustralia
| | - Ailisa Blum
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain InstituteThe University of QueenslandBrisbaneQLDAustralia
- Queensland Brain InstituteThe University of QueenslandBrisbaneQLDAustralia
| | - Rachel S Gormal
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain InstituteThe University of QueenslandBrisbaneQLDAustralia
- Queensland Brain InstituteThe University of QueenslandBrisbaneQLDAustralia
| | - Christopher Small
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain InstituteThe University of QueenslandBrisbaneQLDAustralia
- Queensland Brain InstituteThe University of QueenslandBrisbaneQLDAustralia
| | - Shanley Sanders
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain InstituteThe University of QueenslandBrisbaneQLDAustralia
- Queensland Brain InstituteThe University of QueenslandBrisbaneQLDAustralia
| | - Anmin Jiang
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain InstituteThe University of QueenslandBrisbaneQLDAustralia
- Queensland Brain InstituteThe University of QueenslandBrisbaneQLDAustralia
| | - Stefan Mahrhold
- Institut für ToxikologieMedizinische Hochschule HannoverHannoverGermany
| | - Nadja Krez
- Institut für ToxikologieMedizinische Hochschule HannoverHannoverGermany
| | - Michael A Cousin
- Centre for Discovery Brain Sciences, Hugh Robson BuildingUniversity of EdinburghEdinburghUK
- Muir Maxwell Epilepsy CentreUniversity of EdinburghEdinburghUK
- Simons Initiative for the Developing BrainUniversity of EdinburghEdinburghUK
| | - Ruby Cooper‐White
- Australian Institute for Bioengineering and NanotechnologyThe University of QueenslandBrisbaneQLDAustralia
- School of Chemical EngineeringThe University of QueenslandBrisbaneQLDAustralia
| | - Justin J Cooper‐White
- Australian Institute for Bioengineering and NanotechnologyThe University of QueenslandBrisbaneQLDAustralia
- School of Chemical EngineeringThe University of QueenslandBrisbaneQLDAustralia
- UQ Centre for Stem Cell Ageing and Regenerative EngineeringThe University of QueenslandBrisbaneQLDAustralia
| | - Brett M Collins
- Institute for Molecular BioscienceThe University of QueenslandBrisbaneQLDAustralia
| | - Robert G Parton
- Institute for Molecular BioscienceThe University of QueenslandBrisbaneQLDAustralia
- Centre for Microscopy and MicroanalysisThe University of QueenslandBrisbaneQLDAustralia
| | - Giuseppe Balistreri
- Queensland Brain InstituteThe University of QueenslandBrisbaneQLDAustralia
- Department of Virology, Faculty of MedicineUniversity of HelsinkiHelsinkiFinland
| | - Andreas Rummel
- Institut für ToxikologieMedizinische Hochschule HannoverHannoverGermany
| | - Frédéric A Meunier
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain InstituteThe University of QueenslandBrisbaneQLDAustralia
- Queensland Brain InstituteThe University of QueenslandBrisbaneQLDAustralia
- School of Biomedical SciencesThe University of QueenslandBrisbaneQLDAustralia
| |
Collapse
|
5
|
Abstract
Studies in the 1920s found that botulinum neurotoxin type A (BoNT/A) inhibited the activity of motor and parasympathetic nerve endings, confirmed several decades later to be due to decreased acetylcholine release. The 1970s were marked by studies of cellular mechanisms aided by use of neutralizing antibodies as pharmacologic tools: BoNT/A disappeared from accessibility to neutralizing antibodies within minutes, although it took several hours for onset of muscle weakness. The multi-step mechanism was experimentally confirmed and is now recognized to consist broadly of binding to nerve terminals, internalization, and lysis or cleavage of a protein (SNAP-25: synaptosomal associated protein-25 kDa) that is part of the SNARE (Soluble NSF Attachment protein REceptor) complex needed for synaptic vesicle docking and fusion. Clinical use of the BoNT/A product onabotulinumtoxinA was based on its ability to reduce muscle contractions via inhibition of acetylcholine from motor terminals. Sensory mechanisms of onabotulinumtoxinA have now been identified, supporting its successful treatment of chronic migraine and urgency in overactive bladder. Exploration into migraine mechanisms led to anatomical studies documenting pain fibers that send axons through sutures of the skull to outside the head-a potential route by which extracranial injections could affect intracranial processes. Several clinical studies have also identified benefits of onabotulinumtoxinA in major depression, which have been attributed to central responses induced by feedback from facial muscle and skin movement. Overall, the history of BoNT/A is distinguished by basic science studies that stimulated clinical use and, conversely, clinical observations that spurred basic research into novel mechanisms of action.
Collapse
Affiliation(s)
- Mitchell F Brin
- Allergan/AbbVie, Irvine, CA, USA
- University of California, Irvine, CA, USA
| | - Rami Burstein
- Departments of Anesthesia and Neuroscience, Harvard Medical School, Boston, MA, USA
| |
Collapse
|
6
|
Chen S, Li F, Liu G, Li Y, Li Z, Liu Y, Nakanishi H. Construction of a Yeast Cell-Based Assay System to Analyze SNAP25-Targeting Botulinum Neurotoxins. Microorganisms 2023; 11:1125. [PMID: 37317099 DOI: 10.3390/microorganisms11051125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 04/15/2023] [Accepted: 04/21/2023] [Indexed: 06/16/2023] Open
Abstract
Herein, we describe a yeast cell-based assay system to analyze SNAP25-targeting botulinum neurotoxins (BoNTs). BoNTs are protein toxins, and, upon incorporation into neuronal cells, their light chains (BoNT-LCs) target specific synaptosomal N-ethylmaleimide-sensitive attachment protein receptor (SNARE) proteins, including synaptosomal-associated protein 25 (SNAP25). BoNT-LCs are metalloproteases, and each BoNT-LC recognizes and cleaves conserved domains in SNAREs termed the SNARE domain. In the budding yeast Saccharomyces cerevisiae, the SNAP25 ortholog Spo20 is required for production of the spore plasma membrane; thus, defects in Spo20 cause sporulation deficiencies. We found that chimeric SNAREs in which SNARE domains in Spo20 are replaced with those of SNAP25 are functional in yeast cells. The Spo20/SNAP25 chimeras, but not Spo20, are sensitive to digestion by BoNT-LCs. We demonstrate that spo20∆ yeasts harboring the chimeras exhibit sporulation defects when various SNAP25-targeting BoNT-LCs are expressed. Thus, the activities of BoNT-LCs can be assessed by colorimetric measurement of sporulation efficiencies. Although BoNTs are notorious toxins, they are also used as therapeutic and cosmetic agents. Our assay system will be useful for analyzing novel BoNTs and BoNT-like genes, as well as their manipulation.
Collapse
Affiliation(s)
- Shilin Chen
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214126, China
| | - Feng Li
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214126, China
| | - Guoyu Liu
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214126, China
| | - Yuqing Li
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214126, China
| | - Zijie Li
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214126, China
| | - Yishi Liu
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214126, China
| | - Hideki Nakanishi
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214126, China
| |
Collapse
|
7
|
Ambrin G, Cai S, Singh BR. Critical analysis in the advancement of cell-based assays for botulinum neurotoxin. Crit Rev Microbiol 2023; 49:1-17. [PMID: 35212259 DOI: 10.1080/1040841x.2022.2035315] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The study on botulinum neurotoxins (BoNTs) has rapidly evolved for their structure and functions as opposed to them being poisons or cures. Since their discoveries, the scientific community has come a long way in understanding BoNTs' structure and biological activity. Given its current application as a tool for understanding neurocellular activity and as a drug against over 800 neurological disorders, relevant and sensitive assays have become critical for biochemical, physiological, and pharmacological studies. The natural entry of the toxin being ingestion, it has also become important to examine its mechanism while crossing the epithelial cell barrier. Several techniques and methodologies have been developed, for its entry, pharmacokinetics, and biological activity for identification, and drug efficacy both in vivo and in vitro conditions. However, each of them presents its own challenges. The cell-based assay is a platform that exceeds the sensitivity of mouse bioassay while encompassing all the steps of intoxication including cell binding, transcytosis, endocytosis, translocation and proteolytic activity. In this article we review in detail both the neuronal and nonneuronal based cellular interaction of BoNT involving its transportation, and interaction with the targeted cells, and intracellular activities.
Collapse
Affiliation(s)
- Ghuncha Ambrin
- Department of Biomedical Engineering and Biotechnology, University of Massachusetts, Dartmouth, MA, USA.,Department of Chemistry and Biochemistry, University of Massachusetts, Dartmouth, MA, USA
| | - Shuowei Cai
- Department of Chemistry and Biochemistry, University of Massachusetts, Dartmouth, MA, USA
| | - Bal Ram Singh
- Institute of Advanced Sciences, Botulinum Research Center, Dartmouth, MA, USA
| |
Collapse
|
8
|
Gu X, Ding Y, Xiao P, He T. A GHKNN model based on the physicochemical property extraction method to identify SNARE proteins. Front Genet 2022; 13:935717. [PMID: 36506312 PMCID: PMC9727185 DOI: 10.3389/fgene.2022.935717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 11/02/2022] [Indexed: 11/24/2022] Open
Abstract
There is a great deal of importance to SNARE proteins, and their absence from function can lead to a variety of diseases. The SNARE protein is known as a membrane fusion protein, and it is crucial for mediating vesicle fusion. The identification of SNARE proteins must therefore be conducted with an accurate method. Through extensive experiments, we have developed a model based on graph-regularized k-local hyperplane distance nearest neighbor model (GHKNN) binary classification. In this, the model uses the physicochemical property extraction method to extract protein sequence features and the SMOTE method to upsample protein sequence features. The combination achieves the most accurate performance for identifying all protein sequences. Finally, we compare the model based on GHKNN binary classification with other classifiers and measure them using four different metrics: SN, SP, ACC, and MCC. In experiments, the model performs significantly better than other classifiers.
Collapse
Affiliation(s)
- Xingyue Gu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Yijie Ding
- Yangtze Delta Region Institute (Quzhou), University of Electronic Science and Technology of China, Quzhou, Zhejiang, China,Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, China,*Correspondence: Pengfeng Xiao, ; Tao He, ; Yijie Ding,
| | - Pengfeng Xiao
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China,*Correspondence: Pengfeng Xiao, ; Tao He, ; Yijie Ding,
| | - Tao He
- Beidahuang Industry Group General Hospital, Harbin, China,*Correspondence: Pengfeng Xiao, ; Tao He, ; Yijie Ding,
| |
Collapse
|
9
|
Fabris F, Šoštarić P, Matak I, Binz T, Toffan A, Simonato M, Montecucco C, Pirazzini M, Rossetto O. Detection of VAMP Proteolysis by Tetanus and Botulinum Neurotoxin Type B In Vivo with a Cleavage-Specific Antibody. Int J Mol Sci 2022; 23:ijms23084355. [PMID: 35457172 PMCID: PMC9024618 DOI: 10.3390/ijms23084355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 04/08/2022] [Accepted: 04/12/2022] [Indexed: 11/17/2022] Open
Abstract
Tetanus and Botulinum type B neurotoxins are bacterial metalloproteases that specifically cleave the vesicle-associated membrane protein VAMP at an identical peptide bond, resulting in inhibition of neuroexocytosis. The minute amounts of these neurotoxins commonly used in experimental animals are not detectable, nor is detection of their VAMP substrate sensitive enough. The immune detection of the cleaved substrate is much more sensitive, as we have previously shown for botulinum neurotoxin type A. Here, we describe the production in rabbit of a polyclonal antibody raised versus a peptide encompassing the 13 residues C-terminal with respect to the neurotoxin cleavage site. The antibody was affinity purified and found to recognize, with high specificity and selectivity, the novel N-terminus of VAMP that becomes exposed after cleavage by tetanus toxin and botulinum toxin type B. This antibody recognizes the neoepitope not only in native and denatured VAMP but also in cultured neurons and in neurons in vivo in neurotoxin-treated mice or rats, suggesting the great potential of this novel tool to elucidate tetanus and botulinum B toxin activity in vivo.
Collapse
Affiliation(s)
- Federico Fabris
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy; (F.F.); (C.M.)
| | - Petra Šoštarić
- Department of Pharmacology, School of Medicine, University of Zagreb, Šalata 11, 10000 Zagreb, Croatia; (P.Š.); (I.M.)
| | - Ivica Matak
- Department of Pharmacology, School of Medicine, University of Zagreb, Šalata 11, 10000 Zagreb, Croatia; (P.Š.); (I.M.)
| | - Thomas Binz
- Institute of Cellular Biochemistry, Hannover Medical School, Carl-Neuberg-Straße 1, 30625 Hannover, Germany;
| | - Anna Toffan
- Istituto Zooprofilattico Sperimentale delle Venezie, Viale dell’Università 10, 35020 Legnaro, Italy;
| | - Morena Simonato
- Institute of Neuroscience, Italian Research Council, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy;
| | - Cesare Montecucco
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy; (F.F.); (C.M.)
- Institute of Neuroscience, Italian Research Council, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy;
| | - Marco Pirazzini
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy; (F.F.); (C.M.)
- Interdepartmental Research Center of Myology CIR-Myo, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy
- Correspondence: (M.P.); (O.R.)
| | - Ornella Rossetto
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy; (F.F.); (C.M.)
- Institute of Neuroscience, Italian Research Council, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy;
- Interdepartmental Research Center of Myology CIR-Myo, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy
- Correspondence: (M.P.); (O.R.)
| |
Collapse
|
10
|
Pirazzini M, Montecucco C, Rossetto O. Toxicology and pharmacology of botulinum and tetanus neurotoxins: an update. Arch Toxicol 2022; 96:1521-1539. [PMID: 35333944 PMCID: PMC9095541 DOI: 10.1007/s00204-022-03271-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 02/28/2022] [Indexed: 12/27/2022]
Abstract
Tetanus and botulinum neurotoxins cause the neuroparalytic syndromes of tetanus and botulism, respectively, by delivering inside different types of neurons, metalloproteases specifically cleaving the SNARE proteins that are essential for the release of neurotransmitters. Research on their mechanism of action is intensively carried out in order to devise improved therapies based on antibodies and chemical drugs. Recently, major results have been obtained with human monoclonal antibodies and with single chain antibodies that have allowed one to neutralize the metalloprotease activity of botulinum neurotoxin type A1 inside neurons. In addition, a method has been devised to induce a rapid molecular evolution of the metalloprotease domain of botulinum neurotoxin followed by selection driven to re-target the metalloprotease activity versus novel targets with respect to the SNARE proteins. At the same time, an intense and wide spectrum clinical research on novel therapeutics based on botulinum neurotoxins is carried out, which are also reviewed here.
Collapse
Affiliation(s)
- Marco Pirazzini
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131, Padova, Italy.,Centro Interdipartimentale di Ricerca di Miologia, CIR-Myo, University of Padova, Via U. Bassi 58/B, 35131, Padova, Italy
| | - Cesare Montecucco
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131, Padova, Italy. .,Institute of Neuroscience, National Research Council, Via Ugo Bassi 58/B, 35131, Padova, Italy.
| | - Ornella Rossetto
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131, Padova, Italy.,Centro Interdipartimentale di Ricerca di Miologia, CIR-Myo, University of Padova, Via U. Bassi 58/B, 35131, Padova, Italy.,Institute of Neuroscience, National Research Council, Via Ugo Bassi 58/B, 35131, Padova, Italy
| |
Collapse
|
11
|
Highly Specific Monoclonal Antibody Targeting the Botulinum Neurotoxin Type E Exposed SNAP-25 Neoepitope. Antibodies (Basel) 2022; 11:antib11010021. [PMID: 35323195 PMCID: PMC8944829 DOI: 10.3390/antib11010021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 03/07/2022] [Accepted: 03/13/2022] [Indexed: 12/31/2022] Open
Abstract
Botulinum neurotoxin type E (BoNT/E), the fastest acting toxin of all BoNTs, cleaves the 25 kDa synaptosomal-associated protein (SNAP-25) in motor neurons, leading to flaccid paralysis. The specific detection and quantification of the BoNT/E-cleaved SNAP-25 neoepitope can facilitate the development of cell-based assays for the characterization of anti-BoNT/E antibody preparations. In order to isolate highly specific monoclonal antibodies suitable for the in vitro immuno-detection of the exposed neoepitope, mice and rabbits were immunized with an eight amino acid peptide composed of the C-terminus of the cleaved SNAP-25. The immunized rabbits developed a specific and robust polyclonal antibody response, whereas the immunized mice mostly demonstrated a weak antibody response that could not discriminate between the two forms of SNAP-25. An immune scFv phage-display library was constructed from the immunized rabbits and a panel of antibodies was isolated. The sequence alignment of the isolated clones revealed high similarity between both heavy and light chains with exceptionally short HCDR3 sequences. A chimeric scFv-Fc antibody was further expressed and characterized, exhibiting a selective, ultra-high affinity (pM) towards the SNAP-25 neoepitope. Moreover, this antibody enabled the sensitive detection of cleaved SNAP-25 in BoNT/E treated SiMa cells with no cross reactivity with the intact SNAP-25. Thus, by applying an immunization and selection procedure, we have isolated a novel, specific and high-affinity antibody against the BoNT/E-derived SNAP-25 neoepitope. This novel antibody can be applied in in vitro assays that determine the potency of antitoxin preparations and reduce the use of laboratory animals for these purposes.
Collapse
|
12
|
Cai S, Kumar R, Singh BR. Clostridial Neurotoxins: Structure, Function and Implications to Other Bacterial Toxins. Microorganisms 2021; 9:2206. [PMID: 34835332 PMCID: PMC8618262 DOI: 10.3390/microorganisms9112206] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 10/19/2021] [Accepted: 10/19/2021] [Indexed: 01/20/2023] Open
Abstract
Gram-positive bacteria are ancient organisms. Many bacteria, including Gram-positive bacteria, produce toxins to manipulate the host, leading to various diseases. While the targets of Gram-positive bacterial toxins are diverse, many of those toxins use a similar mechanism to invade host cells and exert their functions. Clostridial neurotoxins produced by Clostridial tetani and Clostridial botulinum provide a classical example to illustrate the structure-function relationship of bacterial toxins. Here, we critically review the recent progress of the structure-function relationship of clostridial neurotoxins, including the diversity of the clostridial neurotoxins, the mode of actions, and the flexible structures required for the activation of toxins. The mechanism clostridial neurotoxins use for triggering their activity is shared with many other Gram-positive bacterial toxins, especially molten globule-type structures. This review also summarizes the implications of the molten globule-type flexible structures to other Gram-positive bacterial toxins. Understanding these highly dynamic flexible structures in solution and their role in the function of bacterial toxins not only fills in the missing link of the high-resolution structures from X-ray crystallography but also provides vital information for better designing antidotes against those toxins.
Collapse
Affiliation(s)
- Shuowei Cai
- Department of Chemistry and Biochemistry, University of Massachusetts Dartmouth, Dartmouth, MA 02747, USA
| | - Raj Kumar
- Botulinum Research Center, Institute of Advanced Sciences, Dartmouth, MA 02747, USA; (R.K.); (B.R.S.)
| | - Bal Ram Singh
- Botulinum Research Center, Institute of Advanced Sciences, Dartmouth, MA 02747, USA; (R.K.); (B.R.S.)
| |
Collapse
|
13
|
Knockin mouse models demonstrate differential contributions of synaptotagmin-1 and -2 as receptors for botulinum neurotoxins. PLoS Pathog 2021; 17:e1009994. [PMID: 34662366 PMCID: PMC8553082 DOI: 10.1371/journal.ppat.1009994] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 10/28/2021] [Accepted: 09/30/2021] [Indexed: 12/11/2022] Open
Abstract
Botulinum neurotoxins (BoNTs) are the most potent toxins known and are also utilized to treat a wide range of disorders including muscle spasm, overactive bladder, and pain. BoNTs' ability to target neurons determines their specificity, potency, and therapeutic efficacy. Homologous synaptic vesicle membrane proteins synaptotagmin-1 (Syt1) and synaptotagmin-2 (Syt2) have been identified as receptors for BoNT family members including BoNT/B, DC, and G, but their contributions at physiologically relevant toxin concentrations in vivo have yet to be validated and established. Here we generated two knockin mutant mouse models containing three designed point-mutations that specifically disrupt BoNT binding in endogenous Syt1 or Syt2, respectively. Utilizing digit abduction score assay by injecting toxins into the leg muscle, we found that Syt1 mutant mice showed similar sensitivity as the wild type mice, whereas Syt2 mutant mice showed reduced sensitivity to BoNT/B, DC, and G, demonstrating that Syt2 is the dominant receptor at skeletal neuromuscular junctions. We further developed an in vivo bladder injection assay for analyzing BoNT action on bladder tissues and demonstrated that Syt1 is the dominant toxin receptor in autonomic nerves controlling bladder tissues. These findings establish the critical role of protein receptors for the potency and specificity of BoNTs in vivo and demonstrate the differential contributions of Syt1 and Syt2 in two sets of clinically relevant target tissues.
Collapse
|
14
|
Duchesne de Lamotte J, Perrier A, Martinat C, Nicoleau C. Emerging Opportunities in Human Pluripotent Stem-Cells Based Assays to Explore the Diversity of Botulinum Neurotoxins as Future Therapeutics. Int J Mol Sci 2021; 22:7524. [PMID: 34299143 PMCID: PMC8308099 DOI: 10.3390/ijms22147524] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 07/02/2021] [Accepted: 07/07/2021] [Indexed: 02/07/2023] Open
Abstract
Botulinum neurotoxins (BoNTs) are produced by Clostridium botulinum and are responsible for botulism, a fatal disorder of the nervous system mostly induced by food poisoning. Despite being one of the most potent families of poisonous substances, BoNTs are used for both aesthetic and therapeutic indications from cosmetic reduction of wrinkles to treatment of movement disorders. The increasing understanding of the biology of BoNTs and the availability of distinct toxin serotypes and subtypes offer the prospect of expanding the range of indications for these toxins. Engineering of BoNTs is considered to provide a new avenue for improving safety and clinical benefit from these neurotoxins. Robust, high-throughput, and cost-effective assays for BoNTs activity, yet highly relevant to the human physiology, have become indispensable for a successful translation of engineered BoNTs to the clinic. This review presents an emerging family of cell-based assays that take advantage of newly developed human pluripotent stem cells and neuronal function analyses technologies.
Collapse
Affiliation(s)
- Juliette Duchesne de Lamotte
- IPSEN Innovation, 91940 Les Ulis, France;
- I-STEM, INSERM UMR861, Université Evry-Paris Saclay, 91100 Corbeil-Essonne, France
| | - Anselme Perrier
- I-STEM, INSERM UMR861, Université Evry-Paris Saclay, 91100 Corbeil-Essonne, France
- Laboratoire des Maladies Neurodégénératives: Mécanismes, Thérapies, Imagerie, CEA/CNRS UMR9199, Université Paris Saclay, 92265 Fontenay-aux-Roses, France
| | - Cécile Martinat
- I-STEM, INSERM UMR861, Université Evry-Paris Saclay, 91100 Corbeil-Essonne, France
| | | |
Collapse
|
15
|
Miyashita SI, Zhang J, Zhang S, Shoemaker CB, Dong M. Delivery of single-domain antibodies into neurons using a chimeric toxin-based platform is therapeutic in mouse models of botulism. Sci Transl Med 2021; 13:13/575/eaaz4197. [PMID: 33408184 DOI: 10.1126/scitranslmed.aaz4197] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Accepted: 05/01/2020] [Indexed: 12/15/2022]
Abstract
Efficient penetration of cell membranes and specific targeting of a cell type represent major challenges for developing therapeutics toward intracellular targets. One example facing these hurdles is to develop post-exposure treatment for botulinum neurotoxins (BoNTs), a group of bacterial toxins (BoNT/A to BoNT/G) that are major potential bioterrorism agents. BoNTs enter motor neurons, block neurotransmitter release, and cause a paralytic disease botulism. Members of BoNTs such as BoNT/A exhibit extremely long half-life within neurons, resulting in persistent paralysis for months, yet there are no therapeutics that can inhibit BoNTs once they enter neurons. Here, we developed a chimeric toxin-based delivery platform by fusing the receptor-binding domain of a BoNT, which targets neurons, with the membrane translocation domain and inactivated protease domain of the recently discovered BoNT-like toxin BoNT/X, which can deliver cargoes across endosomal membranes into the cytosol. A therapeutic protein was then created by fusing a single-domain antibody (nanobody) against BoNT/A with the delivery platform. In vitro characterization demonstrated that nanobodies were delivered into cultured neurons and neutralized BoNT/A in neurons. Administration of this protein in mice shortened duration of local muscle paralysis, restoring muscle function within hours, and rescued mice from systemic toxicity of lethal doses of BoNT/A. Fusion of two nanobodies, one against BoNT/A and the other against BoNT/B, created a multivalent therapeutic protein able to neutralize both BoNT/A and BoNT/B in mice. These studies provide an effective post-exposure treatment for botulism and establish a platform for intracellular delivery of therapeutics targeting cytosolic proteins and processes.
Collapse
Affiliation(s)
- Shin-Ichiro Miyashita
- Department of Urology, Boston Children's Hospital, Boston, MA 02115, USA.,Department of Surgery and Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA
| | - Jie Zhang
- Department of Urology, Boston Children's Hospital, Boston, MA 02115, USA.,Department of Surgery and Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA
| | - Sicai Zhang
- Department of Urology, Boston Children's Hospital, Boston, MA 02115, USA.,Department of Surgery and Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA
| | - Charles B Shoemaker
- Department of Infectious Diseases and Global Health, Cummings School of Veterinary Medicine at Tufts University, North Grafton, MA 01536, USA
| | - Min Dong
- Department of Urology, Boston Children's Hospital, Boston, MA 02115, USA. .,Department of Surgery and Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA
| |
Collapse
|
16
|
Caratelli V, Fillo S, D'Amore N, Rossetto O, Pirazzini M, Moccia M, Avitabile C, Moscone D, Lista F, Arduini F. Paper-based electrochemical peptide sensor for on-site detection of botulinum neurotoxin serotype A and C. Biosens Bioelectron 2021; 183:113210. [PMID: 33852978 DOI: 10.1016/j.bios.2021.113210] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 03/12/2021] [Accepted: 03/28/2021] [Indexed: 12/25/2022]
Abstract
Botulinum neurotoxins (BoNTs) produced by soil bacterium Clostridium botulinum are cause of botulism and listed as biohazard agents, thus rapid screening assays are needed for taking the correct countermeasures in a timely fashion. The gold standard method relies on the mouse lethality assay with a lengthy analysis time, i.e., 2-5 days, hindering the prompt management of food safety and medical diagnosis. Herein, we propose the first paper-based antibody-free sensor for reliable and rapid detection of BoNT/A and BoNT/C, exploiting their cleavage capability toward a synthetic peptide able to mimic the natural substrate SNAP-25. The peptide is labelled with the electroactive molecule methylene blue and immobilized on the paper-based electrode modified with gold nanoparticles. Because BoNT/A and BoNT/C can cleave the peptide with the removal of methylene blue from electrode surface, the presence of these neurotoxins in the sample leads to a signal decrease proportional to BoNT amount. The biosensor developed with the selected peptide and combined with smartphone assisted potentiostat is able to detect both BoNT/A and BoNT/C with a linearity up to 1 nM and a detection limit equal to 10 pM. The applicability of this biosensor was evaluated with spiked samples of orange juice, obtaining recovery values equal to 104 ± 6% and 98 ± 9% for 1 nM and 0.5 nM of BoNT/A, respectively.
Collapse
Affiliation(s)
- Veronica Caratelli
- Tor Vergata University, Department of Chemical Science and Technologies, Via Della Ricerca Scientifica, 00133, Rome, Italy
| | - Silvia Fillo
- Scientific Department, Army Medical Center, Via Santo Stefano Rotondo, 4-00184, Rome, Italy
| | - Nino D'Amore
- Scientific Department, Army Medical Center, Via Santo Stefano Rotondo, 4-00184, Rome, Italy
| | - Ornella Rossetto
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131, Padova, Italy; CNR Institute of Neuroscience, Via Ugo Bassi 58/B, 35131, Padova, Italy
| | - Marco Pirazzini
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131, Padova, Italy
| | - Maria Moccia
- Institute of Crystallography, National Research Council, Department of Chemical Sciences and Materials Technology, Via G. Amendola 122/O, 70126, Bari, Italy
| | - Concetta Avitabile
- Institute of Crystallography, National Research Council, Department of Chemical Sciences and Materials Technology, Via G. Amendola 122/O, 70126, Bari, Italy
| | - Danila Moscone
- Tor Vergata University, Department of Chemical Science and Technologies, Via Della Ricerca Scientifica, 00133, Rome, Italy
| | - Florigio Lista
- Scientific Department, Army Medical Center, Via Santo Stefano Rotondo, 4-00184, Rome, Italy
| | - Fabiana Arduini
- Tor Vergata University, Department of Chemical Science and Technologies, Via Della Ricerca Scientifica, 00133, Rome, Italy; SENSE4MED, Via Renato Rascel 30, 00133, Rome, Italy.
| |
Collapse
|
17
|
Giving names to the actors of synaptic transmission: The long journey from synaptic vesicles to neural plasticity. ADVANCES IN PHARMACOLOGY 2021; 90:19-37. [PMID: 33706933 DOI: 10.1016/bs.apha.2020.09.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
More than a scientific paper or a review article, this is a remembrance of a unique time of science and life that the authors spent in Paul Greengard's laboratory at the Rockefeller University in New York in the 1980s and 1990s, forming the so-called synaptic vesicle group. It was a time in which the molecular mechanisms of synaptic transmission and the nature of the organelles in charge of storing and releasing neurotransmitter were just beginning to be understood. It was an exciting time in which the protein composition of synaptic vesicles started to be identified. It turned out that the interactions of synaptic vesicle proteins with the cytoskeleton and the presynaptic membrane and their modulation by protein phosphorylation represented an essential network regulating the efficiency of neurotransmitter release and thereby synaptic strength and plasticity. This is also a description of the distinct scientific journeys that the three authors took on going back to Europe and how they were strongly influenced by the generous and outstanding mentorship of Paul Greengard, his genuine interest in their lives and careers and the life-long friendship with him.
Collapse
|
18
|
The 25 kDa H CN Domain of Clostridial Neurotoxins Is Indispensable for Their Neurotoxicity. Toxins (Basel) 2020; 12:toxins12120743. [PMID: 33255952 PMCID: PMC7760224 DOI: 10.3390/toxins12120743] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 11/13/2020] [Accepted: 11/20/2020] [Indexed: 11/17/2022] Open
Abstract
The extraordinarily potent clostridial neurotoxins (CNTs) comprise tetanus neurotoxin (TeNT) and the seven established botulinum neurotoxin serotypes (BoNT/A-G). They are composed of four structurally independent domains: the roles of the catalytically active light chain, the translocation domain HN, and the C-terminal receptor binding domain HCC are largely resolved, but that of the HCN domain sandwiched between HN and HCC has remained unclear. Here, mutants of BoNT/A, BoNT/B, and TeNT were generated by deleting their HCN domains or swapping HCN domains between each other. Both deletion and replacement of TeNT HCN domain by HCNA and HCNB reduced the biological activity similarly, by ~95%, whereas BoNT/A and B deletion mutants displayed >500-fold reduced activity in the mouse phrenic nerve hemidiaphragm assay. Swapping HCN domains between BoNT/A and B hardly impaired their biological activity, but substitution with HCNT did. Binding assays revealed that in the absence of HCN, not all receptor binding sites are equally well accessible. In conclusion, the presence of HCN is vital for CNTs to exert their neurotoxicity. Although structurally similar, the HCN domain of TeNT cannot equally substitute those of BoNT and vice versa, leaving the possibility that HCNT plays a different role in the intoxication mechanism of TeNT.
Collapse
|
19
|
Winner BM, Bodt SML, McNutt PM. Special Delivery: Potential Mechanisms of Botulinum Neurotoxin Uptake and Trafficking within Motor Nerve Terminals. Int J Mol Sci 2020; 21:ijms21228715. [PMID: 33218099 PMCID: PMC7698961 DOI: 10.3390/ijms21228715] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 11/11/2020] [Accepted: 11/16/2020] [Indexed: 02/06/2023] Open
Abstract
Botulinum neurotoxins (BoNTs) are highly potent, neuroparalytic protein toxins that block the release of acetylcholine from motor neurons and autonomic synapses. The unparalleled toxicity of BoNTs results from the highly specific and localized cleavage of presynaptic proteins required for nerve transmission. Currently, the only pharmacotherapy for botulism is prophylaxis with antitoxin, which becomes progressively less effective as symptoms develop. Treatment for symptomatic botulism is limited to supportive care and artificial ventilation until respiratory function spontaneously recovers, which can take weeks or longer. Mechanistic insights into intracellular toxin behavior have progressed significantly since it was shown that toxins exploit synaptic endocytosis for entry into the nerve terminal, but fundamental questions about host-toxin interactions remain unanswered. Chief among these are mechanisms by which BoNT is internalized into neurons and trafficked to sites of molecular toxicity. Elucidating how receptor-bound toxin is internalized and conditions under which the toxin light chain engages with target SNARE proteins is critical for understanding the dynamics of intoxication and identifying novel therapeutics. Here, we discuss the implications of newly discovered modes of synaptic vesicle recycling on BoNT uptake and intraneuronal trafficking.
Collapse
Affiliation(s)
- Brittany M. Winner
- United States Army Medical Research Institute of Chemical Defense, Gunpowder, MD 21047, USA;
| | - Skylar M. L. Bodt
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, PA 17033, USA;
| | - Patrick M. McNutt
- Wake Forest Institute for Regenerative Medicine, Wake Forest University, Winston-Salem, NC 27101, USA
- Correspondence:
| |
Collapse
|
20
|
Thompson Gray AD, Simonetti J, Adegboye F, Jones CK, Zurawski Z, Hamm HE. Sexual Dimorphism in Stress-induced Hyperthermia in SNAP25Δ3 mice, a mouse model with disabled Gβγ regulation of the exocytotic fusion apparatus. Eur J Neurosci 2020; 52:2815-2826. [PMID: 32449556 DOI: 10.1111/ejn.14836] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 05/14/2020] [Accepted: 05/18/2020] [Indexed: 11/28/2022]
Abstract
Behavioral assays in the mouse can show marked differences between male and female animals of a given genotype. These differences identified in such preclinical studies may have important clinical implications. We recently made a mouse model with impaired presynaptic inhibition through Gβγ-SNARE signaling. Here, we examine the role of sexual dimorphism in the severity of the phenotypes of this model, the SNAP25Δ3 mouse. In males, we already reported that SNAP25Δ3 homozygotes demonstrated phenotypes in motor coordination, nociception, spatial memory and stress processing. We now report that while minimal sexually dimorphic effects were observed for the nociceptive, motor or memory phenotypes, large differences were observed in the stress-induced hyperthermia paradigm, with male SNAP25Δ3 homozygotes exhibiting an increase in body temperature subsequent to handling relative to wild-type littermates, while no such genotype-dependent effect was observed in females. This suggests sexually dimorphic mechanisms of Gβγ-SNARE signaling for stress processing or thermoregulation within the mouse. Second, we examined the effects of heterozygosity with respect to the SNAP25Δ3 mutation. Heterozygote SNAP25Δ3 animals were tested alongside homozygote and wild-type littermates in all of the aforementioned paradigms and displayed phenotypes similar to wild-type animals or an intermediate state. From this, we conclude that the SNAP25Δ3 mutation does not behave in an autosomal dominant manner, but rather displays incomplete dominance for many phenotypes.
Collapse
Affiliation(s)
| | - Justice Simonetti
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| | - Feyisayo Adegboye
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| | - Carrie K Jones
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA.,Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN, USA
| | - Zack Zurawski
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA.,Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA
| | - Heidi E Hamm
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| |
Collapse
|
21
|
Kalb SR, Baudys J, Kiernan K, Wang D, Becher F, Barr JR. Proposed BoNT/A and /B Peptide Substrates Cannot Detect Multiple Subtypes in the Endopep-MS Assay. J Anal Toxicol 2020; 44:173-179. [PMID: 31287544 DOI: 10.1093/jat/bkz044] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 04/24/2019] [Accepted: 04/27/2019] [Indexed: 11/14/2022] Open
Abstract
Botulinum neurotoxins (BoNTs) are a family of protein toxins consisting of seven known serotypes (BoNT/A-BoNT/G) and multiple subtypes within the serotypes, and all of which cause the disease botulism-a disease of great public health concern. Accurate detection of BoNTs in human clinical samples is therefore an important public health goal. To achieve this goal, our laboratory developed a mass spectrometry-based assay detecting the presence of BoNT via its enzymatic activity on a peptide substrate. Recently, publications reported the use of new peptide substrates to detect BoNT/A and /B with improved results over other peptide substrates. However, the authors did not provide results of their peptide substrate on multiple subtypes of BoNT. In this work, we describe the results of testing the new substrates with multiple BoNT/A and /B subtypes and find that the substrates cannot detect many subtypes of BoNT/A and /B.
Collapse
Affiliation(s)
- Suzanne R Kalb
- Division of Laboratory Sciences, Centers for Disease Control and Prevention, National Center for Environmental Health, Buford Hwy, Northeast Atlanta, GA, USA
| | - Jakub Baudys
- Division of Laboratory Sciences, Centers for Disease Control and Prevention, National Center for Environmental Health, Buford Hwy, Northeast Atlanta, GA, USA
| | - Kaitlyn Kiernan
- Division of Laboratory Sciences, Centers for Disease Control and Prevention, National Center for Environmental Health, Buford Hwy, Northeast Atlanta, GA, USA
| | - Dongxia Wang
- Division of Laboratory Sciences, Centers for Disease Control and Prevention, National Center for Environmental Health, Buford Hwy, Northeast Atlanta, GA, USA
| | - François Becher
- Service de Pharmacologie et Immunoanalyse, Laboratoire d'Etude du Métabolisme des Médicaments, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Institut National de la Recherche Agronomique, Université Paris Saclay, Gif-sur-Yvette, France
| | - John R Barr
- Division of Laboratory Sciences, Centers for Disease Control and Prevention, National Center for Environmental Health, Buford Hwy, Northeast Atlanta, GA, USA
| |
Collapse
|
22
|
Leese C, Bresnahan R, Doran C, Simsek D, Fellows AD, Restani L, Caleo M, Schiavo G, Mavlyutov T, Henke T, Binz T, Davletov B. Duplication of clostridial binding domains for enhanced macromolecular delivery into neurons. Toxicon X 2020; 5:100019. [PMID: 32140681 PMCID: PMC7043326 DOI: 10.1016/j.toxcx.2019.100019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 11/25/2019] [Accepted: 12/19/2019] [Indexed: 12/03/2022] Open
Abstract
Neurological diseases constitute a quarter of global disease burden and are expected to rise worldwide with the ageing of human populations. There is an increasing need to develop new molecular systems which can deliver drugs specifically into neurons, non-dividing cells meant to last a human lifetime. Neuronal drug delivery must rely on agents which can recognise neurons with high specificity and affinity. Here we used a recently introduced ‘stapling’ system to prepare macromolecules carrying duplicated binding domains from the clostridial family of neurotoxins. We engineered individual parts of clostridial neurotoxins separately and combined them using a strong alpha-helical bundle. We show that combining two identical binding domains of tetanus and botulinum type D neurotoxins, in a sterically defined way by protein stapling, allows enhanced intracellular delivery of molecules into neurons. We also engineered a botulinum neurotoxin type C variant with a duplicated binding domain which increased enzymatic delivery compared to the native type C toxin. We conclude that duplication of the binding parts of tetanus or botulinum neurotoxins will allow production of high avidity agents which could deliver imaging reagents and large therapeutic enzymes into neurons with superior efficiency. Macromolecules carrying duplicated clostridial binding domains (Hc) were produced. Double tetanus Hc increased protein delivery into cultured rodent neurones. Double tetanus Hc increased enzyme delivery into rodent spinal cord and brain area. Double BoNT/D Hc increased enzyme delivery into rat and human neurones in culture. Recombinant double-Hc BoNT/C was engineered, increasing delivery in cell cultures.
Collapse
Affiliation(s)
- Charlotte Leese
- Department of Biomedical Science, University of Sheffield, Sheffield, S10 2TN, UK
| | - Rebecca Bresnahan
- Department of Biomedical Science, University of Sheffield, Sheffield, S10 2TN, UK
| | - Ciara Doran
- Department of Biomedical Science, University of Sheffield, Sheffield, S10 2TN, UK
| | - Deniz Simsek
- Department of Biomedical Science, University of Sheffield, Sheffield, S10 2TN, UK
| | - Alexander D Fellows
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG, UK
| | - Laura Restani
- CNR Neuroscience Institute, Pisa, 1-56124 Pisa, Italy
| | - Matteo Caleo
- CNR Neuroscience Institute, Pisa, 1-56124 Pisa, Italy
| | - Giampietro Schiavo
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG, UK.,UK Dementia Research Institute, University College London, London, WC1E 6BT, UK
| | - Timur Mavlyutov
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Tina Henke
- Institute of Cellular Biochemistry, Hannover Medical School, Hannover, 30625, Germany
| | - Thomas Binz
- Institute of Cellular Biochemistry, Hannover Medical School, Hannover, 30625, Germany
| | - Bazbek Davletov
- Department of Biomedical Science, University of Sheffield, Sheffield, S10 2TN, UK
| |
Collapse
|
23
|
El-Dakhakhny AS, Gharib T, Issam A, El-Karamany TM. Transperineal intraprostatic injection of botulinum neurotoxin A vs transurethral resection of prostate for management of lower urinary tract symptoms secondary to benign prostate hyperplasia: A prospective randomised study. Arab J Urol 2019; 17:270-278. [PMID: 31723444 PMCID: PMC6830273 DOI: 10.1080/2090598x.2019.1662214] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 07/16/2019] [Indexed: 11/26/2022] Open
Abstract
Objectives: To evaluate transperineal intraprostatic injection of botulinum neurotoxin A (BoNT-A) in patients with lower urinary tract symptoms (LUTS) secondary to benign prostate hyperplasia (BPH) who failed to respond to 6-month medical treatment compared with transurethral resection of the prostate (TURP). Patients and methods: In all, 92 men were divided into TURP and BoNT-A groups after being evaluated using the International Prostate Symptom Score (IPSS) and five-item version of the International Index of Erectile Function, estimation of serum total prostate-specific antigen (tPSA), ultrasonographic estimation of prostatic volume (PV), and uroflowmetry determination of voiding volume (VV), maximum urinary flow rate (Qmax) and post-void residual urine volume (PVR). BoNT-A (200 U diluted in 3 mL saline) was injected, using a 22-G spinal needle under transrectal ultrasonography guidance, with 1-mL in each lobe. Patients were assessed 3-monthly for 12 months. Results: The IPSS significantly decreased in all patients with a non-significant difference between the groups. The mean VV and Qmax increased, whilst PVR, PV and serum tPSA significantly decreased. Patients who showed deterioration at 12 months were re-evaluated and underwent TURP. BoNT-A injection significantly maintained erectile function compared with TURP. Conclusion: Intraprostatic BoNT-A injection reduced PV with subsequent increases in VV and Qmax, and decreases in PVR and serum tPSA level. Intraprostatic BoNT-A injection allowed surgery sparing in >70% and preserved erectile function in 91.3% of patients. Abbreviations: BoNT-A: botulinum neurotoxin A; HRQOL: health-related quality of life; IIEF-5: five-item version of the International Index of Erectile Function; PV: prostatic volume; PVR: post-void residual urine volume; Qmax: maximum urinary flow rate; tPSA: total PSA; VV: voided volume
Collapse
Affiliation(s)
- Amr S El-Dakhakhny
- Department of Urology, Faculty of Medicine, Benha University, Benha, Egypt
| | - Tarek Gharib
- Department of Urology, Faculty of Medicine, Benha University, Benha, Egypt
| | - Ahmed Issam
- Department of Urology, Faculty of Medicine, Minia University, Minia, Egypt
| | | |
Collapse
|
24
|
The SNAP-25 Protein Family. Neuroscience 2019; 420:50-71. [DOI: 10.1016/j.neuroscience.2018.09.020] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Revised: 08/31/2018] [Accepted: 09/14/2018] [Indexed: 01/04/2023]
|
25
|
Farrell R, Baker D. An expert opinion: Optimisation of pharmacological management of multiple sclerosis related spasticity. ADVANCES IN CLINICAL NEUROSCIENCE & REHABILITATION 2019. [DOI: 10.47795/kaib7737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Spasticity is a frequent symptom in people with Multiple Sclerosis. Whilst many respond to first-line therapies it is estimated that 30-40% will have suboptimal treatment response requiring more specialised management. Such strategies include combination of oral medications, botulinum toxin, nabiximols and consideration of intrathecal therapies; baclofen or phenol. Early expert intervention as outlined in this review can have a positive impact on functional ability and quality of life for people with MS.
Collapse
|
26
|
Construction of functional chimeras of syntaxin-1A and its yeast orthologue, and their application to the yeast cell-based assay for botulinum neurotoxin serotype C. Biochim Biophys Acta Gen Subj 2019; 1863:129396. [PMID: 31302181 DOI: 10.1016/j.bbagen.2019.07.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 06/14/2019] [Accepted: 07/10/2019] [Indexed: 11/23/2022]
Abstract
BACKGROUND Botulinum neurotoxins (BoNTs) prevent synaptic transmission because they hydrolyze synaptic N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs). BoNT serotype C (BoNT/C) targets syntaxin-1A and SNAP-25, and is expected to be applied to cosmetic and therapeutic uses. SNAREs are evolutionally conserved proteins and in yeast a syntaxin-1A orthologue Sso1 is involved in exocytosis. The substrate specificity of BoNT/C is strict and it cannot cleave Sso1. METHODS Domain swapping and mutational screenings were performed to generate functional chimeras SNAREs of syntaxin-1A and Sso1. Such chimeras are expressed in yeast cells and assessed whether they are susceptible to BoNT/C digestion. RESULTS The Sso1 and syntaxin-1A chimera (Sso1/STX1A), in which the SNARE domain in Sso1 was replaced with that of syntaxin-1A, was not functional in yeast. The functional incompatibility of Sso1/STX1A was attributable to its accumulation in the ER. We found several mutations that could release Sso1/STX1A from the ER to make the chimera functional in yeast. Yeast cells harboring the mutant chimeras grew similarly to wild-type cells. However, unlike wild-type, yeast harboring the mutant chimeras exhibited a severe growth defect upon expression of BoNT/C. Results of further domain swapping analyses suggest that Sso1 is not digested by BoNT/C because it lacks a binding region to BoNT/C (α-exosite-binding region). CONCLUSIONS We obtained functional Sso1/STX1A chimeras, which can be applied to a yeast cell-based BoNT/C assay. BoNT/C can recognize these chimeras in a similar manner to syntaxin-1A. GENERAL SIGNIFICANCE The yeast cell-based BoNT/C assay would be useful to characterize and engineer BoNT/C.
Collapse
|
27
|
Tsang AR, Rajakumar N, Jog MS. Intrapallidal injection of botulinum toxin A recovers gait deficits in a parkinsonian rodent model. Acta Physiol (Oxf) 2019; 226:e13230. [PMID: 30506881 DOI: 10.1111/apha.13230] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 10/29/2018] [Accepted: 11/24/2018] [Indexed: 12/28/2022]
Abstract
AIM Modulation of electrical activity in the subthalamic nucleus has been therapeutically effective in Parkinson's disease. Pharmacological manipulation of glutamate release from subthalamic neurons could also favourably alter basal ganglia activity to improve motor symptoms. This study investigates the efficacy of selective suppression of hyperactive glutamatergic input from the subthalamic nucleus to the globus pallidus internal segment by botulinum toxin A (BoNT-A) in a parkinsonian model. METHODS Unilateral 6-hydroxydopamine lesioned parkinsonian rodents and controls received microinfusions of BoNT-A or vehicle into the ipsilateral internal globus pallidus (n = 8 per group). Changes in gait were measured by the CatWalk apparatus, along with assessment of apomorphine-induced rotational behaviour prior to and following BoNT-A injection. Immunofluorescent staining for markers of glutamatergic, GABAergic and total terminals was performed at the internal globus pallidus. RESULTS Administration of a single dose of BoNT-A (0.5 ng) significantly improved the rotational asymmetry and gait abnormalities. Ameliorations in speed, body speed variation, cadence and walking pattern were comparable to pre-lesioned animals, and persisted up to 1 month following BoNT-A injection. These changes are associated to BoNT-A's ability to selectively target glutamatergic terminals. CONCLUSION Blockade of subthalamic hyperactivity by BoNT-A leads to sufficient reorganization in the basal ganglia needed to generate a consistent rhythmic pattern of walking. This suggests the potential use of intracerebral BoNT-A to produce effective neuromodulation in the parkinsonian brain, as well as expansion into other neurodegenerative disorders linked to excitotoxity.
Collapse
Affiliation(s)
- Adrianna R. Tsang
- Department of Physiology and Pharmacology Western University London Ontario Canada
| | | | - Mandar S. Jog
- Department of Physiology and Pharmacology Western University London Ontario Canada
- Department of Clinical Neurological Sciences London Health Sciences Centre London Ontario Canada
| |
Collapse
|
28
|
Zurawski Z, Yim YY, Alford S, Hamm HE. The expanding roles and mechanisms of G protein-mediated presynaptic inhibition. J Biol Chem 2019; 294:1661-1670. [PMID: 30710014 PMCID: PMC6364771 DOI: 10.1074/jbc.tm118.004163] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Throughout the past five decades, tremendous advancements have been made in our understanding of G protein signaling and presynaptic inhibition, many of which were published in the Journal of Biological Chemistry under the tenure of Herb Tabor as Editor-in-Chief. Here, we identify these critical advances, including the formulation of the ternary complex model of G protein-coupled receptor signaling and the discovery of Gβγ as a critical signaling component of the heterotrimeric G protein, along with the nature of presynaptic inhibition and its physiological role. We provide an overview for the discovery and physiological relevance of the two known Gβγ-mediated mechanisms for presynaptic inhibition: first, the action of Gβγ on voltage-gated calcium channels to inhibit calcium influx to the presynaptic active zone and, second, the direct binding of Gβγ to the SNARE complex to displace synaptotagmin downstream of calcium entry, which has been demonstrated to be important in neurons and secretory cells. These two mechanisms act in tandem with each other in a synergistic manner to provide more complete spatiotemporal control over neurotransmitter release.
Collapse
Affiliation(s)
- Zack Zurawski
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee 37232-6600; Department of Anatomy and Cell Biology, University of Illinois, Chicago, Illinois 60612-7308
| | - Yun Young Yim
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee 37232-6600
| | - Simon Alford
- Department of Anatomy and Cell Biology, University of Illinois, Chicago, Illinois 60612-7308
| | - Heidi E Hamm
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee 37232-6600.
| |
Collapse
|
29
|
Abstract
Modulation of neurotransmitter exocytosis by activated Gi/o coupled G-protein coupled receptors (GPCRs) is a universal regulatory mechanism used both to avoid overstimulation and to influence circuitry. One of the known modulation mechanisms is the interaction between Gβγ and the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNAREs). There are 5 Gβ and 12 Gγ subunits, but specific Gβγs activated by a given GPCR and the specificity to effectors, such as SNARE, in vivo are not known. Although less studied, Gβγ binding to the exocytic fusion machinery (i.e. SNARE) provides a more direct regulatory mechanism for neurotransmitter release. Here, we review some recent insights in the architecture of the synaptic terminal, modulation of synaptic transmission, and implications of G protein modulation of synaptic transmission in diseases. Numerous presynaptic proteins are involved in the architecture of synaptic terminals, particularly the active zone, and their importance in the regulation of exocytosis is still not completely understood. Further understanding of the Gβγ-SNARE interaction and the architecture and mechanisms of exocytosis may lead to the discovery of novel therapeutic targets to help patients with various disorders such as hypertension, attention-deficit/hyperactivity disorder, post-traumatic stress disorder, and acute/chronic pain.
Collapse
Affiliation(s)
- Yun Young Yim
- Department of Pharmacology, Vanderbilt University, Nashville 37232-6600, TN, United States
| | - Zack Zurawski
- Department of Pharmacology, Vanderbilt University, Nashville 37232-6600, TN, United States
| | - Heidi Hamm
- Department of Pharmacology, Vanderbilt University, Nashville 37232-6600, TN, United States.
| |
Collapse
|
30
|
A novel protein binding strategy for energy-transfer-based photoelectrochemical detection of enzymatic activity of botulinum neurotoxin A. Electrochem commun 2018. [DOI: 10.1016/j.elecom.2018.11.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
|
31
|
Torgeman A, Schwartz A, Diamant E, Baruchi T, Dor E, Ben David A, Pass A, Barnea A, Tal A, Rosner A, Rosen O, Zichel R. Studying the differential efficacy of postsymptom antitoxin treatment in type A versus type B botulism using a rabbit spirometry model. Dis Model Mech 2018; 11:dmm.035089. [PMID: 30115749 PMCID: PMC6177009 DOI: 10.1242/dmm.035089] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 07/30/2018] [Indexed: 11/20/2022] Open
Abstract
Botulinum neurotoxin (BoNT) serotypes A, B and E are responsible for most cases of human botulism. The only approved therapy for botulism is antitoxin treatment administered to patients after symptom onset. However, a recent meta-analysis of antitoxin efficacy in human botulism cases over the past century concluded that a statistically significant reduction in mortality is associated with the use of type E and type A antitoxin, but not with type B antitoxin. Animal models could be highly valuable in studying postsymptom antitoxin efficacy (PSAE). However, the few attempts to evaluate PSAE in animals relied on subjective observations and showed ∼50% protection. Recently, we developed a novel spirometry model for the quantitative evaluation of PSAE in rabbits and used it to demonstrate full protection against BoNT/E. In the current study, a comparative evaluation of PSAE in botulism types A and B was conducted using this quantitative respiratory model. A lethal dose of each toxin induced a comparable course of disease both in terms of time to symptoms (TTS, 41.9±1.3 and 40.6±1.1 h, respectively) and of time to death (TTD, 71.3±3.1 and 66.3±1.7 h, respectively). However, in accordance with the differential serotypic PSAE observed in humans, postsymptom antitoxin treatment was fully effective only in BoNT/A-intoxicated rabbits. This serotypic divergence was reflected by a positive and statistically significant correlation between TTS and TTD in BoNT/A-intoxicated rabbits (r=0.91, P=0.0006), but not in those intoxicated with BoNT/B (r=0.06, P=0.88). The rabbit spirometry system might be useful in the evaluation toolkit of botulism therapeutics, including those under development and intended to act when antitoxin is no longer effective. Summary: Here, we used a quantitative rabbit respiratory model to study the human-related, differential antitoxin efficacy observed in type A and type B botulism.
Collapse
Affiliation(s)
- Amram Torgeman
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel
| | - Arieh Schwartz
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel
| | - Eran Diamant
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel
| | - Tzadok Baruchi
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel
| | - Eyal Dor
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel
| | - Alon Ben David
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel
| | - Avi Pass
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel
| | - Ada Barnea
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel
| | - Arnon Tal
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel
| | - Amir Rosner
- The Veterinary Center for Pre-clinical Research, Israel Institute for Biological Research, Ness Ziona 7410001, Israel
| | - Osnat Rosen
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel
| | - Ran Zichel
- Department of Biotechnology, Israel Institute for Biological Research, Ness Ziona 7410001, Israel
| |
Collapse
|
32
|
Pirazzini M, Carle S, Barth H, Rossetto O, Montecucco C. Primary resistance of human patients to botulinum neurotoxins A and B. Ann Clin Transl Neurol 2018; 5:971-975. [PMID: 30128321 PMCID: PMC6093845 DOI: 10.1002/acn3.586] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 05/08/2018] [Indexed: 11/13/2022] Open
Abstract
Botulinum neurotoxin serotypes A and B are successfully used to treat a variety of human diseases characterized by hyperactive peripheral nerve terminals. However, a number of patients are primary resistant to these pharmaceuticals, without having antitoxin‐neutralizing antibodies. A straightforward explanation of this phenomenon posits that mutations of the toxin sites of interaction with their receptors or protein substrates prevent their neuroparalytic action. After a careful investigation of available human genomic databases, we conclude that it is very unlikely that humans are resistant to these two therapeutic neurotoxins because of mutations that would affect their binding or intracellular proteolytic actions.
Collapse
Affiliation(s)
- Marco Pirazzini
- Department of Biomedical Sciences University of Padova Via Ugo Bassi 58/B 35131 Padova Italy
| | - Stefan Carle
- Institute of Pharmacology and Toxicology University of Ulm Medical Center Albert-Einstein-Allee 11 89081 Ulm Germany
| | - Holger Barth
- Institute of Pharmacology and Toxicology University of Ulm Medical Center Albert-Einstein-Allee 11 89081 Ulm Germany
| | - Ornella Rossetto
- Department of Biomedical Sciences University of Padova Via Ugo Bassi 58/B 35131 Padova Italy
| | - Cesare Montecucco
- Department of Biomedical Sciences University of Padova Via Ugo Bassi 58/B 35131 Padova Italy.,Institute for Neuroscience National Research Council Via Ugo Bassi 58/B 35131 Padova Italy
| |
Collapse
|
33
|
Sharma S, Lindau M. The fusion pore, 60 years after the first cartoon. FEBS Lett 2018; 592:3542-3562. [PMID: 29904915 DOI: 10.1002/1873-3468.13160] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 06/07/2018] [Accepted: 06/12/2018] [Indexed: 11/10/2022]
Abstract
Neurotransmitter release occurs in the form of quantal events by fusion of secretory vesicles with the plasma membrane, and begins with the formation of a fusion pore that has a conductance similar to that of a large ion channel or gap junction. In this review, we propose mechanisms of fusion pore formation and discuss their implications for fusion pore structure and function. Accumulating evidence indicates a direct role of soluble N-ethylmaleimide-sensitive-factor attachment receptor proteins in the opening of fusion pores. Fusion pores are likely neither protein channels nor purely lipid, but are of proteolipidic composition. Future perspectives to gain better insight into the molecular structure of fusion pores are discussed.
Collapse
Affiliation(s)
- Satyan Sharma
- Laboratory for Nanoscale Cell Biology, Max-Planck-Institute for Biophysical Chemistry, Göttingen, Germany
| | - Manfred Lindau
- Laboratory for Nanoscale Cell Biology, Max-Planck-Institute for Biophysical Chemistry, Göttingen, Germany.,School of Applied and Engineering Physics, Cornell University, Ithaca, NY, USA
| |
Collapse
|
34
|
Light Chain Diversity among the Botulinum Neurotoxins. Toxins (Basel) 2018; 10:toxins10070268. [PMID: 30004421 PMCID: PMC6070880 DOI: 10.3390/toxins10070268] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 06/19/2018] [Accepted: 06/21/2018] [Indexed: 12/30/2022] Open
Abstract
Botulinum neurotoxins (BoNT) are produced by several species of clostridium. There are seven immunologically unique BoNT serotypes (A⁻G). The Centers for Disease Control classifies BoNTs as 'Category A' select agents and are the most lethal protein toxins for humans. Recently, BoNT-like proteins have also been identified in several non-clostridia. BoNTs are di-chain proteins comprised of an N-terminal zinc metalloprotease Light Chain (LC) and a C-terminal Heavy Chain (HC) which includes the translocation and receptor binding domains. The two chains are held together by a disulfide bond. The LC cleaves Soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs). The cleavage of SNAREs inhibits the fusion of synaptic vesicles to the cell membrane and the subsequent release of acetylcholine, which results in flaccid paralysis. The LC controls the catalytic properties and the duration of BoNT action. This review discusses the mechanism for LC catalysis, LC translocation, and the basis for the duration of LC action. Understanding these properties of the LC may expand the applications of BoNT as human therapies.
Collapse
|
35
|
Ambrin G, Kumar R, Singh BR. Differential endopeptidase activity of different forms of type A botulinum neurotoxin: A unique relationship between the size of the substrate and activity of the enzyme. Toxicon 2018; 144:34-41. [PMID: 29309744 DOI: 10.1016/j.toxicon.2017.12.055] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 12/27/2017] [Accepted: 12/30/2017] [Indexed: 10/18/2022]
Abstract
Botulinum neurotoxins (BoNTs; serotypes A-G) are metalloproteases, which cleave and inactivate cellular proteins essential for neurotransmitter release. In bacterial cultures, BoNTs are secreted as a complex of the neurotoxin and a group of neurotoxin associated proteins (NAPs). Under physiological condition (pH 7.4), this complex is believed to be dissociated to separate the neurotoxin from NAPs. BoNT consists of a 50 kDa light (L) chain (LC or catalytic domain) and a 100 kDa heavy (H) chain (or HC) linked through a disulfide bond and other non-covalent interactions. The cell intoxication involves three major steps; binding, membrane translocation and inhibition of neurotransmitter release. The last step of intoxication, endopeptidase activity, is very unique and specific that can be used for detection of the complex and isolated forms of the toxin. A fluorescent tag-labeled synthetic peptide (SNAPtide) derived from a segment of SNAP-25, an intracellular substrate of BoNT/A, is used to detect and assay the endopeptidase activity of BoNT/A. The detection of the signal is based on the change in the fluorescence energy transfer after selective cleavage of the peptide by the BoNT/A. In this report, we demonstrate that SNAPtide as a commonly used substrate widely differ in reaction with BoNT/A complex, BoNT/A, and BoNT/A light chain. These findings have implications for assays used in detection, and in screening potential inhibitors.
Collapse
Affiliation(s)
- Ghuncha Ambrin
- Department of Chemistry and Biochemistry, University of Massachusetts, North Dartmouth, MA, 02747, USA
| | - Raj Kumar
- Botulinum Research Center, Institute of Advanced Sciences, Dartmouth, MA 02747, USA
| | - Bal Ram Singh
- Department of Chemistry and Biochemistry, University of Massachusetts, North Dartmouth, MA, 02747, USA; Botulinum Research Center, Institute of Advanced Sciences, Dartmouth, MA 02747, USA.
| |
Collapse
|
36
|
Imafuku Y, Enomoto KI, Kataoka H, Ito I, Maeno T. Novel Distinctive Roles of Docking Proteins in Short-term Synaptic Plasticity of Frog Neuromuscular Transmission Revealed by Botulinum Neurotoxins. Neuroscience 2018; 369:374-385. [PMID: 29175153 DOI: 10.1016/j.neuroscience.2017.11.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2017] [Revised: 10/24/2017] [Accepted: 11/14/2017] [Indexed: 10/18/2022]
Abstract
Short-term synaptic plasticity (SSP) is a basic mechanism for temporal processing of neural information in synaptic transmission. Facilitation, the fastest component of SSP, has been extensively investigated with regard to Ca2+ signaling and other relevant substances. However, systematic analyses on the slower components of SSP, originated by Magleby and Zengel, have remained stagnant for decades, as few chemicals directly modifying these slower components have been identified. In combination with refined experimental protocols designed to study the stimulation frequency-dependence of SSP and botulinum neurotoxins A and C (BoNT-A and BoNT-C), we investigated SSP of frog neuromuscular transmission to clarify the roles of synaptosomal-associated protein of 25 kDa (SNAP-25) and syntaxin, SNARE proteins exclusively participating in vesicular events including docking, priming and exocytosis. We found that BoNT-A treatment eliminated slow potentiation, and BoNT-C poisoning abolished intermediate augmentation, two components of SSP. Fast facilitation was maintained after double poisoning with BoNT-A and -C, but the postsynaptic response became biphasic. A novel depression, termed repression, emerged by double poisoning. Repression was different from depletion because it developed even at a low-frequency stimulation of 1 Hz. We conclude that SNAP-25 and syntaxin not only play roles as cooperative exocytotic machinery, but also have roles in SSP.
Collapse
Affiliation(s)
- Yasuhiro Imafuku
- Department of Biology, Faculty of Science, Kyushu University, Fukuoka 819-0395, Japan.
| | - Koh-Ichi Enomoto
- Department of Physiology, Faculty of Medicine, Shimane University, Izumo 693-8501, Japan
| | - Hiroko Kataoka
- Department of Physiology, Faculty of Medicine, Shimane University, Izumo 693-8501, Japan
| | - Isao Ito
- Department of Biology, Faculty of Science, Kyushu University, Fukuoka 819-0395, Japan
| | - Takashi Maeno
- Professor emeritus at Shimane Medical University (present Faculty of Medicine, Shimane University), Izumo 693-8501, Japan
| |
Collapse
|
37
|
Carle S, Pirazzini M, Rossetto O, Barth H, Montecucco C. High Conservation of Tetanus and Botulinum Neurotoxins Cleavage Sites on Human SNARE Proteins Suggests That These Pathogens Exerted Little or No Evolutionary Pressure on Humans. Toxins (Basel) 2017; 9:toxins9120404. [PMID: 29257047 PMCID: PMC5744124 DOI: 10.3390/toxins9120404] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 12/14/2017] [Accepted: 12/15/2017] [Indexed: 01/07/2023] Open
Abstract
The Genome Aggregation Database presently contains >120,000 human genomes. We searched in this database for the presence of mutations at the sites of tetanus (TeNT) and botulinum neurotoxins (BoNTs) cleavages of the three SNARE proteins: VAMP, SNAP-25 and Syntaxin. These mutations could account for some of the BoNT/A resistant patients. At the same time, this approach was aimed at testing the possibility that TeNT and BoNT may have acted as selective agents in the development of resistance to tetanus or botulism. We found that mutations of the SNARE proteins are very rare and concentrated outside the SNARE motif required for the formation of the SNARE complex involved in neuroexocytosis. No changes were found at the BoNT cleavage sites of VAMP and syntaxins and only one very rare mutation was found in the essential C-terminus region of SNAP-25, where Arg198 was replaced with a Cys residue. This is the P1’ cleavage site for BoNT/A and the P1 cleavage site for BoNT/C. We found that the Arg198Cys mutation renders SNAP-25 resistant to BoNT/A. Nonetheless, its low frequency (1.8 × 10−5) indicates that mutations of SNAP-25 at the BoNT/A cleavage site are unlikely to account for the existence of BoNT/A resistant patients. More in general, the present findings indicate that tetanus and botulinum neurotoxins have not acted as selective agents during human evolution as it appears to have been the case for tetanus in rats and chicken.
Collapse
Affiliation(s)
- Stefan Carle
- Institute of Pharmacology and Toxicology, University of Ulm Medical Center, Albert-Einstein-Allee 11, 89081 Ulm, Germany.
| | - Marco Pirazzini
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy.
| | - Ornella Rossetto
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy.
| | - Holger Barth
- Institute of Pharmacology and Toxicology, University of Ulm Medical Center, Albert-Einstein-Allee 11, 89081 Ulm, Germany.
| | - Cesare Montecucco
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy.
- Institute for Neuroscience, National Research Council, Via Ugo Bassi 58/B, 35131 Padova, Italy.
| |
Collapse
|
38
|
Khounlo R, Kim J, Yin L, Shin YK. Botulinum Toxins A and E Inflict Dynamic Destabilization on t-SNARE to Impair SNARE Assembly and Membrane Fusion. Structure 2017; 25:1679-1686.e5. [PMID: 29033286 PMCID: PMC5685167 DOI: 10.1016/j.str.2017.09.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 08/24/2017] [Accepted: 09/12/2017] [Indexed: 01/08/2023]
Abstract
Botulinum toxins (BoNTs) A and E block neurotransmitter release by specifically cleaving the C- terminal ends of SNAP-25, a plasma membrane SNARE protein. Here, we find that SNAP-25A and E, the cleavage products of BoNT A and E, respectively, terminate membrane fusion via completely different mechanisms. Combined studies of single-molecule FRET and single-vesicle fusion assays reveal that SNAP-25E is incapable of supporting SNARE pairing and thus, vesicle docking. In contrast, SNAP-25A facilitates robust SNARE pairing and vesicle docking with somewhat reduced SNARE zippering, which leads to severe impairment of fusion pore opening. The electron paramagnetic resonance results show that the discrepancy between SNAP-25A and E might stem from the extent of the dynamic destabilization of the t-SNARE core at the N-terminal half, which plays a pivotal role in nucleating SNARE complex formation. Thus, the results provide insights into the structure/dynamics-based mechanism by which BoNT A and E impair membrane fusion.
Collapse
Affiliation(s)
- Ryan Khounlo
- Roy J. Carver Department of Biochemistry, Biophysics & Molecular Biology, Iowa State University, Ames, IA 50011, USA
| | - Jaewook Kim
- Roy J. Carver Department of Biochemistry, Biophysics & Molecular Biology, Iowa State University, Ames, IA 50011, USA
| | - Linxiang Yin
- Roy J. Carver Department of Biochemistry, Biophysics & Molecular Biology, Iowa State University, Ames, IA 50011, USA
| | - Yeon-Kyun Shin
- Roy J. Carver Department of Biochemistry, Biophysics & Molecular Biology, Iowa State University, Ames, IA 50011, USA.
| |
Collapse
|
39
|
Yadirgi G, Stickings P, Rajagopal S, Liu Y, Sesardic D. Immuno-detection of cleaved SNAP-25 from differentiated mouse embryonic stem cells provides a sensitive assay for determination of botulinum A toxin and antitoxin potency. J Immunol Methods 2017; 451:90-99. [PMID: 28943257 DOI: 10.1016/j.jim.2017.09.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 09/19/2017] [Accepted: 09/20/2017] [Indexed: 01/12/2023]
Abstract
Botulinum toxin type A is a causative agent of human botulism. Due to high toxicity and ease of production it is classified by the Centres for Disease Control and Prevention as a category A bioterrorism agent. The same serotype, BoNT/A, is also the most widely used in pharmaceutical preparations for treatment of a diverse range of neuromuscular disorders. Traditionally, animals are used to confirm the presence and activity of toxin and to establish neutralizing capabilities of countermeasures in toxin neutralization tests. Cell based assays for BoNT/A have been reported as the most viable alternative to animal models, since they are capable of reflecting all key steps (binding, translocation, internalization and cleavage of intracellular substrate) involved in toxin activity. In this paper we report preliminary development of a simple immunochemical method for specifically detecting BoNT/A cleaved intracellular substrate, SNAP-25, in cell lysates of neurons derived from mouse embryonic stem cells. The assay offers sensitivity of better than 0.1LD50/ml (3fM) which is not matched by other functional assays, including the mouse bioassay, and provides serotype specificity for quantitative detection of BoNT/A and anti-BoNT/A antitoxin. Subject to formal validation, the method described here could potentially be used as a substitute for the mouse bioassay to measure potency and consistency of therapeutic products.
Collapse
Affiliation(s)
- G Yadirgi
- Division of Bacteriology, National Institute for Biological Standards and Control, a center of the Medicines and Healthcare Products Regulatory Agency, South Mimms, Potters Bar, Hertfordshire EN6 3QG, UK.
| | - P Stickings
- Division of Bacteriology, National Institute for Biological Standards and Control, a center of the Medicines and Healthcare Products Regulatory Agency, South Mimms, Potters Bar, Hertfordshire EN6 3QG, UK.
| | - S Rajagopal
- Division of Bacteriology, National Institute for Biological Standards and Control, a center of the Medicines and Healthcare Products Regulatory Agency, South Mimms, Potters Bar, Hertfordshire EN6 3QG, UK.
| | - Y Liu
- Division of Bacteriology, National Institute for Biological Standards and Control, a center of the Medicines and Healthcare Products Regulatory Agency, South Mimms, Potters Bar, Hertfordshire EN6 3QG, UK.
| | - D Sesardic
- Division of Bacteriology, National Institute for Biological Standards and Control, a center of the Medicines and Healthcare Products Regulatory Agency, South Mimms, Potters Bar, Hertfordshire EN6 3QG, UK.
| |
Collapse
|
40
|
Wang Y, Fry HC, Skinner GE, Schill KM, Duncan TV. Detection and Quantification of Biologically Active Botulinum Neurotoxin Serotypes A and B Using a Förster Resonance Energy Transfer-Based Quantum Dot Nanobiosensor. ACS APPLIED MATERIALS & INTERFACES 2017; 9:31446-31457. [PMID: 28840718 DOI: 10.1021/acsami.7b08736] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Botulinum neurotoxin (BoNT) is the most potent toxin known. The ingestion of food contaminated with biologically active BoNT causes foodborne botulism, which can lead to respiratory paralysis, coma, and death after ingestion of as little as 70 μg for a 70 kg human. Because of its lethality and challenges associated with current detection methods, there is an urgent need for highly sensitive rapid screening techniques capable of detecting biologically active BoNT. Here, we describe a Förster resonance energy transfer-based nanobiosensor that uses quantum dots (QDs) and two specific quencher-labeled peptide probes to detect and differentiate two biologically active forms of BoNT, serotypes A and B, which were responsible for 80% of human foodborne botulism cases in the U.S. from 2012 to 2015. Each peptide probe contains an enzymatic cleavage site specific to only one serotype. QDs were selected based on the spectral overlap with the quenchers. In the presence of the target BoNT serotype, the peptide probe is cleaved and the quenching of QD photoluminescence (PL) is reduced, giving a signal that is easily detected by a PL spectrophotometer. This sensor performance was evaluated with light chains of BoNT/A and BoNT/B (LcA and LcB), catalytic domains of the respective serotypes. LcA and LcB were detected in 3 h with limits of detection of 0.2 and 2 ng/mL, respectively. The specificity of the sensor was evaluated, and no cross-reactivity from nontarget serotypes was observed with 2 h of incubation. Because each serotype-specific peptide is conjugated to a QD with a unique emission wavelength, multiple biologically active BoNT serotypes could be detected in one PL spectrum. The sensor was also shown to be responsive to BoNT/A and BoNT/B holotoxins. Good performance of this sensor implies its potential application as a rapid screening method for biologically active BoNT/A and BoNT/B in the laboratory and in the field.
Collapse
Affiliation(s)
- Yun Wang
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration , 6502 S. Archer Road, Bedford Park, Cook County, Illinois 60501, United States
| | - H Christopher Fry
- Center for Nanoscale Materials, Argonne National Laboratory , 9700 S. Cass Avenue, Lemont, DuPage County, Illinois 60439, United States
| | - Guy E Skinner
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration , 6502 S. Archer Road, Bedford Park, Cook County, Illinois 60501, United States
| | - Kristin M Schill
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration , 6502 S. Archer Road, Bedford Park, Cook County, Illinois 60501, United States
| | - Timothy V Duncan
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration , 6502 S. Archer Road, Bedford Park, Cook County, Illinois 60501, United States
| |
Collapse
|
41
|
Zanetti G, Sikorra S, Rummel A, Krez N, Duregotti E, Negro S, Henke T, Rossetto O, Binz T, Pirazzini M. Botulinum neurotoxin C mutants reveal different effects of syntaxin or SNAP-25 proteolysis on neuromuscular transmission. PLoS Pathog 2017; 13:e1006567. [PMID: 28800600 PMCID: PMC5568444 DOI: 10.1371/journal.ppat.1006567] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 08/23/2017] [Accepted: 08/03/2017] [Indexed: 11/30/2022] Open
Abstract
Botulinum neurotoxin serotype C (BoNT/C) is a neuroparalytic toxin associated with outbreaks of animal botulism, particularly in birds, and is the only BoNT known to cleave two different SNARE proteins, SNAP-25 and syntaxin. BoNT/C was shown to be a good substitute for BoNT/A1 in human dystonia therapy because of its long lasting effects and absence of neuromuscular damage. Two triple mutants of BoNT/C, namely BoNT/C S51T/R52N/N53P (BoNT/C α-51) and BoNT/C L200W/M221W/I226W (BoNT/C α-3W), were recently reported to selectively cleave syntaxin and have been used here to evaluate the individual contribution of SNAP-25 and syntaxin cleavage to the effect of BoNT/C in vivo. Although BoNT/C α-51 and BoNT/C α-3W toxins cleave syntaxin with similar efficiency, we unexpectedly found also cleavage of SNAP-25, although to a lesser extent than wild type BoNT/C. Interestingly, the BoNT/C mutants exhibit reduced lethality compared to wild type toxin, a result that correlated with their residual activity against SNAP-25. In spite of this, a local injection of BoNT/C α-51 persistently impairs neuromuscular junction activity. This is due to an initial phase in which SNAP-25 cleavage causes a complete blockade of neurotransmission, and to a second phase of incomplete impairment ascribable to syntaxin cleavage. Together, these results indicate that neuroparalysis of BoNT/C at the neuromuscular junction is due to SNAP-25 cleavage, while the proteolysis of syntaxin provides a substantial, but incomplete, neuromuscular impairment. In light of this evidence, we discuss a possible clinical use of BoNT/C α-51 as a botulinum neurotoxin endowed with a wide safety margin and a long lasting effect. The seven established Botulinum Neurotoxins serotypes (BoNT/A to G) and the many BoNT subtypes, the causative agents of botulism, are the most poisonous substances known (lethal doses in the low ng/kg range). Due to their toxicological properties, BoNTs are Janus-faced toxins: potent pathogenic factors and potential bioterrorism agents as well as safe and efficacious therapeutics. BoNTs exert their neuroparalytic action by cleaving SNARE proteins, either SNAP-25 or synaptobrevin/VAMP, which mediate neurotransmitter release at the neuromuscular junction; BoNT/C is the only serotype shown to cleave SNAP-25 and syntaxin-1 in vitro. Our study shows for the first time that this parallel cleavage also occurs in vivo. By using mutated toxins reported to be syntaxin-selective, we found that SNAP-25 proteolysis at the neuromuscular junction is the key determinant of BoNT/C lethality as it completely blocks nerve-muscle transmission. Conversely, syntaxin-1 cleavage only attenuates nerve terminal activity without inactivating the synapse, leading to only a partial decrease of neuromuscular functionality. As a result, the BoNT/C mutants have dramatically reduced lethality, but still modulate neuromuscular junction activity upon intramuscular injection. This aspect is particularly relevant considering the possible use of syntaxin-specific BoNT/C derivatives to improve the present clinical utilization of BoNTs.
Collapse
Affiliation(s)
- Giulia Zanetti
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Stefan Sikorra
- Institut für Zellbiochemie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Andreas Rummel
- Institut für Toxikologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Nadja Krez
- Institut für Toxikologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Elisa Duregotti
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Samuele Negro
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Tina Henke
- Institut für Zellbiochemie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Ornella Rossetto
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Thomas Binz
- Institut für Zellbiochemie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Marco Pirazzini
- Department of Biomedical Sciences, University of Padova, Padova, Italy
- * E-mail:
| |
Collapse
|
42
|
Cobianchi S, Jaramillo J, Luvisetto S, Pavone F, Navarro X. Botulinum neurotoxin A promotes functional recovery after peripheral nerve injury by increasing regeneration of myelinated fibers. Neuroscience 2017; 359:82-91. [PMID: 28716587 DOI: 10.1016/j.neuroscience.2017.07.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 07/05/2017] [Accepted: 07/06/2017] [Indexed: 12/28/2022]
Abstract
The injection of safe doses of botulinum neurotoxin A (BoNT/A) have been reported to be useful for the treatment of neuropathic pain, but it is still unknown how functional recovery is induced after peripheral nerve injury. We evaluated the effects of intranerve application of BoNT/A, on regeneration and sensorimotor functional recovery in partial and complete peripheral nerve injuries in the mouse. After sciatic nerve crush (SNC) and intranerve delivery of BoNT/A (15pg), axonal regeneration was measured by nerve pinch test at different days. Regeneration of myelinated and unmyelinated fibers was assessed by immunohistochemical double labeling for NF200/GAP43 and CGRP/GAP43. S100 was used as Schwann cells marker. Medial footpad skin reinnervation was assessed by PGP staining. Motor functions were assessed by means of nerve conduction tests. In other mice groups, nerve conduction tests were performed also after chronic constriction injury (CCI) of the sciatic nerve and intraplantar injection of BoNT/A (15pg). In SNC mice, BoNT/A increased the rate of axonal regeneration. The advantage of regrowing myelinated axons after BoNT/A injection was evidenced by longer NF200+ nerve profiles and confirmed by nerve histology. We observed also a higher expression of S100 in the distal portion of BoNT/A-injected regenerated nerves. In CCI mice, BoNT/A induced an increase in reinnervation of gastrocnemius and plantar muscles. These results show that a low dose of BoNT/A, insufficient to produce muscular dysfunction, conversely speeds up sensorimotor recovery by stimulating myelinated axonal regeneration, and points out its application as a multipotent treatment for peripheral neuropathies.
Collapse
Affiliation(s)
- Stefano Cobianchi
- Institute of Neurosciences and Department of Cell Biology, Physiology and Immunology, Universitat Autonoma de Barcelona, and Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Bellaterra, Spain.
| | - Jessica Jaramillo
- Institute of Neurosciences and Department of Cell Biology, Physiology and Immunology, Universitat Autonoma de Barcelona, and Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Bellaterra, Spain
| | - Siro Luvisetto
- CNR-National Research Council, Institute of Cell Biology and Neurobiology, Rome, Italy; IRCCS Santa Lucia Foundation, Rome, Italy
| | - Flaminia Pavone
- CNR-National Research Council, Institute of Cell Biology and Neurobiology, Rome, Italy; IRCCS Santa Lucia Foundation, Rome, Italy
| | - Xavier Navarro
- Institute of Neurosciences and Department of Cell Biology, Physiology and Immunology, Universitat Autonoma de Barcelona, and Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Bellaterra, Spain
| |
Collapse
|
43
|
Pirazzini M, Rossetto O, Eleopra R, Montecucco C. Botulinum Neurotoxins: Biology, Pharmacology, and Toxicology. Pharmacol Rev 2017; 69:200-235. [PMID: 28356439 PMCID: PMC5394922 DOI: 10.1124/pr.116.012658] [Citation(s) in RCA: 410] [Impact Index Per Article: 58.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The study of botulinum neurotoxins (BoNT) is rapidly progressing in many aspects.
Novel BoNTs are being discovered owing to next generation sequencing, but their
biologic and pharmacological properties remain largely unknown. The molecular
structure of the large protein complexes that the toxin forms with accessory
proteins, which are included in some BoNT type A1 and B1 pharmacological
preparations, have been determined. By far the largest effort has been dedicated to
the testing and validation of BoNTs as therapeutic agents in an ever increasing
number of applications, including pain therapy. BoNT type A1 has been also exploited
in a variety of cosmetic treatments, alone or in combination with other agents, and
this specific market has reached the size of the one dedicated to the treatment of
medical syndromes. The pharmacological properties and mode of action of BoNTs have
shed light on general principles of neuronal transport and protein-protein
interactions and are stimulating basic science studies. Moreover, the wide array of
BoNTs discovered and to be discovered and the production of recombinant BoNTs endowed
with specific properties suggest novel uses in therapeutics with increasing
disease/symptom specifity. These recent developments are reviewed here to provide an
updated picture of the biologic mechanism of action of BoNTs, of their increasing use
in pharmacology and in cosmetics, and of their toxicology.
Collapse
Affiliation(s)
- Marco Pirazzini
- Department of Biomedical Sciences, University of Padova, Italy (M.P., O.R., C.M.); Neurologic Department, University-Hospital S. Maria della Misericordia, Udine, Italy (R.E.); and Consiglio Nazionale delle Ricerche, Institute of Neuroscience, University of Padova, Italy (C.M.)
| | - Ornella Rossetto
- Department of Biomedical Sciences, University of Padova, Italy (M.P., O.R., C.M.); Neurologic Department, University-Hospital S. Maria della Misericordia, Udine, Italy (R.E.); and Consiglio Nazionale delle Ricerche, Institute of Neuroscience, University of Padova, Italy (C.M.)
| | - Roberto Eleopra
- Department of Biomedical Sciences, University of Padova, Italy (M.P., O.R., C.M.); Neurologic Department, University-Hospital S. Maria della Misericordia, Udine, Italy (R.E.); and Consiglio Nazionale delle Ricerche, Institute of Neuroscience, University of Padova, Italy (C.M.)
| | - Cesare Montecucco
- Department of Biomedical Sciences, University of Padova, Italy (M.P., O.R., C.M.); Neurologic Department, University-Hospital S. Maria della Misericordia, Udine, Italy (R.E.); and Consiglio Nazionale delle Ricerche, Institute of Neuroscience, University of Padova, Italy (C.M.)
| |
Collapse
|
44
|
Piotrowska A, Popiolek-Barczyk K, Pavone F, Mika J. Comparison of the Expression Changes after Botulinum Toxin Type A and Minocycline Administration in Lipopolysaccharide-Stimulated Rat Microglial and Astroglial Cultures. Front Cell Infect Microbiol 2017; 7:141. [PMID: 28491822 PMCID: PMC5405066 DOI: 10.3389/fcimb.2017.00141] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 04/06/2017] [Indexed: 12/23/2022] Open
Abstract
Botulinum neurotoxin type A (BoNT/A) and minocycline are potent drugs used in clinical therapies. The primary molecular mechanism of BoNT/A is the cleavage of SNARE proteins, which prevents cells from releasing neurotransmitters from vesicles, while the effects of minocycline are related to the inhibition of p38 activation. Both BoNT/A and minocycline exhibit analgesic effects, however, their direct impact on glial cells is not fully known. Therefore, the aim of the present study was to determine the effects of those drugs on microglial and astroglial activity after lipopolysaccharide (LPS) stimulation and their potential synergistic action. Our results show that BoNT/A and minocycline influenced primary microglial cells by inhibiting intracellular signaling pathways, such as p38, ERK1/2, NF-κB, and the release of pro-inflammatory factors, including IL-1β, IL-18, IL-6, and NOS2. We have revealed that, in contrast to minocycline, BoNT/A treatment did not decrease LPS-induced release of pro-inflammatory factors in the astroglia. In addition, BoNT/A decreased SNAP-23 in both types of glial cells and also SNAP-25 expressed only in astrocytes. Moreover, BoNT/A increased TLR2 and its adaptor protein MyD88, but not TLR4 exclusively in microglial cells. Furthermore, we have shown the impact of BoNT/A on microglial and astroglial cells, with a particular emphasis on its molecular target, TLR2. In contrast, minocycline did not affect any of those factors. We have revealed that despite of different molecular targets, minocycline, and BoNT/A reduced the release of microglia-derived pro-inflammatory factors. In conclusion, we have shown that BoNT/A and minocycline are effective drugs for the management of neuroinflammation by dampening the activation of microglial cells, with minocycline also affecting astroglial activity.
Collapse
Affiliation(s)
- Anna Piotrowska
- Department of Pain Pharmacology, Institute of Pharmacology, Polish Academy of SciencesKrakow, Poland
| | | | - Flaminia Pavone
- CNR, Institute of Cell Biology and NeurobiologyRome, Italy
- IRCCS, Santa Lucia FoundationRome, Italy
| | - Joanna Mika
- Department of Pain Pharmacology, Institute of Pharmacology, Polish Academy of SciencesKrakow, Poland
| |
Collapse
|
45
|
A Presynaptic Group III mGluR Recruits Gβγ/SNARE Interactions to Inhibit Synaptic Transmission by Cone Photoreceptors in the Vertebrate Retina. J Neurosci 2017; 37:4618-4634. [PMID: 28363980 DOI: 10.1523/jneurosci.2948-16.2017] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 03/27/2017] [Accepted: 03/28/2017] [Indexed: 11/21/2022] Open
Abstract
G-protein βγ subunits (Gβγ) interact with presynaptic proteins and regulate neurotransmitter release downstream of Ca2+ influx. To accomplish their roles in sensory signaling, photoreceptor synapses use specialized presynaptic proteins that support neurotransmission at active zone structures known as ribbons. While several G-protein coupled receptors (GPCRs) influence synaptic transmission at ribbon synapses of cones and other retinal neurons, it is unknown whether Gβγ contributes to these effects. We tested whether activation of one particular GPCR, a metabotropic glutamate receptor (mGluR), can reduce cone synaptic transmission via Gβγ in tiger salamander retinas. In recordings from horizontal cells, we found that an mGluR agonist (L-AP4) reduced cone-driven light responses and mEPSC frequency. In paired recordings of cones and horizontal cells, L-AP4 slightly reduced cone ICa (∼10%) and caused a larger reduction in cone-driven EPSCs (∼30%). Proximity ligation assay revealed direct interactions between SNAP-25 and Gβγ subunits in retinal synaptic layers. Pretreatment with the SNAP-25 cleaving protease BoNT/A inhibited L-AP4 effects on synaptic transmission, as did introduction of a peptide derived from the SNAP-25 C terminus. Introducing Gβγ subunits directly into cones reduced EPSC amplitude. This effect was inhibited by BoNT/A, supporting a role for Gβγ/SNAP-25 interactions. However, the mGluR-dependent reduction in ICa was not mimicked by Gβγ, indicating that this effect was independent of Gβγ. The finding that synaptic transmission at cone ribbon synapses is regulated by Gβγ/SNAP-25 interactions indicates that these mechanisms are shared by conventional and ribbon-type synapses. Gβγ liberated from other photoreceptor GPCRs is also likely to regulate synaptic transmission.SIGNIFICANCE STATEMENT Dynamic regulation of synaptic transmission by presynaptic G-protein coupled receptors shapes information flow through neural circuits. At the first synapse in the visual system, presynaptic metabotropic glutamate receptors (mGluRs) regulate cone photoreceptor synaptic transmission, although the mechanisms and functional impact of this are unclear. We show that mGluRs regulate light response encoding across the cone synapse, accomplished in part by triggering G-protein βγ subunits (Gβγ) interactions with SNAP-25, a core component of the synaptic vesicle fusion machinery. In addition to revealing a role in visual processing, this provides the first demonstration that Gβγ/SNAP-25 interactions regulate synaptic function at a ribbon-type synapse, contributing to an emerging picture of the ubiquity of Gβγ/SNARE interactions in regulating synaptic transmission throughout the nervous system.
Collapse
|
46
|
Affiliation(s)
- Dirk Dressler
- Movement Disorders Section, Department of Neurology, Hannover Medical School, Hannover, Germany
| | | |
Collapse
|
47
|
Kasula R, Chai YJ, Bademosi AT, Harper CB, Gormal RS, Morrow IC, Hosy E, Collins BM, Choquet D, Papadopulos A, Meunier FA. The Munc18-1 domain 3a hinge-loop controls syntaxin-1A nanodomain assembly and engagement with the SNARE complex during secretory vesicle priming. J Cell Biol 2016; 214:847-58. [PMID: 27646276 PMCID: PMC5037406 DOI: 10.1083/jcb.201508118] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2015] [Accepted: 08/24/2016] [Indexed: 12/12/2022] Open
Abstract
Kasula et al. use single-molecule imaging to reveal the diffusional signature for the SNARE proteins Munc18-1 and syntaxin-1A during secretory vesicle priming. The authors show that a conformational change in the Munc18-1 domain 3a hinge-loop regulates engagement of syntaxin-1A in the SNARE complex. Munc18-1 and syntaxin-1A control SNARE-dependent neuroexocytosis and are organized in nanodomains on the plasma membrane of neurons and neurosecretory cells. Deciphering the intra- and intermolecular steps via which they prepare secretory vesicles (SVs) for fusion is key to understanding neuronal and hormonal communication. Here, we demonstrate that expression of a priming-deficient mutant lacking 17 residues of the domain 3a hinge-loop (Munc18-1Δ317-333) in PC12 cells engineered to knockdown Munc18-1/2 markedly prolonged SV docking. Single-molecule analysis revealed nonhomogeneous diffusion of Munc18-1 and syntaxin-1A in and out of partially overlapping nanodomains. Whereas Munc18-1WT mobility increased in response to stimulation, syntaxin-1A became less mobile. These Munc18-1 and syntaxin-1A diffusional switches were blocked by the expression of Munc18-1Δ317-333, suggesting that a conformational change in the Munc18-1 hinge-loop controls syntaxin-1A and subsequent SNARE complex assembly. Accordingly, syntaxin-1A confinement was prevented by expression of botulinum neurotoxin type E. The Munc18-1 domain 3a hinge-loop therefore controls syntaxin-1A engagement into SNARE complex formation during priming.
Collapse
Affiliation(s)
- Ravikiran Kasula
- Queensland Brain Institute, Clem Jones Centre for Ageing Dementia Research, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Ye Jin Chai
- Queensland Brain Institute, Clem Jones Centre for Ageing Dementia Research, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Adekunle T Bademosi
- Queensland Brain Institute, Clem Jones Centre for Ageing Dementia Research, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Callista B Harper
- Queensland Brain Institute, Clem Jones Centre for Ageing Dementia Research, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Rachel S Gormal
- Queensland Brain Institute, Clem Jones Centre for Ageing Dementia Research, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Isabel C Morrow
- Queensland Brain Institute, Clem Jones Centre for Ageing Dementia Research, The University of Queensland, Brisbane, Queensland 4072, Australia Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Eric Hosy
- Interdisciplinary Institute for Neuroscience, University of Bordeaux, 33077 Bordeaux, France Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5297, 33077 Bordeaux, France
| | - Brett M Collins
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Daniel Choquet
- Interdisciplinary Institute for Neuroscience, University of Bordeaux, 33077 Bordeaux, France Centre National de la Recherche Scientifique, Unité Mixte de Recherche 5297, 33077 Bordeaux, France Bordeaux Imaging Center, Unité Mixte de Service 3420, Centre National de la Recherche Scientifique, US4 Institut National de la Santé et de la Recherche Médicale, University of Bordeaux, 33077 Bordeaux, France
| | - Andreas Papadopulos
- Queensland Brain Institute, Clem Jones Centre for Ageing Dementia Research, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Frédéric A Meunier
- Queensland Brain Institute, Clem Jones Centre for Ageing Dementia Research, The University of Queensland, Brisbane, Queensland 4072, Australia
| |
Collapse
|
48
|
Neurotoxins from Clostridium botulinum (serotype A) isolated from the soil of Mendoza (Argentina) differ from the A-Hall archetype and from that causing infant botulism. Toxicon 2016; 121:30-35. [PMID: 27527271 DOI: 10.1016/j.toxicon.2016.08.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Revised: 08/10/2016] [Accepted: 08/11/2016] [Indexed: 11/22/2022]
Abstract
The type A of neurotoxin produced by Clostridium botulinum is the prevalent serotype in strains of Mendoza. The soil is the main reservoir for C.botulinum and is possibly one of the infection sources in infant botulism. In this study, we characterized and compared autochthonous C. botulinum strains and their neurotoxins. Bacterial samples were obtained from the soil and from fecal samples collected from children with infant botulism. We first observed differences in the appearance of the colonies between strains from each source and with the A Hall control strain. In addition, purified neurotoxins of both strains were found to be enriched in a band of 300 kDa, whereas the A-Hall strain was mainly made up of a band of ∼600 kDa. This finding is in line with the lack of hemagglutinating activity of the neurotoxins under study. Moreover, the proteolytic activity of C. botulinum neurotoxins was evaluated against SNARE (soluble N-ethylmaleimide-sensitive factor-attachment protein receptor) proteins from rat brain. It was observed that both, SNAP 25 (synaptosomal-associated protein 25) and VAMP 2 (vesicle-associated membrane protein) were cleaved by the neurotoxins isolated from the soil strains, whereas the neurotoxins from infant botulism strains only induced a partial cleavage of VAMP 2. On the other hand, the neurotoxin from the A-Hall strain was able to cleave both proteins, though at a lesser extent. Our data indicate that the C.botulinum strain isolated from the soil, and its BoNT, exhibit different properties compared to the strain obtained from infant botulism patients, and from the A-Hall archetype.
Collapse
|
49
|
Azarnia Tehran D, Pirazzini M, Leka O, Mattarei A, Lista F, Binz T, Rossetto O, Montecucco C. Hsp90 is involved in the entry of clostridial neurotoxins into the cytosol of nerve terminals. Cell Microbiol 2016; 19. [DOI: 10.1111/cmi.12647] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Revised: 07/06/2016] [Accepted: 07/08/2016] [Indexed: 12/31/2022]
Affiliation(s)
- Domenico Azarnia Tehran
- Department of Biomedical Sciences; University of Padova; Via Ugo Bassi 58/B 35121 Padova Italy
| | - Marco Pirazzini
- Department of Biomedical Sciences; University of Padova; Via Ugo Bassi 58/B 35121 Padova Italy
| | - Oneda Leka
- Department of Biomedical Sciences; University of Padova; Via Ugo Bassi 58/B 35121 Padova Italy
| | - Andrea Mattarei
- Department of Chemical Sciences; University of Padova; Via F. Marzolo 1 35131 Padova Italy
| | - Florigio Lista
- Histology and Molecular Biology Section; Army Medical and Veterinary Research Center; Via Santo Stefano Rotondo 4 00184 Rome Italy
| | - Thomas Binz
- Medizinische Hochschule Hannover; Institut für Physiologische Chemie OE4310; 30625 Hannover Germany
| | - Ornella Rossetto
- Department of Biomedical Sciences; University of Padova; Via Ugo Bassi 58/B 35121 Padova Italy
| | - Cesare Montecucco
- Department of Biomedical Sciences; University of Padova; Via Ugo Bassi 58/B 35121 Padova Italy
- National Research Institute of Neuroscience; University of Padova; Via Ugo Bassi 58/B 35121 Padova Italy
| |
Collapse
|
50
|
Botulinum Neurotoxin Serotype A Recognizes Its Protein Receptor SV2 by a Different Mechanism than Botulinum Neurotoxin B Synaptotagmin. Toxins (Basel) 2016; 8:toxins8050154. [PMID: 27196927 PMCID: PMC4885069 DOI: 10.3390/toxins8050154] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 04/28/2016] [Accepted: 05/09/2016] [Indexed: 11/23/2022] Open
Abstract
Botulinum neurotoxins (BoNTs) exhibit extraordinary potency due to their exquisite neurospecificity, which is achieved by dual binding to complex polysialo-gangliosides and synaptic vesicle proteins. The luminal domain 4 (LD4) of the three synaptic vesicle glycoprotein 2 isoforms, SV2A‐C, identified as protein receptors for the most relevant serotype BoNT/A, binds within the 50 kDa cell binding domain HC of BoNT/A. Here, we deciphered the BoNT/A‐SV2 interactions in more detail. In pull down assays, the binding of HCA to SV2-LD4 isoforms decreases from SV2C >> SV2A > SV2B. A binding constant of 200 nM was determined for BoNT/A to rat SV2C-LD4 in GST pull down assay. A similar binding constant was determined by surface plasmon resonance for HCA to rat SV2C and to human SV2C, the latter being slightly lower due to the substitution L563F in LD4. At pH 5, as measured in acidic synaptic vesicles, the binding constant of HCA to hSV2C is increased more than 10-fold. Circular dichroism spectroscopy reveals that the quadrilateral helix of SV2C-LD4 already exists in solution prior to BoNT/A binding. Hence, the BoNT/A‐SV2C interaction is of different nature compared to BoNT/B‐Syt-II. In particular, the preexistence of the quadrilateral β-sheet helix of SV2 and its pH-dependent binding to BoNT/A via backbone–backbone interactions constitute major differences. Knowledge of the molecular details of BoNT/A‐SV2 interactions drives the development of high affinity peptides to counteract BoNT/A intoxications or to capture functional BoNT/A variants in innovative detection systems for botulism diagnostic.
Collapse
|