1
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Kaji R. A look at the future-new BoNTs and delivery systems in development: What it could mean in the clinic. Toxicon 2023; 234:107264. [PMID: 37657515 DOI: 10.1016/j.toxicon.2023.107264] [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: 05/05/2023] [Revised: 08/07/2023] [Accepted: 08/22/2023] [Indexed: 09/03/2023]
Abstract
Despite the expanding clinical utility of botulinum neurotoxins, there remain problems to be solved for attaining the best outcome. The efficacy and safety need to be reconsidered for commercially available preparations all derived from subtype A1 or B1. Emerging new toxins include A2 or A6 subtypes or engineered toxins with less spread, more potency, longer durations of action, less antigenicity and better safety profile than currently used preparations. Non-toxic BoNTs with a few amino acid replacements of the light chain (LC) may have a role as a drug-delivery system if the toxicity is abolished entirely. At present, efficacy of these BoNTs in animal botulism was demonstrated.
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Affiliation(s)
- Ryuji Kaji
- Tokushima University, Department of Clinical Neuroscience, 2-50-1 Kuramoto-cho, Tokushima, 770-8503, Japan.
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2
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A Comprehensive Structural Analysis of Clostridium botulinum Neurotoxin A Cell-Binding Domain from Different Subtypes. Toxins (Basel) 2023; 15:toxins15020092. [PMID: 36828407 PMCID: PMC9966434 DOI: 10.3390/toxins15020092] [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: 12/01/2022] [Revised: 01/11/2023] [Accepted: 01/16/2023] [Indexed: 01/20/2023] Open
Abstract
Botulinum neurotoxins (BoNTs) cause flaccid neuromuscular paralysis by cleaving one of the SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) complex proteins. BoNTs display high affinity and specificity for neuromuscular junctions, making them one of the most potent neurotoxins known to date. There are seven serologically distinct BoNTs (serotypes BoNT/A to BoNT/G) which can be further divided into subtypes (e.g., BoNT/A1, BoNT/A2…) based on small changes in their amino acid sequence. Of these, BoNT/A1 and BoNT/B1 have been utilised to treat various diseases associated with spasticity and hypersecretion. There are potentially many more BoNT variants with differing toxicological profiles that may display other therapeutic benefits. This review is focused on the structural analysis of the cell-binding domain from BoNT/A1 to BoNT/A6 subtypes (HC/A1 to HC/A6), including features such as a ganglioside binding site (GBS), a dynamic loop, a synaptic vesicle glycoprotein 2 (SV2) binding site, a possible Lys-Cys/Cys-Cys bridge, and a hinge motion between the HCN and HCC subdomains. Characterising structural features across subtypes provides a better understanding of how the cell-binding domain functions and may aid the development of novel therapeutics.
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A Pilot Study of A2NTX, a Novel Low-Molecular-Weight Neurotoxin Derived from Subtype A2 for Post-Stroke Lower Limb Spasticity: Comparison with OnabotulinumtoxinA. Toxins (Basel) 2022; 14:toxins14110739. [PMID: 36355989 PMCID: PMC9697926 DOI: 10.3390/toxins14110739] [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: 09/05/2022] [Revised: 10/15/2022] [Accepted: 10/20/2022] [Indexed: 01/26/2023] Open
Abstract
All the currently used type A botulinum neurotoxins for clinical uses are of subtype A1. We compared the efficacy and safety for the first time head-to-head between a novel botulinum toxin A2NTX prepared from subtype A2 and onabotulinumtoxinA (BOTOX) derived from A1 for post-stroke spasticity. We assessed the modified Ashworth scale (MAS) of the ankle joint, the mobility scores of Functional Independence Measure (FIM), and the grip power of the unaffected hand before and after injecting 300 units of BOTOX or A2NTX into calf muscles. The procedure was done in a blinded manner for the patient, the injecting physician, and the examiner. Stroke patients with chronic spastic hemiparesis (15 for A2NTX and 16 for BOTOX) were enrolled, and 11 for A2NTX and 13 for BOTOX (MAS of ankle; > or = 2) were entered for the MAS study. Area-under-curves of changes in MAS (primary outcome) were greater for A2NTX by day 30 (p = 0.044), and were similar by day 60. FIM was significantly improved in the A2NTX group (p = 0.005), but not in the BOTOX group by day 60. The hand grip of the unaffected limb was significantly decreased in the BOTOX-injected group (p = 0.002), but was unaffected in the A2NTX-injected group by day 60, suggesting there was less spread of A2NTX to the upper limb than there was with BOTOX. Being a small-sized pilot investigation with an imbalance in the gender of the subjects, the present study suggested superior efficacy and safety of A2NTX, and warrants a larger scale clinical trial of A2NTX to confirm these preliminary results.
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4
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Kim HR, Jung Y, Shin J, Park M, Kweon DH, Ban C. Neuron-recognizable characteristics of peptides recombined using a neuronal binding domain of botulinum neurotoxin. Sci Rep 2022; 12:4980. [PMID: 35322139 PMCID: PMC8943039 DOI: 10.1038/s41598-022-09145-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 03/14/2022] [Indexed: 11/09/2022] Open
Abstract
Recombinant peptides were designed using the C-terminal domain (receptor binding domain, RBD) and its subdomain (peptide A2) of a heavy chain of botulinum neurotoxin A-type 1 (BoNT/A1), which can bind to the luminal domain of synaptic vesicle glycoprotein 2C (SV2C-LD). Peptide A2- or RBD-containing recombinant peptides linked to an enhanced green fluorescence protein (EGFP) were prepared by expression in Escherichia coli. A pull-down assay using SV2C-LD-covered resins showed that the recombinant peptides for CDC297 BoNT/A1, referred to EGFP-A2' and EGFP-RBD', exhibited ≥ 2.0-times stronger binding affinity to SV2C-LD than those for the wild-type BoNT/A1. Using bio-layer interferometry, an equilibrium dissociation rate constant (KD) of EGFP-RBD' to SV2C-LD was determined to be 5.45 μM, which is 33.87- and 15.67-times smaller than the KD values for EGFP and EGFP-A2', respectively. Based on confocal laser fluorescence micrometric analysis, the adsorption/absorption of EGFP-RBD' to/in differentiated PC-12 cells was 2.49- and 1.29-times faster than those of EGFP and EGFP-A2', respectively. Consequently, the recombinant peptides acquired reasonable neuron-specific binding/internalizing ability through the recruitment of RBD'. In conclusion, RBDs of BoNTs are versatile protein domains that can be used to mark neural systems and treat a range of disorders in neural systems.
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Affiliation(s)
- Hye Rin Kim
- Department of Integrative Biotechnology, Sungkyunkwan University, Seoburo 2066, Suwon, Gyeonggi, 16419, Republic of Korea
| | - Younghun Jung
- Department of Integrative Biotechnology, Sungkyunkwan University, Seoburo 2066, Suwon, Gyeonggi, 16419, Republic of Korea.,Institute of Biomolecule Control, Sungkyunkwan University, Seoburo 2066, Suwon, Gyeonggi, 16419, Republic of Korea
| | - Jonghyeok Shin
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Myungseo Park
- Environmental Health Sciences, School of Public Health, University of Minnesota, Saint Paul, MN, 55108, USA
| | - Dae-Hyuk Kweon
- Department of Integrative Biotechnology, Sungkyunkwan University, Seoburo 2066, Suwon, Gyeonggi, 16419, Republic of Korea. .,Institute of Biomolecule Control, Sungkyunkwan University, Seoburo 2066, Suwon, Gyeonggi, 16419, Republic of Korea. .,Biologics Research Center, Sungkyunkwan University, Seoburo 2066, Suwon, Gyeonggi, 16419, Republic of Korea. .,Interdisciplinary Program in BioCosmetics, Sungkyunkwan University, Seoburo 2066, Suwon, Gyeonggi, 16419, Republic of Korea.
| | - Choongjin Ban
- Department of Environmental Horticulture, University of Seoul, 163 Seoulsiripdaero, Dongdaemun-gu, Seoul, 02504, Republic of Korea.
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5
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Takeuchi T, Okuno T, Miyashiro A, Kohda T, Miyamoto R, Izumi Y, Kozaki S, Kaji R. Clinical Safety and Tolerability of A2NTX, a Novel Low-Molecular-Weight Neurotoxin Derived from Botulinum Neurotoxin Subtype A2, in Comparison with Subtype A1 Toxins. Toxins (Basel) 2021; 13:824. [PMID: 34822610 PMCID: PMC8623066 DOI: 10.3390/toxins13110824] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 11/11/2021] [Accepted: 11/16/2021] [Indexed: 11/29/2022] Open
Abstract
All the botulinum type A neurotoxins available for clinical use are of the A1 subtype. We developed a subtype A2 low-molecular-weight (150 kD (kilo Dalton)) neurotoxin (A2NTX) with less spread and faster entry into the motor nerve terminal than A1 in vitro and in vivo. Preliminary clinical studies showed that its efficacy is superior to A1 toxins. We conducted an open study exploring its safety and tolerability profile in comparison with A1LL (LL type A1 toxin, or onabotulinumtoxinA) and a low-molecular-weight (150 kD) A1 neurotoxin (A1NTX). Those who had been using A1LL (n = 90; 50-360 mouse LD50 units) or A1NTX (n = 30; 50-580 units) were switched to A2NTX (n = 120; 25-600 units) from 2010 to 2018 (number of sessions ~27, cumulative doses ~11,640 units per patient). The adverse events for A2NTX included weakness (n = 1, ascribed to alcoholic polyneuropathy), dysphagia (1), local weakness (4), and spread to other muscles (1), whereas those for A1LL or A1NTX comprised weakness (n = 2, A1NTX), dysphagia (8), ptosis (6), local weakness (7), and spread to other muscles (15). After injections, 89 out of 120 patients preferred A2NTX to A1 for the successive sessions. The present study demonstrated that A2NTX had clinical safety up to the dose of 500 units and was well tolerated compared to A1 toxins.
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Affiliation(s)
- Toshiaki Takeuchi
- Department of Clinical Neuroscience, Graduate School of Medicine, Tokushima University, Tokushima 770-8503, Japan; (T.T.); (T.O.); (A.M.); (R.M.); (Y.I.)
| | - Tsuyoshi Okuno
- Department of Clinical Neuroscience, Graduate School of Medicine, Tokushima University, Tokushima 770-8503, Japan; (T.T.); (T.O.); (A.M.); (R.M.); (Y.I.)
| | - Ai Miyashiro
- Department of Clinical Neuroscience, Graduate School of Medicine, Tokushima University, Tokushima 770-8503, Japan; (T.T.); (T.O.); (A.M.); (R.M.); (Y.I.)
| | - Tomoko Kohda
- Department of Veterinary Sciences, School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan; (T.K.); (S.K.)
| | - Ryosuke Miyamoto
- Department of Clinical Neuroscience, Graduate School of Medicine, Tokushima University, Tokushima 770-8503, Japan; (T.T.); (T.O.); (A.M.); (R.M.); (Y.I.)
| | - Yuishin Izumi
- Department of Clinical Neuroscience, Graduate School of Medicine, Tokushima University, Tokushima 770-8503, Japan; (T.T.); (T.O.); (A.M.); (R.M.); (Y.I.)
| | - Shunji Kozaki
- Department of Veterinary Sciences, School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan; (T.K.); (S.K.)
| | - Ryuji Kaji
- Department of Clinical Neuroscience, Graduate School of Medicine, Tokushima University, Tokushima 770-8503, Japan; (T.T.); (T.O.); (A.M.); (R.M.); (Y.I.)
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6
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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.
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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
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8
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Kohda T, Tsukamoto K, Torii Y, Kozaki S, Mukamoto M. Translocation domain of botulinum neurotoxin A subtype 2 potently induces entry into neuronal cells. Microbiol Immunol 2020; 64:502-511. [PMID: 32301520 DOI: 10.1111/1348-0421.12796] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 04/10/2020] [Accepted: 04/14/2020] [Indexed: 11/27/2022]
Abstract
Botulinum neurotoxin (BoNT) is the causative agent of botulism in humans and animals. Only BoNT serotype A subtype 1 (BoNT/A1) is used clinically because of its high potency and long duration of action. BoNT/A1 and BoNT/A subtype 2 (BoNT/A2) have a high degree of amino acid sequence similarity in the light chain (LC) (96%), whereas their N-and C-terminal heavy chain (HN and HC ) differ by 13%. The LC acts as a zinc-dependent endopeptidase, HN as the translocation domain, and HC as the receptor-binding domain. BoNT/A2 and BoNT/A1 had similar potency in the mouse bioassay, but BoNT/A2 entered faster and more efficiently into neuronal cells. To identify the domains responsible for these characteristics, HN of BoNT/A1 and BoNT/A2 was exchanged to construct chimeric BoNT/A121 and BoNT/A212. After expression in Escherichia coli, chimeric and wild-type BoNT/As were purified as single-chain proteins and activated by conversion to disulfide-linked dichains. The toxicities of recombinant wild-type and chimeric BoNT/As were similar, but dropped to 60% compared with the values of native BoNT/As. The relative orders of SNAP-25 cleavage activity in neuronal cells and toxicity differed. BoNT/A121 and recombinant BoNT/A2 have similar SNAP-25 cleavage activity. BoNT/A2 HN is possibly responsible for the higher potency of BoNT/A2 than BoNT/A1.
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Affiliation(s)
- Tomoko Kohda
- Department of Veterinary Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Izumisano, Osaka, Japan
| | - Kentaro Tsukamoto
- Department of Microbiology, Fujita Health University School of Medicine, Toyoake, Aichi, Japan
| | - Yasushi Torii
- Department of Animal Science, Tokyo University of Agriculture, Atsugi, Kanagawa, Japan
| | - Shunji Kozaki
- Department of Veterinary Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Izumisano, Osaka, Japan
| | - Masafumi Mukamoto
- Department of Veterinary Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Izumisano, Osaka, Japan
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9
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Gregory KS, Liu SM, Acharya KR. Crystal structure of botulinum neurotoxin subtype A3 cell binding domain in complex with GD1a co-receptor ganglioside. FEBS Open Bio 2020; 10:298-305. [PMID: 31945264 PMCID: PMC7050238 DOI: 10.1002/2211-5463.12790] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 01/07/2020] [Accepted: 01/10/2020] [Indexed: 01/20/2023] Open
Abstract
Botulinum neurotoxins (BoNTs) are one of the most toxic proteins known to humans. Their molecular structure is comprised of three essential domains—a cell binding domain (HC), translocation domain and catalytic domain (light chain) . The HC domain facilitates the highly specific binding of BoNTs to the neuronal membrane via a dual‐receptor complex involving a protein receptor and a ganglioside. Variation in activity/toxicity across subtypes of serotype A has been attributed to changes in protein and ganglioside interactions, and their implications are important in the design of novel BoNT‐based therapeutics. Here, we present the structure of BoNT/A3 cell binding domain (HC/A3) in complex with the ganglioside GD1a at 1.75 Å resolution. The structure revealed that six residues interact with the three outermost monosaccharides of GD1a through several key hydrogen bonding interactions. A detailed comparison of structures of HC/A3 with HC/A1 revealed subtle conformational differences at the ganglioside binding site upon carbohydrate binding.
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Affiliation(s)
- Kyle S Gregory
- Department of Biology and Biochemistry, Claverton Down, University of Bath, UK
| | | | - K Ravi Acharya
- Department of Biology and Biochemistry, Claverton Down, University of Bath, UK
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10
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Pellett S, Tepp WH, Johnson EA. Critical Analysis of Neuronal Cell and the Mouse Bioassay for Detection of Botulinum Neurotoxins. Toxins (Basel) 2019; 11:toxins11120713. [PMID: 31817843 PMCID: PMC6950160 DOI: 10.3390/toxins11120713] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 11/12/2019] [Accepted: 11/22/2019] [Indexed: 12/14/2022] Open
Abstract
Botulinum Neurotoxins (BoNTs) are a large protein family that includes the most potent neurotoxins known to humankind. BoNTs delivered locally in humans at low doses are widely used pharmaceuticals. Reliable and quantitative detection of BoNTs is of paramount importance for the clinical diagnosis of botulism, basic research, drug development, potency determination, and detection in clinical, environmental, and food samples. Ideally, a definitive assay for BoNT should reflect the activity of each of the four steps in nerve intoxication. The in vivo mouse bioassay (MBA) is the ‘gold standard’ for the detection of BoNTs. The MBA is sensitive, robust, semi-quantitative, and reliable within its sensitivity limits. Potential drawbacks with the MBA include assay-to-assay potency variations, especially between laboratories, and false positives or negatives. These limitations can be largely avoided by careful planning and performance. Another detection method that has gained importance in recent years for research and potency determination of pharmaceutical BoNTs is cell-based assays, as these assays can be highly sensitive, quantitative, human-specific, and detect fully functional holotoxins at physiologically relevant concentrations. A myriad of other in vitro BoNT detection methods exist. This review focuses on critical factors and assay limitations of the mouse bioassay and cell-based assays for BoNT detection.
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11
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Structural insights into the interaction of botulinum neurotoxin a with its neuronal receptor SV2C. Toxicon 2019; 175:36-43. [PMID: 31783045 DOI: 10.1016/j.toxicon.2019.11.010] [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: 08/16/2019] [Revised: 11/08/2019] [Accepted: 11/25/2019] [Indexed: 11/23/2022]
Abstract
A dual-receptor interaction with a polysialoganglioside and synaptic vesicle glycoprotein 2 (SV2) is required for botulinum neurotoxin A (BoNT) toxicity. Here, we review what is currently known about the BoNT/A-SV2 interaction based on structural studies. Currently, five crystal structures of the receptor-binding domain (Hc) of BoNT subtypes A1 and A2 complexed to the large luminal domain (LD4) of SV2C have been determined. On the basis of the available structures, we will discuss the importance of protein-protein and protein-carbohydrate interactions for BoNT/A toxicity as well as the high plasticity of BoNT/A for receptor recognition by tolerating a variety of side-chain interactions at the interface. A plausible explanation how receptor-binding specificity of BoNT/A may be achieved without an extensive and conserved side chain-side chain interaction network will be provided.
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12
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Moritz MS, Tepp WH, Inzalaco HN, Johnson EA, Pellett S. Comparative functional analysis of mice after local injection with botulinum neurotoxin A1, A2, A6, and B1 by catwalk analysis. Toxicon 2019; 167:20-28. [PMID: 31181297 PMCID: PMC6688953 DOI: 10.1016/j.toxicon.2019.06.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 05/20/2019] [Accepted: 06/03/2019] [Indexed: 01/10/2023]
Abstract
Botulinum neurotoxins (BoNTs) are potent neurotoxins and are the causative agent of botulism, as well as valuable pharmaceuticals. BoNTs are divided into seven serotypes that comprise over 40 reported subtypes. BoNT/A1 and BoNT/B1 are currently the only subtypes approved for pharmaceutical use in the USA. While several other BoNT subtypes including BoNT/A2 and/A6 have been proposed as promising pharmaceuticals, detailed characterization using in vivo assays are essential to determine their pharmaceutical characteristics compared to the currently used BoNT/A1 and/B1. Several methods for studying BoNTs in mice are being used, but no objective and quantitative assay for assessment of functional outcomes after injection has been described. Here we describe the use of CatWalk XT as a new analytical tool for the objective and quantitative analysis of the paralytic effect after local intramuscular injection of BoNT subtypes A1, A2, A6, and B1. Catwalk is a sophisticated gait and locomotion analysis system that quantitatively analyzes a rodent's paw print dimensions and footfall patterns while traversing a glass plate during unforced walk. Significant changes were observed in several gait parameters in mice after local intramuscular injection of all tested BoNT subtypes, however, no changes were observed in mice injected intraperitoneally with the same BoNTs. While a clear difference in time to peak paralysis was observed between BoNT/A1 and/B1, injection of all four toxins resulted in a deficit in the injected limb with the other limbs functionally compensating and with no qualitative differences between the four BoNT subtypes. The presented data demonstrate the utility of CatWalk as a tool for functional outcomes after local BoNT injection through its ability to collect large amounts of quantitative data and objectively analyze sensitive changes in static and dynamic gait parameters.
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Affiliation(s)
- Molly S Moritz
- University of Wisconsin-Madison, Dept. of Bacteriology, USA
| | - William H Tepp
- University of Wisconsin-Madison, Dept. of Bacteriology, USA
| | | | - Eric A Johnson
- University of Wisconsin-Madison, Dept. of Bacteriology, USA
| | - Sabine Pellett
- University of Wisconsin-Madison, Dept. of Bacteriology, USA.
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Davies JR, Liu SM, Acharya KR. Variations in the Botulinum Neurotoxin Binding Domain and the Potential for Novel Therapeutics. Toxins (Basel) 2018; 10:toxins10100421. [PMID: 30347838 PMCID: PMC6215321 DOI: 10.3390/toxins10100421] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 10/11/2018] [Accepted: 10/18/2018] [Indexed: 01/23/2023] Open
Abstract
Botulinum neurotoxins (BoNTs) are categorised into immunologically distinct serotypes BoNT/A to /G). Each serotype can also be further divided into subtypes based on differences in amino acid sequence. BoNTs are ~150 kDa proteins comprised of three major functional domains: an N-terminal zinc metalloprotease light chain (LC), a translocation domain (HN), and a binding domain (HC). The HC is responsible for targeting the BoNT to the neuronal cell membrane, and each serotype has evolved to bind via different mechanisms to different target receptors. Most structural characterisations to date have focussed on the first identified subtype within each serotype (e.g., BoNT/A1). Subtype differences within BoNT serotypes can affect intoxication, displaying different botulism symptoms in vivo, and less emphasis has been placed on investigating these variants. This review outlines the receptors for each BoNT serotype and describes the basis for the highly specific targeting of neuronal cell membranes. Understanding receptor binding is of vital importance, not only for the generation of novel therapeutics but also for understanding how best to protect from intoxication.
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Affiliation(s)
- Jonathan R Davies
- Department of Biology and Biochemistry, University of Bath, Bath BA2 7AY, UK.
| | - Sai Man Liu
- Ipsen Bioinnovation Limited, Abingdon OX14 4RY, UK.
| | - K Ravi Acharya
- Department of Biology and Biochemistry, University of Bath, Bath BA2 7AY, UK.
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14
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Variability of Botulinum Toxins: Challenges and Opportunities for the Future. Toxins (Basel) 2018; 10:toxins10090374. [PMID: 30217070 PMCID: PMC6162648 DOI: 10.3390/toxins10090374] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 09/03/2018] [Accepted: 09/08/2018] [Indexed: 12/31/2022] Open
Abstract
Botulinum neurotoxins (BoNTs) are the most potent known toxins, and are therefore classified as extremely harmful biological weapons. However, BoNTs are therapeutic drugs that are widely used and have an increasing number of applications. BoNTs show a high diversity and are divided into multiple types and subtypes. Better understanding of the activity at the molecular and clinical levels of the natural BoNT variants as well as the development of BoNT-based chimeric molecules opens the door to novel medical applications such as silencing the sensory neurons at targeted areas and dermal restoration. This short review is focused on BoNTs’ variability and the opportunities or challenges posed for future clinical applications.
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15
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Antipova V, Wree A, Holzmann C, Mann T, Palomero-Gallagher N, Zilles K, Schmitt O, Hawlitschka A. Unilateral Botulinum Neurotoxin-A Injection into the Striatum of C57BL/6 Mice Leads to a Different Motor Behavior Compared with Rats. Toxins (Basel) 2018; 10:E295. [PMID: 30018211 PMCID: PMC6070800 DOI: 10.3390/toxins10070295] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 07/13/2018] [Accepted: 07/15/2018] [Indexed: 12/26/2022] Open
Abstract
Different morphological changes in the caudate-putamen (CPu) of naïve rats and mice were observed after intrastriatal botulinum neurotoxin-A (BoNT-A) injection. For this purpose we here studied various motor behaviors in mice (n = 46) longitudinally up to 9 months after intrastriatal BoNT-A administration as previously reported for rats, and compared both outcomes. Apomorphine- and amphetamine-induced rotational behavior, spontaneous motor behavior, as well as lateralized neglect were studied in mice after the injection of single doses of BoNT-A into the right CPu, comparing them with sham-injected animals. Unilateral intrastriatal injection of BoNT-A in mice induced significantly increased contralateral apomorphine-induced rotations for 1 to 3 months, as well as significantly increased contralateral amphetamine-induced rotations 1 to 9 months after injection. In rats (n = 28), unilateral BoNT-A injection also induced significantly increased contralateral apomorphine-induced rotations 3 months after injection, but did not provoke amphetamine-induced rotations at all. Lateralized sensorimotor integration, forelimb preference, and forelimb stepping were significantly impaired on the left side. The differences in motor behaviors between rats and mice may be caused by different BoNT-A effects on cholinergic and catecholaminergic fibers in rat and mouse striata, interspecies differences in striatal receptor densities, and different connectomes of the basal ganglia.
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Affiliation(s)
- Veronica Antipova
- Institute of Anatomy, Rostock University Medical Center, Gertrudenstrasse 9, D-18057 Rostock, Germany.
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Macroscopic and Clinical Anatomy, Medical University of Graz, Harrachgasse 21/1, A-8010 Graz, Austria.
| | - Andreas Wree
- Institute of Anatomy, Rostock University Medical Center, Gertrudenstrasse 9, D-18057 Rostock, Germany.
| | - Carsten Holzmann
- Institute of Medical Genetics, Rostock University Medical Center, Ernst-Heydemann-Strasse 8, D-18057 Rostock, Germany.
| | - Teresa Mann
- Institute of Anatomy, Rostock University Medical Center, Gertrudenstrasse 9, D-18057 Rostock, Germany.
| | - Nicola Palomero-Gallagher
- Institute of Neuroscience and Medicine INM-1, Research Center Jülich, D-52425 Jülich, Germany.
- Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH Aachen, D-52062 Aachen, Germany.
| | - Karl Zilles
- Institute of Neuroscience and Medicine INM-1, Research Center Jülich, D-52425 Jülich, Germany.
- Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH Aachen, D-52062 Aachen, Germany.
- JARA-Translational Brain Medicine, D-52062 Aachen, Germany.
| | - Oliver Schmitt
- Institute of Anatomy, Rostock University Medical Center, Gertrudenstrasse 9, D-18057 Rostock, Germany.
| | - Alexander Hawlitschka
- Institute of Anatomy, Rostock University Medical Center, Gertrudenstrasse 9, D-18057 Rostock, Germany.
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16
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Fonfria E, Maignel J, Lezmi S, Martin V, Splevins A, Shubber S, Kalinichev M, Foster K, Picaut P, Krupp J. The Expanding Therapeutic Utility of Botulinum Neurotoxins. Toxins (Basel) 2018; 10:E208. [PMID: 29783676 PMCID: PMC5983264 DOI: 10.3390/toxins10050208] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 05/15/2018] [Accepted: 05/16/2018] [Indexed: 12/11/2022] Open
Abstract
Botulinum neurotoxin (BoNT) is a major therapeutic agent that is licensed in neurological indications, such as dystonia and spasticity. The BoNT family, which is produced in nature by clostridial bacteria, comprises several pharmacologically distinct proteins with distinct properties. In this review, we present an overview of the current therapeutic landscape and explore the diversity of BoNT proteins as future therapeutics. In recent years, novel indications have emerged in the fields of pain, migraine, overactive bladder, osteoarthritis, and wound healing. The study of biological effects distal to the injection site could provide future opportunities for disease-tailored BoNT therapies. However, there are some challenges in the pharmaceutical development of BoNTs, such as liquid and slow-release BoNT formulations; and, transdermal, transurothelial, and transepithelial delivery. Innovative approaches in the areas of formulation and delivery, together with highly sensitive analytical tools, will be key for the success of next generation BoNT clinical products.
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Affiliation(s)
- Elena Fonfria
- Ipsen Bioinnovation, 102 Park Drive, Milton Park, Abingdon, Oxfordshire OX14 4RY, UK.
| | - Jacquie Maignel
- Ipsen Innovation, 5 Avenue du Canada, 91940 Les Ulis, France.
| | - Stephane Lezmi
- Ipsen Innovation, 5 Avenue du Canada, 91940 Les Ulis, France.
| | - Vincent Martin
- Ipsen Innovation, 5 Avenue du Canada, 91940 Les Ulis, France.
| | - Andrew Splevins
- Ipsen Bioinnovation, 102 Park Drive, Milton Park, Abingdon, Oxfordshire OX14 4RY, UK.
| | - Saif Shubber
- Ipsen Biopharm Ltd., Wrexham Industrial Estate, 9 Ash Road, Wrexham LL13 9UF, UK.
| | | | - Keith Foster
- Ipsen Bioinnovation, 102 Park Drive, Milton Park, Abingdon, Oxfordshire OX14 4RY, UK.
| | - Philippe Picaut
- Ipsen Bioscience, 650 Kendall Street, Cambridge, MA 02142, USA.
| | - Johannes Krupp
- Ipsen Innovation, 5 Avenue du Canada, 91940 Les Ulis, France.
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17
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Hawlitschka A, Wree A. Experimental Intrastriatal Applications of Botulinum Neurotoxin-A: A Review. Int J Mol Sci 2018; 19:ijms19051392. [PMID: 29735936 PMCID: PMC5983629 DOI: 10.3390/ijms19051392] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 05/01/2018] [Accepted: 05/02/2018] [Indexed: 11/16/2022] Open
Abstract
Parkinson’s disease (PD) is one of the most frequent neurodegenerative disorders. Its main pathophysiological characteristic is the loss of dopaminergic neurons in the substantia nigra pars compacta followed by a lack of striatal dopaminergic input and a consequent disinhibition of tonically active cholinergic interneurons. The resulting striatal hypercholinism causes major motor symptoms in PD. Anticholinergic pharmacotherapies have antiparkinsonian effects on motor symptoms, but, due to systemic actions, also numerous severe side effects occur on a regular basis. To circumvent these side effects, a local anticholinergic therapy acting exclusively in the striatum would be reasonable. Botulinum neurotoxin-A (BoNT-A) is synthesized by Clostridium botulinum and blocks the release of acetylcholine from the presynaptic bouton. For several decades, BoNT-A has been used successfully for medical and cosmetic purposes to induce controlled paralyses of single muscles. Our group and others investigated the experimental treatment of striatal hypercholinism by the direct injection of BoNT-A into the striatum of rats and mice as well as of hemiparkinsonian animal models. This review gives an overview of the most important results of the experimental intrastriatal BoNT-A application, with a focus on hemiparkinsonian rats.
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Affiliation(s)
- Alexander Hawlitschka
- Institute of Anatomy, Rostock University Medical Center, Gertrudenstraße 9, 18057 Rostock, Germany.
| | - Andreas Wree
- Institute of Anatomy, Rostock University Medical Center, Gertrudenstraße 9, 18057 Rostock, Germany.
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18
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Caleo M, Restani L. Exploiting Botulinum Neurotoxins for the Study of Brain Physiology and Pathology. Toxins (Basel) 2018; 10:toxins10050175. [PMID: 29693600 PMCID: PMC5983231 DOI: 10.3390/toxins10050175] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Revised: 04/21/2018] [Accepted: 04/23/2018] [Indexed: 01/25/2023] Open
Abstract
Botulinum neurotoxins are metalloproteases that specifically cleave N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins in synaptic terminals, resulting in a potent inhibition of vesicle fusion and transmitter release. The family comprises different serotypes (BoNT/A to BoNT/G). The natural target of these toxins is represented by the neuromuscular junction, where BoNTs block acetylcholine release. In this review, we describe the actions of botulinum toxins after direct delivery to the central nervous system (CNS), where BoNTs block exocytosis of several transmitters, with near-complete silencing of neural networks. The use of clostridial neurotoxins in the CNS has allowed us to investigate specifically the role of synaptic activity in different physiological and pathological processes. The silencing properties of BoNTs can be exploited for therapeutic purposes, for example to counteract pathological hyperactivity and seizures in epileptogenic brain foci, or to investigate the role of activity in degenerative diseases like prion disease. Altogether, clostridial neurotoxins and their derivatives hold promise as powerful tools for both the basic understanding of brain function and the dissection and treatment of activity-dependent pathogenic pathways.
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Affiliation(s)
- Matteo Caleo
- CNR Neuroscience Institute, via G. Moruzzi 1, 56124 Pisa, Italy.
| | - Laura Restani
- CNR Neuroscience Institute, via G. Moruzzi 1, 56124 Pisa, Italy.
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Zuverink M, Barbieri JT. Protein Toxins That Utilize Gangliosides as Host Receptors. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2018; 156:325-354. [PMID: 29747819 DOI: 10.1016/bs.pmbts.2017.11.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Subsets of protein toxins utilize gangliosides as host receptors. Gangliosides are preferred receptors due to their extracellular localization on the eukaryotic cell and due to their essential nature in host physiology. Glycosphingolipids, including gangliosides, are mediators of signal transduction within and between eukaryotic cells. Protein toxins possess AB structure-function organization, where the A domain encodes a catalytic function for the posttranslational modification of a host macromolecule, including proteins and nucleic acids, and a B domain, which encodes host receptor recognition, including proteins and glycosphingolipids, alone or in combination. Protein toxins use similar strategies to bind glycans by pockets and loops, generally employing hydrogen bonding and aromatic stacking to stabilize interactions with sugars. In some cases, glycan binding facilitates uptake, while in other cases, cross-linking or a second receptor is necessary to stimulate entry. The affinity that protein toxins have for host glycans is necessary for tissue targeting, but not always sufficient to cause disease. In addition to affinity for binding the glycan, the lipid moiety also plays an important role in productive uptake and tissue tropism. Upon endocytosis, the protein toxin must escape to another intracellular compartment or into cytosol to modify a host substrate, modulating host signaling, often resulting in cytotoxic or apoptotic events in the cell, and a unique morbidity for the organism. The study of protein toxins that utilize gangliosides as host receptors has illuminated numerous eukaryotic cellular processes, identified the basis for developing interventions to prevent disease through vaccines and control bacterial diseases through therapies. In addition, subsets of these protein toxins have been utilized as therapeutic agents to treat numerous human inflictions.
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20
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Feng Y, Liu W, Pan L, Jiang C, Zhang C, Lu Y, Nie Z, Jin L. Comparison of neurotoxic potency between a novel chinbotulinumtoxinA with onabotulinumtoxinA, incobotulinumtoxinA and lanbotulinumtoxinA in rats. DRUG DESIGN DEVELOPMENT AND THERAPY 2017; 11:1927-1939. [PMID: 28721012 PMCID: PMC5500563 DOI: 10.2147/dddt.s138489] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Four botulinumtoxin type A (BoNT/A) products, onabotulinumtoxinA (A/Ona), incobotulinumtoxinA (A/Inco), lanbotulinumtoxinA (A/Lan) and chinbotulinumtoxinA (A/Chin), are applied in the present study, among which A/Chin is newly produced. We aimed to compare the neurotoxic potency of these toxins by the gauge of muscle strength reduction. Furthermore, potential molecular and cellular mechanisms were also explored. According to our data, muscle strengths in the four toxin groups were all significantly decreased after injection for 1 week. A/Chin achieved the most obvious reduction in muscle strength as compared to the other three products at the dose of 0.5 U. However, there was no difference between the four toxins when increased to 2 U. As the toxins wore off, muscle strength recovered to basal level 12 weeks postinjection. We further measured the expression levels of key factors involved in neuromuscular junction stabilization and muscle genesis. Our results showed that nicotinic acetylcholine receptor, myogenic regulatory factors and muscle-specific receptor tyrosine kinase were all significantly upregulated upon BoNT/A treatment. Consistent with the result of muscle strength, A/Chin had the most obvious induction of gene expression. Moreover, we also found local inflammation response following BoNT/A injection. Owing to lack of complexing proteins, both A/Inco and A/Chin stimulated relatively lighter inflammation compared to that of A/Ona and A/Lan groups. In conclusion, our study provided evidence for the efficacy of the novel A/Chin and its similar functional mode to that of A/Ona, A/Inco and A/Lan. In addition, A/Chin has superiority in inducing muscle paralysis and inflammation stimulation, which may indicate faster onset and longer duration of this novel A/Chin.
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Affiliation(s)
- Ya Feng
- Department of Neurology, Shanghai Tongji Hospital, Tongji University School of Medicine, Shanghai, People's Republic of China
| | - Wuchao Liu
- Department of Neurology, Shanghai Tongji Hospital, Tongji University School of Medicine, Shanghai, People's Republic of China
| | - Lizhen Pan
- Department of Neurology, Shanghai Tongji Hospital, Tongji University School of Medicine, Shanghai, People's Republic of China
| | - Cong Jiang
- Department of Neurology, Shanghai Tongji Hospital, Tongji University School of Medicine, Shanghai, People's Republic of China
| | - Chengxi Zhang
- Department of Neurology, Shanghai Tongji Hospital, Tongji University School of Medicine, Shanghai, People's Republic of China
| | - Yuxuan Lu
- Department of Neurology, Shanghai Tongji Hospital, Tongji University School of Medicine, Shanghai, People's Republic of China
| | - Zhiyu Nie
- Department of Neurology, Shanghai Tongji Hospital, Tongji University School of Medicine, Shanghai, People's Republic of China
| | - Lingjing Jin
- Department of Neurology, Shanghai Tongji Hospital, Tongji University School of Medicine, Shanghai, People's Republic of China
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21
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Burns JR, Lambert GS, Baldwin MR. Insights into the Mechanisms by Which Clostridial Neurotoxins Discriminate between Gangliosides. Biochemistry 2017; 56:2571-2583. [DOI: 10.1021/acs.biochem.6b01246] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Joshua R. Burns
- Department of Molecular Microbiology
and Immunology, University of Missouri School of Medicine, Columbia, Missouri 65212, United States
| | - Gregory S. Lambert
- Department of Molecular Microbiology
and Immunology, University of Missouri School of Medicine, Columbia, Missouri 65212, United States
| | - Michael R. Baldwin
- Department of Molecular Microbiology
and Immunology, University of Missouri School of Medicine, Columbia, Missouri 65212, United States
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22
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Benoit RM, Schärer MA, Wieser MM, Li X, Frey D, Kammerer RA. Crystal structure of the BoNT/A2 receptor-binding domain in complex with the luminal domain of its neuronal receptor SV2C. Sci Rep 2017; 7:43588. [PMID: 28252640 PMCID: PMC5333631 DOI: 10.1038/srep43588] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 01/25/2017] [Indexed: 11/09/2022] Open
Abstract
A detailed molecular understanding of botulinum neurotoxin (BoNT)/host-cell-receptor interactions is fundamental both for developing strategies against botulism and for generating improved BoNT variants for medical applications. The X-ray crystal structure of the receptor-binding domain (HC) of BoNT/A1 in complex with the luminal domain (LD) of its neuronal receptor SV2C revealed only few specific side-chain - side-chain interactions that are important for binding. Notably, two BoNT/A1 residues, Arg 1156 and Arg 1294, that are crucial for the interaction with SV2, are not conserved among subtypes. Because it has been suggested that differential receptor binding of subtypes might explain their differences in biological activity, we determined the crystal structure of BoNT/A2-HC in complex with SV2C-LD. Although only few side-chain interactions are conserved between the two BoNT/A subtypes, the overall binding mode of subtypes A1 and A2 is virtually identical. In the BoNT/A2-HC - SV2C complex structure, a missing cation-π stacking is compensated for by an additional salt bridge and an anion-π stacking interaction, which explains why the binding of BoNT/A subtypes to SV2C tolerates variable side chains. These findings suggest that motif extensions and a shallow binding cleft in BoNT/A-HC contribute to binding specificity.
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Affiliation(s)
- Roger M Benoit
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - Martin A Schärer
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - Mara M Wieser
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - Xiaodan Li
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - Daniel Frey
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - Richard A Kammerer
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
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