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Li M, Mao K, Huang M, Liao Y, Fu J, Pan K, Shi Q, Gao B. Venomics Reveals the Venom Complexity of Sea Anemone Heteractis magnifica. Mar Drugs 2024; 22:71. [PMID: 38393042 PMCID: PMC10890322 DOI: 10.3390/md22020071] [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: 12/19/2023] [Revised: 01/26/2024] [Accepted: 01/27/2024] [Indexed: 02/25/2024] Open
Abstract
The venoms of various sea anemones are rich in diverse toxins, which usually play a dual role in capturing prey and deterring predators. However, the complex components of such venoms have not been well known yet. Here, venomics of integrating transcriptomic and proteomic technologies was applied for the first time to identify putative protein and peptide toxins from different tissues of the representative sea anemone, Heteractis magnifica. The transcriptomic analysis of H. magnifica identified 728 putative toxin sequences, including 442 and 381 from the tentacles and the column, respectively, and they were assigned to 68 gene superfamilies. The proteomic analysis confirmed 101 protein and peptide toxins in the venom, including 91 in the tentacles and 39 in the column. The integrated venomics also confirmed that some toxins such as the ShK-like peptides and defensins are co-expressed in both the tentacles and the column. Meanwhile, a homology analysis was conducted to predict the three-dimensional structures and potential activity of seven representative toxins. Altogether, this venomics study revealed the venom complexity of H. magnifica, which will help deepen our understanding of cnidarian toxins, thereby supporting the in-depth development of valuable marine drugs.
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Affiliation(s)
- Ming Li
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, Hainan Key Laboratory for Research and Development of Tropical Herbs, School of Pharmacy, Hainan Medical University, Haikou 571199, China; (M.L.); (K.M.); (M.H.); (Y.L.); (J.F.); (K.P.)
| | - Kailin Mao
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, Hainan Key Laboratory for Research and Development of Tropical Herbs, School of Pharmacy, Hainan Medical University, Haikou 571199, China; (M.L.); (K.M.); (M.H.); (Y.L.); (J.F.); (K.P.)
| | - Meiling Huang
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, Hainan Key Laboratory for Research and Development of Tropical Herbs, School of Pharmacy, Hainan Medical University, Haikou 571199, China; (M.L.); (K.M.); (M.H.); (Y.L.); (J.F.); (K.P.)
| | - Yanling Liao
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, Hainan Key Laboratory for Research and Development of Tropical Herbs, School of Pharmacy, Hainan Medical University, Haikou 571199, China; (M.L.); (K.M.); (M.H.); (Y.L.); (J.F.); (K.P.)
| | - Jinxing Fu
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, Hainan Key Laboratory for Research and Development of Tropical Herbs, School of Pharmacy, Hainan Medical University, Haikou 571199, China; (M.L.); (K.M.); (M.H.); (Y.L.); (J.F.); (K.P.)
| | - Kun Pan
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, Hainan Key Laboratory for Research and Development of Tropical Herbs, School of Pharmacy, Hainan Medical University, Haikou 571199, China; (M.L.); (K.M.); (M.H.); (Y.L.); (J.F.); (K.P.)
| | - Qiong Shi
- Laboratory of Aquatic Genomics, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518057, China
- Shenzhen Key Laboratory of Marine Genomics, Guangdong Provincial Key Laboratory of Molecular Breeding in Marine Economic Animals, BGI Academy of Marine Sciences, BGI Marine, Shenzhen 518081, China
| | - Bingmiao Gao
- Key Laboratory of Tropical Translational Medicine of Ministry of Education, Hainan Key Laboratory for Research and Development of Tropical Herbs, School of Pharmacy, Hainan Medical University, Haikou 571199, China; (M.L.); (K.M.); (M.H.); (Y.L.); (J.F.); (K.P.)
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Monastyrnaya MM, Kalina RS, Kozlovskaya EP. The Sea Anemone Neurotoxins Modulating Sodium Channels: An Insight at Structure and Functional Activity after Four Decades of Investigation. Toxins (Basel) 2022; 15:toxins15010008. [PMID: 36668828 PMCID: PMC9863223 DOI: 10.3390/toxins15010008] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 12/13/2022] [Accepted: 12/15/2022] [Indexed: 12/24/2022] Open
Abstract
Many human cardiovascular and neurological disorders (such as ischemia, epileptic seizures, traumatic brain injury, neuropathic pain, etc.) are associated with the abnormal functional activity of voltage-gated sodium channels (VGSCs/NaVs). Many natural toxins, including the sea anemone toxins (called neurotoxins), are an indispensable and promising tool in pharmacological researches. They have widely been carried out over the past three decades, in particular, in establishing different NaV subtypes functional properties and a specific role in various pathologies. Therefore, a large number of publications are currently dedicated to the search and study of the structure-functional relationships of new sea anemone natural neurotoxins-potential pharmacologically active compounds that specifically interact with various subtypes of voltage gated sodium channels as drug discovery targets. This review presents and summarizes some updated data on the structure-functional relationships of known sea anemone neurotoxins belonging to four structural types. The review also emphasizes the study of type 2 neurotoxins, produced by the tropical sea anemone Heteractis crispa, five structurally homologous and one unique double-stranded peptide that, due to the absence of a functionally significant Arg14 residue, loses toxicity but retains the ability to modulate several VGSCs subtypes.
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Kalina RS, Peigneur S, Zelepuga EA, Dmitrenok PS, Kvetkina AN, Kim NY, Leychenko EV, Tytgat J, Kozlovskaya EP, Monastyrnaya MM, Gladkikh IN. New Insights into the Type II Toxins from the Sea Anemone Heteractis crispa. Toxins (Basel) 2020; 12:E44. [PMID: 31936885 PMCID: PMC7020476 DOI: 10.3390/toxins12010044] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 01/07/2020] [Accepted: 01/08/2020] [Indexed: 12/23/2022] Open
Abstract
Toxins modulating NaV channels are the most abundant and studied peptide components of sea anemone venom. Three type-II toxins, δ-SHTX-Hcr1f (= RpII), RTX-III, and RTX-VI, were isolated from the sea anemone Heteractis crispa. RTX-VI has been found to be an unusual analog of RTX-III. The electrophysiological effects of Heteractis toxins on nine NaV subtypes were investigated for the first time. Heteractis toxins mainly affect the inactivation of the mammalian NaV channels expressed in the central nervous system (NaV1.1-NaV1.3, NaV1.6) as well as insect and arachnid channels (BgNaV1, VdNaV1). The absence of Arg13 in the RTX-VI structure does not prevent toxin binding with the channel but it has changed its pharmacological profile and potency. According to computer modeling data, the δ-SHTX-Hcr1f binds within the extracellular region of the rNaV1.2 voltage-sensing domain IV and pore-forming domain I through a network of strong interactions, and an additional fixation of the toxin at the channel binding site is carried out through the phospholipid environment. Our data suggest that Heteractis toxins could be used as molecular tools for NaV channel studies or insecticides rather than as pharmacological agents.
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Affiliation(s)
- Rimma S. Kalina
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Science, 690022 Vladivostok, Russia; (E.A.Z.); (P.S.D.); (A.N.K.); (N.Y.K.); (E.V.L.); (E.P.K.); (M.M.M.)
| | - Steve Peigneur
- Toxicology and Pharmacology, University of Leuven (KU Leuven), Campus Gasthuisberg, O&N 2, Herestraat~49, P.O. Box 922, 3000 Leuven, Belgium
| | - Elena A. Zelepuga
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Science, 690022 Vladivostok, Russia; (E.A.Z.); (P.S.D.); (A.N.K.); (N.Y.K.); (E.V.L.); (E.P.K.); (M.M.M.)
| | - Pavel S. Dmitrenok
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Science, 690022 Vladivostok, Russia; (E.A.Z.); (P.S.D.); (A.N.K.); (N.Y.K.); (E.V.L.); (E.P.K.); (M.M.M.)
| | - Aleksandra N. Kvetkina
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Science, 690022 Vladivostok, Russia; (E.A.Z.); (P.S.D.); (A.N.K.); (N.Y.K.); (E.V.L.); (E.P.K.); (M.M.M.)
| | - Natalia Y. Kim
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Science, 690022 Vladivostok, Russia; (E.A.Z.); (P.S.D.); (A.N.K.); (N.Y.K.); (E.V.L.); (E.P.K.); (M.M.M.)
| | - Elena V. Leychenko
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Science, 690022 Vladivostok, Russia; (E.A.Z.); (P.S.D.); (A.N.K.); (N.Y.K.); (E.V.L.); (E.P.K.); (M.M.M.)
| | - Jan Tytgat
- Toxicology and Pharmacology, University of Leuven (KU Leuven), Campus Gasthuisberg, O&N 2, Herestraat~49, P.O. Box 922, 3000 Leuven, Belgium
| | - Emma P. Kozlovskaya
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Science, 690022 Vladivostok, Russia; (E.A.Z.); (P.S.D.); (A.N.K.); (N.Y.K.); (E.V.L.); (E.P.K.); (M.M.M.)
| | - Margarita M. Monastyrnaya
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Science, 690022 Vladivostok, Russia; (E.A.Z.); (P.S.D.); (A.N.K.); (N.Y.K.); (E.V.L.); (E.P.K.); (M.M.M.)
| | - Irina N. Gladkikh
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Science, 690022 Vladivostok, Russia; (E.A.Z.); (P.S.D.); (A.N.K.); (N.Y.K.); (E.V.L.); (E.P.K.); (M.M.M.)
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4
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Functional discrimination of sea anemone neurotoxins using 3D-plotting. Open Life Sci 2009. [DOI: 10.2478/s11535-008-0064-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
AbstractOne of the most important goals in structural biology is the identification of functional relationships among the structure of proteins and peptides. The purpose of this study was to (1) generate a model based on theoretical and computational considerations among amino acid sequences within select neurotoxin peptides, and (2) compare the relationship these values have to the various toxins tested. We employed isolated neurotoxins from sea anemones with established specific potential to act on voltage-dependent sodium and potassium channel activity as our model. Values were assigned to each amino acid in the peptide sequence of the neurotoxins tested using the Number of Lareo and Acevedo algorithm (NULA). Once the NULA number was obtained, it was then plotted using three dimensional space coordinates. The results of this study allow us to report, for the first time, that there is a different numerical and functional relationship between the sequences of amino acids from sea anemone neurotoxins, and the resulting numerical relationship for each peptide, or NULA number, has a unique location in three-dimensional space.
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Cunha RB, Santana ANC, Amaral PC, Carvalho MDF, Carvalho DMF, Cavalheiro EA, Maigret B, Ricart CAO, Cardi BA, Sousa MV, Carvalho KM. Primary structure, behavioral and electroencephalographic effects of an epileptogenic peptide from the sea anemone Bunodosoma cangicum. Toxicon 2005; 45:207-17. [PMID: 15626370 DOI: 10.1016/j.toxicon.2004.10.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2004] [Revised: 10/11/2004] [Accepted: 10/13/2004] [Indexed: 10/26/2022]
Abstract
The primary structure of cangitoxin (CGX), a 4958 Da peptide from the sea anemone Bunodosoma cangicum, was determined: GVACRCDSDGPTVRGNSLSGTLWLTGGCPSGWHNCRGSGPFIGYCCKK. CGX contains all the 11 residues that are conserved and the 5 that are conservatively substituted within or between the type 1 and type 2 sequences of sea anemone peptides with specific action on voltage-sensitive sodium channels. Furthermore, it also has 6 identities (Asp9, Arg14, Asn16, Leu18, Trp33 and Lys48) and 1 homology (Arg36) in the 8 residues of the pharmacophore of the sea anemone ApB which are essential for interaction with mammalian sodium channels. The intrahippocampal injection of CGX induces several sequential behavioral alterations--episodes of akinesia alternating with facial automatisms and head tremor, salivation, rearing, jumping, barrel-rolling, wet dog shakes and forelimb clonic movements--and the electroencephalography analysis shows that they were followed by important seizure periods that gradually evolved to status epilepticus that lasted 8-12 h, similar to that observed in the acute phase of the pilocarpine model of epilepsy. These results suggest that CGX may be an important tool to develop a new experimental model of status epilepticus which may contribute to understanding the etiology of epilepsy and to test the effects of new antiepileptic drugs.
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Affiliation(s)
- Ricardo B Cunha
- Centro Brasileiro de Serviços e Pesquisas em Proteínas, Departamento de Biologia Celular, Universidade de Brasília, CEP 70.910-900 Brasília, DF, Brazil
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Shiomi K, Honma T, Ide M, Nagashima Y, Ishida M, Chino M. An epidermal growth factor-like toxin and two sodium channel toxins from the sea anemone Stichodactyla gigantea. Toxicon 2003; 41:229-36. [PMID: 12565742 DOI: 10.1016/s0041-0101(02)00281-7] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Three peptide toxins (gigantoxins I-III) with crab toxicity were isolated from the sea anemone Stichodactyla gigantea by gel filtration on Sephadex G-50 and reverse-phase HPLC on TSKgel ODS-120T and their complete amino acid sequences were determined. Gigantoxins II (44 residues) and III (48 residues) have LD(50) (against crabs) of 70 and 120 microg/kg, respectively, and are analogous to the known type 1 and 2 sea anemone sodium channel toxins, respectively. On the other hand, gigantoxin I (48 residues) is potently paralytic to crabs (ED(50) 215 microg/kg), although its lethality is very weak (LD(50)>1000 microg/kg). Interestingly, gigantoxin I has 31-33% homologies with mammalian epidermal growth factors (EGFs), with the same location of six cysteine residues. In accordance with the sequence similarity, gigantoxin I exhibits EGF activity as evidenced by rounding of A431 cells and tyrosine phosphorylation of the EGF receptor in the cells, although much less potently than human EGF. Gigantoxin I is the first example of EGF-like toxins of natural origin.
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Affiliation(s)
- Kazuo Shiomi
- Department of Food Science and Technology, Tokyo University of Fisheries, Konan-4, Minato-ku, 108-8477, Tokyo, Japan.
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Ishida M, Yokoyama A, Shimakura K, Nagashima Y, Shiomi K. Halcurin, a polypeptide toxin from the sea anemone Halcurias sp., with a structural resemblance to type 1 and 2 toxins. Toxicon 1997; 35:537-44. [PMID: 9133708 DOI: 10.1016/s0041-0101(96)00143-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The aqueous extract of the sea anemone Halcurias sp. belonging to the suborder Endocoelantheae was found to be potently lethal to crabs, although it showed neither lethal activity in mice nor hemolytic activity. A polypeptide toxin (named halcurin) with a LD50 of 5.8 micrograms/kg against crabs was isolated by gel filtration on Sephadex G-50 and reverse-phase high-performance liquid chromatography on TSKgel ODS-120T. The complete amino acid sequence of halcurin comprising 47 residues was elucidated by sequence analysis of the native molecule and its enzymatic fragment. Comparison with the known sea anemone polypeptide toxins (types 1-3), which are all from members of the suborder Nynantheae, revealed a high sequence homology (49-74%) of halcurin with type 2 toxins. Also, halcurin has several residues conserved for only type 1 toxins. These results, together with the fact the Halcurias sp. is a more primitive species than members of Nynantheae, suggest that type 1 and 2 toxins have evolved from a common ancestor with a sequence more similar to halcurin.
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Affiliation(s)
- M Ishida
- Department of Food Science and Technology, Tokyo University of Fisheries, Japan
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Monks SA, Gould AR, Lumley PE, Alewood PF, Kem WR, Goss NH, Norton RS. Limited proteolysis study of structure-function relationships in Sh I, a polypeptide neurotoxin from a sea anemone. BIOCHIMICA ET BIOPHYSICA ACTA 1994; 1207:93-101. [PMID: 7913833 DOI: 10.1016/0167-4838(94)90056-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The structure-function relationships of the neurotoxic polypeptide Sh I, from the sea anemone Stichodactyla helianthus, have been studied using limited proteolysis with trypsin and endoproteinase Lys-C. Major products from each of the proteolytic digests were characterised using N-terminal peptide sequencing and amino-acid analysis or mass spectrometry. Of the six possible tryptic cleavage sites in Sh I, the bonds adjacent to Arg-13 and Lys-47 were found to be the most susceptible, complete cleavage occurring within minutes. Cleavages adjacent to Lys-32 and Lys-46 proceeded more slowly and cleavage adjacent to Arg-45 was the slowest. The sixth potential site, adjacent to Lys-4, was not cleaved at all. All derivatives were inactive as crustacean neurotoxins. Cleavage with endoproteinase Lys-C generated two major products. Derivatives cleaved adjacent to Lys-32 and either Lys-46 or Lys-47 were isolated. Both were inactive, indicating that either cleavage adjacent to Lys-32 or the removal of the C-terminal lysine residue(s) was sufficient to abolish activity. Lys-4 again was refractory to cleavage. The sequence of cleavage events correlated well with the static accessibility of the lysyl and arginyl side chains and to a lesser extent with the accessibility of the carbonyl oxygen of susceptible peptide bonds, as measured from the solution structure of Sh I determined by 1H-NMR. In the case of Lys-4, the lack of cleavage by trypsin and endoproteinase Lys-C may reflect a lack of flexibility in this region. The effects of the various cleavages on biological activity emphasise that the surface of the protein near the reverse turn encompassing Asp-6, Asp-7 and Glu-8 is essential for activity.
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Affiliation(s)
- S A Monks
- School of Biochemistry, University of New South Wales, Kensington, Australia
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Hinds MG, Norton RS. Sequential 1H-NMR assignments of neurotoxin III from the sea anemone Heteractis macrodactylus and structural comparison with related toxins. JOURNAL OF PROTEIN CHEMISTRY 1993; 12:371-8. [PMID: 8104412 DOI: 10.1007/bf01028199] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The complete sequence-specific assignment of resonances in the 1H-NMR spectrum of the polypeptide neurotoxin III (Hm III) from the sea anemone Heteractis macrodactylus is described. Comparison of the chemical shifts and pattern of NOEs for Hm III with those for the related toxin Hp III from Heteractis paumotensis, which differs only in the substitution of Asn for Tyr at position 11, shows that the overall secondary and tertiary structures are conserved. The largest differences in chemical shift caused by the substitution at position 11 are observed for the NH resonances of Arg-13, Thr-14, Ala-15, Leu-17, and Cys-26. The C alpha H resonances influenced most are those of ASP-6, Gly-9, Leu-17, and Glu-42, while the most affected C beta H resonances are from Leu-17, Glu-28, and Lys-32. The absence of long-range NOEs to the aromatic ring of Tyr-11 as well as the lack of significant chemical shift effects on residues outside the loop comprising residues 7-16 confirm that this part of the loop makes no long-lived contacts with the rest of the molecule. The deviations from random coil shifts of Hm III are compared with those of the related anemone toxins Hp II, Hp III, and toxin I from Stichodactyla helianthus (Sh I). The similarity in deviations in chemical shift as a function of sequence position for these four toxins emphasizes the overall structural homology among these polypeptides.
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Affiliation(s)
- M G Hinds
- NMR Laboratory, Biomolecular Research Institute, Parkville, Australia
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Gould AR, Mabbutt BC, Llewellyn LE, Goss NH, Norton RS. Linear and cyclic peptide analogues of the polypeptide cardiac stimulant, anthopleurin-A. 1H-NMR and biological activity studies. EUROPEAN JOURNAL OF BIOCHEMISTRY 1992; 206:641-51. [PMID: 1318831 DOI: 10.1111/j.1432-1033.1992.tb16969.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A loop corresponding to residues 8-17 in the polypeptide cardiac stimulant anthopleurin-A is known to be important for the cardiostimulant activity of this molecule. To investigate the activity and possible conformations of this loop in isolation, two synthetic peptides have been studied. The first corresponds to residues 6-20 of anthopleurin-A with Cys6 replaced by Thr, and the second to residues 6-21 of anthopleurin-A, with Thr21 replaced by Cys. The introduction of an additional cysteine in the latter peptide enabled an intramolecular disulfide to be formed between the N- and C-terminal residues. Both linear peptides and the disulfide-containing analogue lack the cardiostimulant and Na(+-)-channel binding activity in the parent molecule, anthopleurin-A, indicating that although the loop is important for the function of anthopleurin-A, other regions of the molecule must also be involved in activity. Assignments of the 1H-NMR spectra of both peptides are presented, and their pH and temperature dependences investigated. The results show that the amide protons of Gly5 and Asn11 (corresponding to Gly10 and Asn16 in anthopleurin-A) sample hydrogen-bonded conformations in solution. Based on these NMR data, two regions of non-random structure, encompassing residues 2-5 and 8-11, respectively, are proposed, and the possible involvement of such structures in the activity of anthopleurin-A is discussed.
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Affiliation(s)
- A R Gould
- School of Biochemistry, University of New South Wales, Kensington, Australia
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12
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Wishart DS, Sykes BD, Richards FM. Relationship between nuclear magnetic resonance chemical shift and protein secondary structure. J Mol Biol 1991; 222:311-33. [PMID: 1960729 DOI: 10.1016/0022-2836(91)90214-q] [Citation(s) in RCA: 1502] [Impact Index Per Article: 45.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
An analysis of the 1H nuclear magnetic resonance chemical shift assignments and secondary structure designations for over 70 proteins has revealed some very strong and unexpected relationships. Similar studies, performed on smaller databases, for 13C and 15N chemical shifts reveal equally strong correlations to protein secondary structure. Among the more interesting results to emerge from this work is the finding that all 20 naturally occurring amino acids experience a mean alpha-1H upfield shift of 0.39 parts per million (from the random coil value) when placed in a helical configuration. In a like manner, the alpha-1H chemical shift is found to move downfield by an average of 0.37 parts per million when the residue is placed in a beta-strand or extended configuration. Similar changes are also found for amide 1H, carbonyl 13C, alpha-13C and amide 15N chemical shifts. Other relationships between chemical shift and protein conformation are also uncovered; in particular, a correlation between helix dipole effects and amide proton chemical shifts as well as a relationship between alpha-proton chemical shifts and main-chain flexibility. Additionally, useful relationships between alpha-proton chemical shifts and backbone dihedral angles as well as correlations between amide proton chemical shifts and hydrogen bond effects are demonstrated.
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Affiliation(s)
- D S Wishart
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511
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Mutagenesis of Cerebratulus lacteus neurotoxin B-IV identifies NH2-terminal sequences important for biological activity. J Biol Chem 1991. [DOI: 10.1016/s0021-9258(18)98777-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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14
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Norton RS. Structure and structure-function relationships of sea anemone proteins that interact with the sodium channel. Toxicon 1991; 29:1051-84. [PMID: 1686683 DOI: 10.1016/0041-0101(91)90205-6] [Citation(s) in RCA: 176] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Sea anemones produce a series of toxic polypeptides and proteins with molecular weights in the range 3000-5000 that act by binding to specific receptor sites on the voltage-gated sodium channel of excitable tissue. This article reviews our current knowledge of the molecular basis for activity of these molecules, with particular emphasis on recent results on their receptor binding properties, the role of individual residues in activity and receptor binding, and their three-dimensional structures as determined by nuclear magnetic resonance spectroscopy. A region of these molecules that constitutes at least part of the receptor binding domain is proposed.
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Affiliation(s)
- R S Norton
- School of Biochemistry, University of New South Wales, Kensington, Australia
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15
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Pennington MW, Kem WR, Norton RS, Dunn BM. Chemical synthesis of a neurotoxic polypeptide from the sea anemone Stichodactyla helianthus. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1990; 36:335-43. [PMID: 1981881 DOI: 10.1111/j.1399-3011.1990.tb01291.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The sea anemone Stichodactyla helianthus neurotoxin I, a 48-residue polypeptide, was synthesized by automated solid phase methodology. The fully reduced polypeptide was subsequently refolded in the presence of a glutathione oxidoreduction buffer to the biologically active species containing three disulfide bonds. The overall yield after rigorous purification was 12.5%. The circular dichroism (CD), and proton nuclear magnetic resonance (1H NMR) spectra of the HPLC-purified synthetic toxin were indistinguishable from those obtained concurrently with the natural toxin. A subtilisin digest of the synthetic neurotoxin generated peptide fragments identical to that of a sample of the natural toxin subjected to the same treatment. The toxicity of the synthetic polypeptide was identical to that of the natural toxin (crab LD50, 3.1 micrograms/kg). The equilibrium dissociation constant (28 nM) for interaction of the synthetic toxin with crab axolemma vesicles was nearly identical to that of the natural toxin (25 nM).
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Affiliation(s)
- M W Pennington
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville
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Fogh RH, Kem WR, Norton RS. Solution structure of neurotoxin I from the sea anemone Stichodactyla helianthus. A nuclear magnetic resonance, distance geometry, and restrained molecular dynamics study. J Biol Chem 1990. [DOI: 10.1016/s0021-9258(19)38261-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Kem WR, Parten B, Pennington MW, Price DA, Dunn BM. Isolation, characterization, and amino acid sequence of a polypeptide neurotoxin occurring in the sea anemone Stichodactyla helianthus. Biochemistry 1989; 28:3483-9. [PMID: 2568126 DOI: 10.1021/bi00434a050] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
An aqueous exudate collected from frozen and thawed bodies of a Caribbean sea anemone, Stichodactyla (formerly Stoichactis) helianthus, contained a polypeptide neurotoxin (Sh I) selectively toxic to crustaceans. The polypeptide was purified by G-50 Sephadex, phosphocellulose, and sulfopropyl-Sephadex chromatography and shown to have a molecular size of 5200 daltons and a pI of 8.3. The amino acid sequence determined by automatic Edman degradations of whole RCM Sh I and of its clostripain, staphylococcal protease, and cyanogen bromide digest peptides is A1ACKC5DDEGP10DIRTA15PLTGT20VDLGS25CNAGW30EKCAS35YYTII40ADCCR45KKK . Only 33% of this sequence is identical with the sequence of Anemonia sulcata toxin II, a sea anemone toxin isolated from the taxonomic family Actiniidae. The six half-cystines are located in equivalent positions to those of the actiniid toxins and account for nearly half of the residues common to all of the toxins. However, 69% of the Sh I sequence is identical with that of toxin II from Heteractis paumotensis, another sea anemone belonging to the family Stichodactylidae. Stichodactylid toxins lack the initial N-terminal residue of actiniid toxins and possess three consecutive acidic residues at positions 6-8, a single tryptophan at position 30, and four consecutive basic residues at positions 45-48 (C-terminus). A rabbit IgG prepared by Sh I immunization bound Sh I with a K0.5 of 4.7 nM but failed to bind homologous actiniid (Anemonia sulcata II, Condylactis gigantea III) or bolocerid (Bolocera tuedae II) polypeptide neurotoxins.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- W R Kem
- Department of Pharmacology and Therapeutics, University of Florida College of Medicine, Gainesville 32610
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19
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Nettesheim DG, Klevit RE, Drobny G, Watt DD, Krishna NR. Proton nuclear magnetic resonance studies on the variant-3 neurotoxin from Centruroides sculpturatus Ewing: sequential assignment of resonances. Biochemistry 1989; 28:1548-55. [PMID: 2719917 DOI: 10.1021/bi00430a019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
We report the sequential assignment of resonances to specific residues in the proton nuclear magnetic resonance spectrum of the variant-3 neurotoxin from the scorpion Centruroides sculpturatus Ewing (range southwestern U.S.A.). A combination of two-dimensional NMR experiments such as 2D-COSY, 2D-NOESY, and single- and double-RELAY coherence transfer spectroscopy has been employed on samples of the protein dissolved in D2O and in H2O for assignment purposes. These studies provide a basis for the determination of the solution-phase conformation of this protein and for undertaking detailed structure-function studies of these neurotoxins that modulate the flow of sodium current by binding to the sodium channels of excitable membranes.
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Affiliation(s)
- D G Nettesheim
- Comprehensive Cancer Center, University of Alabama, Birmingham 35294
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20
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Fogh RH, Mabbutt BC, Kem WR, Norton RS. Sequence-specific 1H NMR assignments and secondary structure in the sea anemone polypeptide Stichodactyla helianthus neurotoxin I. Biochemistry 1989; 28:1826-34. [PMID: 2566324 DOI: 10.1021/bi00430a060] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Sequence-specific assignments are reported for the 500-MHz 1H nuclear magnetic resonance (NMR) spectrum of the 48-residue polypeptide neurotoxin I from the sea anemone Stichodactyla helianthus (Sh I). Spin systems were first identified by using two-dimensional relayed or multiple quantum filtered correlation spectroscopy, double quantum spectroscopy, and spin lock experiments. Specific resonance assignments were then obtained from nuclear Overhauser enhancement (NOE) connectivities between protons from residues adjacent in the amino acid sequence. Of a total of 265 potentially observable resonances, 248 (i.e., 94%) were assigned, arising from 39 completely and 9 partially assigned amino acid spin systems. The secondary structure of Sh I was defined on the basis of the pattern of sequential NOE connectivities, NOEs between protons on separate strands of the polypeptide backbone, and backbone amide exchange rates. Sh I contains a four-stranded antiparallel beta-sheet encompassing residues 1-5, 16-24, 30-33, and 40-46, with a beta-bulge at residues 17 and 18 and a reverse turn, probably a type II beta-turn, involving residues 27-30. No evidence of alpha-helical structure was found.
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Affiliation(s)
- R H Fogh
- School of Biochemistry, University of New South Wales, Kensington, Australia
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21
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Norton RS, Cossins AI, Kem WR. 1H NMR study of the solution properties of the polypeptide neurotoxin I from the sea anemone Stichodactyla helianthus. Biochemistry 1989; 28:1820-6. [PMID: 2566323 DOI: 10.1021/bi00430a059] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The solution properties of the polypeptide neurotoxin I from the sea anemone Stichodactyla helianthus (Sh I) have been investigated by high-resolution 1H nuclear magnetic resonance (NMR) spectroscopy at 300 MHz. The pH dependence of the spectra has been examined over the range 1.1-12.2 at 27 degrees C. Individual pKa values have been obtained for the alpha-ammonium group of Ala-1 (8.6) and the side chains of Glu-8 (3.7), Tyr-36 (10.9), and Tyr-37 (10.8). For the remaining seven carboxyl groups in the molecule (from five Asp, Glu-31, and the C-terminus), four pKa values, viz., 2.8, 3.5, 4.1 and 6.4, can be clearly identified. The five Lys residues titrate in the range 10.5-11, but individual pKa values could not be obtained because of peak overlap. Conformational changes associated with the protonation of carboxylates occur below pH 4, while in the alkaline pH range major unfolding occurs above pH 10. The molecule also unfolds at elevated temperatures, having a transition temperature of ca. 55 degrees C at pH 5.25. Exchange of the backbone amide protons has been monitored at various values of pH and temperature in the ranges pH 4-5 and 12-27 degrees C. Up to 18 slowly exchanging amides are observed, consistent with the existence of a core of hydrogen-bonded secondary structure, most probably beta-sheet.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- R S Norton
- School of Biochemistry, University of New South Wales, Kensington, Australia
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Abstract
Knowledge of three-dimensional protein structures is one of the foundations of protein design and protein engineering. Nuclear magnetic resonance spectroscopy was recently introduced as a second method for protein structure determination, in addition to the well-established diffraction techniques with protein single crystals. This new approach enables one to carry out detailed structural studies of proteins in solution and other noncrystalline states, which may be similar or identical to the physiological environment, and promises new insights into the dynamics of protein molecules and the protein-folding problem.
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Affiliation(s)
- K Wüthrich
- Eidgenössiche Technische Hochschule, Zürich, Switzerland
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23
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Widmer H, Billeter M, Wüthrich K. Three-dimensional structure of the neurotoxin ATX Ia from Anemonia sulcata in aqueous solution determined by nuclear magnetic resonance spectroscopy. Proteins 1989; 6:357-71. [PMID: 2576133 DOI: 10.1002/prot.340060403] [Citation(s) in RCA: 67] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
With the aid of 1H nuclear magnetic resonance (NMR) spectroscopy, the three-dimensional structure in aqueous solution was determined for ATX Ia, which is a 46 residue polypeptide neurotoxin of the sea anemone Anemonia sulcata. The input for the structure calculations consisted of 263 distance constraints from nuclear Overhauser effects (NOE) and 76 vicinal coupling constants. For the structure calculation several new or ammended programs were used in a revised strategy consisting of five successive computational steps. First, the program HABAS was used for a complete search of all backbone and chi 1 conformations that are compatible with the intraresidual and sequential NMR constraints. Second, using the program DISMAN, we extended this approach to pentapeptides by extensive sampling of all conformations that are consistent with the local and medium-range NMR constraints. Both steps resulted in the definition of additional dihedral angle constraints and in stereospecific assignments for a number of beta-methylene groups. In the next two steps DISMAN was used to obtain a group of eight conformers that contain no significant residual violations of the NMR constraints or van der Waals contacts. Finally, these structures were subjected to restrained energy refinement with a modified version of the molecular mechanics module of AMBER, which in addition to the energy force field includes potentials for the NOE distance constraints and the dihedral angle constraints. The average of the pairwise minimal RMS distances between the resulting refined conformers calculated for the well defined molecular core, which contains the backbone atoms of 35 residues and 20 interior side chains, is 1.5 +/- 0.3 A. This core is formed by a four-stranded beta-sheet connected by two well-defined loops, and there is an additional flexible loop consisting of the eleven residues 8-18. The core of the protein is stabilized by three disulfide bridges, which are surrounded by hydrophobic residues and shielded on one side by hydrophilic residues.
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Affiliation(s)
- H Widmer
- Institut für Molekularbiologie und Biophysik, Eidgenössische Technische Hochschule-Hönggerberg, Zürich, Switzerland
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24
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Abstract
The procedures outlined here have been used successfully for more than 30 proteins to date, and are nearly routine for molecules up to a molecular weight of 10,000. Some of the proteins assigned have a molecular weight greater than 10,000. For these larger proteins, relayed-COSY and TOCSY experiments have been essential for the identification of spin systems, although for thioredoxin these experiments could not be used. In this case, assignments were accomplished using nonspecific deuteration to the level of 75% and specific, nearly complete, deuteration of certain kinds of residues (see LeMaster [2], this volume). Nonspecific deuteration reduces the cross-relaxation rates of each proton to the rest of the molecule, thus reducing the linewidths. The cross-peak patterns were also narrowed due to simplification of the coupling patterns. Such a laborious procedure of nonspecific deuteration may not be necessary for complete proton assignments of proteins in this size range, as evidenced by the fact that this method was not used for the other two molecules mentioned above. It may prove, however, to be quite valuable in the study of larger molecules, where linewidths are expected to increase due to longer rotational correlation times. Overlap problems in the NH chemical shifts can be dealt with by making use of the differential temperature dependence of these shifts. Another technique is to take advantage of the wide range of exchange rates between these protons and the solvent. Spectra containing only the slowly exchanging NH protons can be obtained by acquiring spectra of the protein soon after dilution in D2O, and spectra of only the rapidly exchanging protons can be obtained by obtaining spectra in a freshly prepared H2O solution of the protein after having completely exchanged all the NH protons with deuterium. Variation of the pH will resolve problems of overlap in all regions of the spectrum, although many chemical shifts may be unaffected by pH. In some cases, pH variation may change the conformation of the molecule. This may, in fact, assist in the sequential assignment if the chemical shifts can be followed with pH. Finally, the relayed-NOESY experiments can resolve overlap problems with the alpha-proton chemical shifts. Thus, it is very likely that the assignment methods outlined here will be successful for the assignment of the proton spectra of even larger molecules if there is significant secondary structure and significant variety of residues to provide enough dispersion of the chemical shifts.(ABSTRACT TRUNCATED AT 400 WORDS)
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26
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Brugge JA, Buchanan BG, Jardetzky O. Toward automating the process of determining polypeptide secondary structure from1H NMR data. J Comput Chem 1988. [DOI: 10.1002/jcc.540090612] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Widmer H, Wagner G, Schweitz H, Lazdunski M, Wüthrich K. The secondary structure of the toxin ATX Ia from Anemonia sulcata in aqueous solution determined on the basis of complete sequence-specific 1H-NMR assignments. EUROPEAN JOURNAL OF BIOCHEMISTRY 1988; 171:177-92. [PMID: 2892680 DOI: 10.1111/j.1432-1033.1988.tb13774.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The toxin preparations ATX I, ATX Ia and ATX Ib from Anemonia sulcata were investigated by proton nuclear magnetic resonance (NMR). High-resolution phase-sensitive two-dimensional NMR experiments were used to monitor the separation by high-performance liquid chromatography of the two isoproteins ATX Ia and ATX Ib. For ATX Ia complete sequence-specific resonance assignments were obtained and the secondary structure was determined. To obtain the NMR assignments we used a variant of the sequential assignment technique which relied extensively on cross-peak fine-structure analysis in phase-sensitive spectra, using spectrum simulations based on density matrix calculations with the program SPHINX. These procedures, which resulted in extensive amino acid spin system identifications prior to the sequential assignments, should be generally applicable for small proteins with relatively narrow 1H-NMR lines. The secondary structure of ATX I includes a beta sheet consisting of four strands. No evidence was found for the presence of regular helical segments. The four beta strands are connected by two extended loops and a tight turn, for which further characterization has to await the complete determination of the three-dimensional structure.
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Affiliation(s)
- H Widmer
- Institut für Molekularbiologie und Biophysik, Eidgenössische Technische Hochschule Zürich-Hönggerberg, Switzerland
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28
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Groß KH, Kalbitzer HR. Distribution of chemical shifts in 1H nuclear magnetic resonance spectra of proteins. ACTA ACUST UNITED AC 1988. [DOI: 10.1016/0022-2364(88)90203-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Lichtarge O, Jardetzky O, Li CH. Secondary structure determination of human beta-endorphin by 1H NMR spectroscopy. Biochemistry 1987; 26:5916-25. [PMID: 2960378 DOI: 10.1021/bi00392a051] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The 1H NMR spectra of human beta-endorphin indicate that the peptide exists in random-coil form in aqueous solution but becomes helical in mixed solvent. Thermal denaturation NMR experiments show that in water there is no transition between 24 and 75 degrees C, while a slow noncooperative thermal unfolding is observed in a 60% methanol-40% water mixed solvent in the same temperature range. These findings are consistent with circular dichroism studies by other workers concluding that beta-endorphin is a random coil in water but that it forms 50% alpha-helix or more in mixed solvents. The peptide in the mixed water-methanol solvent was further studied by correlated spectroscopy (COSY) and nuclear Overhauser effect spectroscopy (NOESY) experiments. These allow a complete set of assignments to be made and establish two distinct stretches over which the solvent induces formation of alpha-helices: the first occurs between Tyr-1 and Thr-12 and the second between Leu-14 and extending to Lys-28. There is evidence that the latter is capped by a turn occurring between Lys-28 and Glu-31. These helices form at the enkephalin receptor binding site, which is at the amino terminus, and at the morphine receptor binding site, located at the carboxyl terminus [Li, C. H. (1982) Cell (Cambridge, Mass.) 31, 504-505]. Our findings suggest that these two receptors may specifically recognize alpha-helices.
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Affiliation(s)
- O Lichtarge
- Stanford Magnetic Resonance Laboratory, Stanford University, California 94305-5055
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30
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Krebs HC, Habermehl GG. Isolierung und Strukturaufkl�rung eines h�molytisch aktiven Peptids aus der Seeanemone Metridium senile. Naturwissenschaften 1987. [DOI: 10.1007/bf00405472] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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31
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Metrione RM, Schweitz H, Walsh KA. The amino acid sequence of toxin RpIII from the sea anemone, Radianthus paumotensis. FEBS Lett 1987; 218:59-62. [PMID: 2885222 DOI: 10.1016/0014-5793(87)81018-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The amino acid sequence of the sodium channel toxin RpIII from the sea anemone Radianthus paumotensis has been determined. The protein is homologous with five analogous toxins from three anemone species, and is most similar to a less toxic protein, RpII, from the same organism. Twelve residues are conserved in all six toxins, one of which is an arginine residue thought to be essential for toxicity. The others (Cys, Gly, Pro and Trp) tend to be conserved in other sets of homologous proteins to maintain functional folds. Comparisons of the sequences suggest the existence of two separate but related classes of toxins cumon the three species of anemone.
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32
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Kay LE, Jones PJ, Prestegard J. Strong coupling effects in the homonuclear RELAY experiment, with applications to leucine spin systems of octanoyl-acyl carrier protein. ACTA ACUST UNITED AC 1987. [DOI: 10.1016/0022-2364(87)90307-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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