Abstract
There is a wide variety of ion channel types with various types of blockers, making research in this field very complicated. To reduce this complexity, it is essential to study ion channels and their blockers independently. Scorpion toxins, a major class of blockers, are charged short peptides with high affinities for potassium channels. Their high selectivity and inhibitory properties make them an important pharmacological tool for treating autoimmune or nervous system disorders. Scorpion toxins typically have highly charged surfaces and—like other proteins—an intrinsic ability to bind ions (Friedman J Phys Chem B 115(29):9213–9223, 1996; Baldwin Biophys J 71(4):2056–2063, 1996; Vrbka et al. Proc Natl Acad Sci USA 103(42):15440–15444, 2006a; Vrbka et al. J Phys Chem B 110(13):7036-43, 2006b). Thus, their effects on potassium channels are usually investigated in various ionic solutions. In this work, computer simulations of protein structures were performed to analyze the structural properties of the key residues (i.e., those that are presumably involved in contact with the surfaces of the ion channels) of 12 scorpion toxins. The presence of the two most physiologically abundant cations, Na+ and K+, was considered. The results indicated that the ion-binding properties of the toxin residues vary. Overall, all of the investigated toxins had more stable structures in ionic solutions than in water. We found that both the number and length of elements in the secondary structure varied depending on the ionic solution used (i.e., in the presence of NaCl or KCl). This study revealed that the ionic solution should be chosen carefully before performing experiments on these toxins. Similarly, the influence of these ions should be taken into consideration in the design of toxin-based pharmaceuticals.
Similar content being viewed by others
References
Lecomte C, Sabatier JM, Van Rietschoten J, Rochat H (1998) Synthetic peptides as tools to investigate the structure and pharmacology of potassium channel-acting short-chain scorpion toxins. Biochimie 80(2):151–154
Chen SW, Pellequer JL (2004) Identification of functionally important residues in proteins using comparative models. Curr Med Chem 11:595–605
Lourenco WR (1994) Diversity and endemism in tropical versus temperate scorpion communities. Biogiographica 70:155–160
Possani LD, Merino E, Corona M, Bolivar F, Becerril B (2000) Peptides and genes coding for scorpion toxins that affect ion-channels. Biochimie 82:861–868
Possani LD, Becerril B, Delepierre M, Tytgat J (1999) Scorpion toxins specific for Na+-channels. Eur J Biochem 264(2):287–300
Tytgat J, Chandy KG, Garcia ML, Gutman GA, Martin-Eauclaire MF, van der Walt JJ, Possani LD (1999) A unified nomenclature for short-chain peptides isolated from scorpion venoms: α-KTx molecular subfamilies. Trends Pharmacol Sci 20(11):444–447
Ashcroft FM (2000) Ion channels and diseases, 2nd edn. Academic, New York
Wrisch A, Grissmer S (2000) Structural differences of bacterial and mammalian K+ channels. J Biol Chem 275:39345–39353
Ashcroft FM (2006) From molecule to malady. Nature 440:440–447
Miller C (1995) The charybdotoxin family of K+ channel-blocking peptides. Neuron 15(1):5–10
Thompson J, Begenisich T (2000) Electrostatic interaction between charybdotoxin and a tetrameric mutant of Shaker K+ channels. Biophys J 78:2382–2391
Garcia-Valdes J, Zamudio FZ, Toro L, Possani LD (2001) Slotoxin, αKTx1.11, a new scorpion peptide blocker of MaxiK channels that differentiates between α and α + β (β1 or β4) complexes. FEBS Lett 505:369–373
Chandy KG, Wulff H, Beeton C, Pennington M, Gutman GA, Cahalan MD (2004) K+ channels as targets for specific immunomodulation. Trends Pharmacol Sci 25(5):280–289
Cornet B, Bonmatin JM, Hetru C, Hoffmann JA, Ptak M, Vovelle F (1995) Refined three-dimensional solution structure of insect defensin A. Structure 3:435–448
Kobayashi Y, Takashima H, Tamaoki H et al (1991) The cystine-stabilized alpha-helix: a common structural motif of ion-channel blocking neurotoxic peptides. Biopolymers 31:1213–1220
Aiyar J, Withka JM, Rizzi JP, Singleton DH, Andrews GC, Lin W, Boyd J, Hanson DG, Simon M, Dethlefs B, Lee CL, Hall JE, Gutman GA, Chandy KG (1995) Topology of the pore-region of a K+ channel revealed by the NMR-derived structures of scorpion toxins. Neuron 15:1169–1181
Park CS, Miller C (1992) Interaction of charybdotoxin with permeant ions inside the pore of a K+ channel. Neuron 9(2):307–313
Anderson CS, MacKinnon R, Smith C, Miller C (1988) Charybdotoxin block of single Ca2+-activated K+ channels. Effects of channel gating, voltage, and ionic strength. J Gen Physiol 91(3):317–333
Avdonin V, Nolan B, Sabatier JM, De Waard M, Hoshi T (2000) Mechanisms of maurotoxin action on Shaker potassium channels. Biophys J 79(2):776–787
Ellis KC, Tenenholz TC, Jerng H, Hayhurst M, Dudlak CS, Gilly WF, Blaustein MP, Weber DJ (2001) Interaction of a toxin from the scorpion Tityus serrulatus with a cloned K+ channel from squid (sqKv1A). Biochemistry 40:5942–5953
Garcia ML, Gao YD, McManus OB, Kaczorowski GJ (2001) Potassium channels: from scorpion venoms to high-resolution structure. Toxicon 39:739–748
Gómez-Lagunas F, Batista CV, Olamendi-Portugal T, Ramírez-Domínguez ME, Possani LD (2004) Inhibition of the collapse of the Shaker K+ conductance by specific scorpion toxins. J Gen Physiol 123(3):265–279
Fernandez I, Romi R, Szendeffy S, Martin-Eauclaire MF, Rochat H, Van Rietschoten J, Pons M, Giralt E (1994) Kaliotoxin (1–37) shows structural differences with related potassium channel blockers. Biochemistry 33(47):14256–14263
Darbon H, Blanc E, Sabatier JM (1999) Three-dimensional structure of scorpion toxins: towards a new model of interaction with potassium channels. In: Darbon H, Sabatier JM (eds) Perspectives in drug discovery and design: animal toxins and potassium channels, vol 15/16. Kluwer, Dordrecht, pp 40–60
Peter JM, Varga Z, Hajdu PR, Gaspar J, Damjanovich S, Horjales E, Possani LD (2001) Effects of toxins Pi2 and Pi3 on human T lymphocyte Kv1.3 channels: the role of Glu-7 and Lys24. J Membrane Biol 179:13–25
Mouhat S, Mosbah A, Visan V, Wulff H, Delepierre M, Darbon H, Grissmer S, De Waard M, Sabatier JM (2004) The ‘functional’ dyad of scorpion toxin Pi1 is not itself a prerequisite for toxin binding to the voltage-gated Kv1.2 potassium channels. Biochem J 377(Pt 1):25–36
Krezel AM, Kasibhatla C, Hidalgo P, MacKinnon R, Wagner G (1995) Solution structure of the potassium channel inhibitor agitoxin 2: caliper for probing channel geometry. Protein Sci 4(8):1478–1489
Zhang N, Chen X, Li M, Cao C, Wang Y, Wu G, Hu G, Wu H (2004) Solution structure of BmKK4, the first member of subfamily alpha-KTx 17 of scorpion toxins. Biochemistry 43(39):12469–12476
Jouirou B, Mosbah A, Visan V, Grissmer S, M’Barek S, Fajloun Z, Van Rietschoten J, Devaux C, Rochat H, Lippens G, El Ayeb M, De Waard M, Mabrouk K, Sabatier JM (2004) Cobatoxin 1 from Centruroides noxius scorpion venom: chemical synthesis, three dimensional structure in solution, pharmacology and docking on K+ channels. Biochem J 377(Pt 1):37–49
Bontems F, Gilquin B, Roumestand C, Ménez A, Toma F (1992) Analysis of side-chain organization on a refined model of charybdotoxin: structural and functional implications. Biochemistry 31(34):7756–7764
Savarin P, Romi-Lebrun R, Zinn-Justin S, Lebrun B, Nakajima T, Gilquin B, Menez A (1999) Structural and functional consequences of the presence of a fourth disulfide bridge in the scorpion short toxins: solution structure of the potassium channel inhibitor HsTX1. Protein Sci 8(12):2672–2685
Renisio JG, Lu Z, Blanc E, Jin W, Lewis JH, Bornet O, Darbon H (1999) Solution structure of potassium channel-inhibiting scorpion toxin Lq2. Proteins 34(4):417–426
Blanc E, Sabatier JM, Kharrat R, Meunier S, el Ayeb M, Van Rietschoten J, Darbon H (1997) Solution structure of maurotoxin, a scorpion toxin from Scorpio maurus, with high affinity for voltage-gated potassium channels. Proteins 29(3):321–333
Johnson BA, Stevens SP, Williamson JM (1994) Determination of the three-dimensional structure of margatoxin by 1H, 13C, 15N triple-resonance nuclear magnetic resonance spectroscopy. Biochemistry 33(50):15061–15070
Dauplais M, Gilquin B, Possani LD, Gurrola-Briones G, Roumestand C, Ménez A (1995) Determination of the three-dimensional solution structure of noxiustoxin: analysis of structural differences with related short-chain scorpion toxin. Biochemistry 34(51):16563–16573
Jaravine VA, Nolde DE, Reibarkh MJ, Korolkova YV, Kozlov SA, Pluzhnikov KA, Grishin EV, Arseniev AS (1997) Three-dimensional structure of toxin OSK1 from Orthochirus scrobiculosus scorpion venom. Biochemistry 36(6):1223–1232
Tenenholz TC, Rogowski RS, Collins JH, Blaustein MP, Weber DJ (1997) Solution structure for Pandinus toxin K-alpha (PiTX-K alpha), a selective blocker of A-type potassium channels. Biochemistry 36(10):2763–2771
Berendsen HJC, van der Spoel D, van Drunen R (1995) GROMACS: a message-passing parallel molecular dynamics implementation. Comput Phys Commun 91:43–56
Lindahl E, Hess B, van der Spoel D (2001) GROMACS 3.0: a package for molecular simulation and trajectory analysis. J Mol Model 7:306–317
Jorgensen WL, Maxwell DS, Tirado-Rives J (1996) Development and testing of the OPLS all-atom force field on conformational energetics and properties of organic liquids. J Am Chem Soc 118:11225–11236
Khabiri M, Nikouee A, Cwiklik L, Grissmer S, Ettrich R (2011) Charybdotoxin unbinding from the mKv1.3 potassium channel: a combined computational and experimental study. J Phys Chem B 115(39):11490–11500
Jorgensen WL, Chandrasekhar J, Madura JD, Impey RW, Klein ML (1983) Comparison of simple potential functions for simulating liquid water. J Chem Phys 79:926–935
Petsko GA (2004) Protein structure and function. New Science, London
Wetzel R, Perry LJ, Baase WA, Becktel WJ (1988) Disulfide bonds and thermal stability in T4 lysozyme. Proc Natl Acad Sci USA 85(2):401–405
Yu X, Tan NJ, Xiao R, Xu Y (2012) Engineering a disulfide bond in the lid hinge region of Rhizopus chinensis lipase: increased thermos ability and altered acyl chain length specificity. PLoS One 7(10):e46388
Melnik BS, Povarnitsyna TV, Glukhov AS, Melnik TN, Uversky VN (2012) Sarma RH (2012) SS-stabilizing proteins rationally: intrinsic disorder-based design of stabilizing disulphide bridges in GFP. J Biomol Struct Dyn 29(4):815–824
Berendsen HJC, Postma JPM, van Gunsteren WF, DiNola A, Haak JR (1984) Molecular dynamics with coupling to an external bath. J Chem Phys 81:3684–3690
Essmann U, Perera L, Berkowitz M (1995) A smooth particle mesh Ewald method. J Chem Phys 103:8577–8592
Hess B, Bekker H, Berendsen HJC, Fraaije JG (1997) LINCS: a linear constraint solver for molecular simulations. J Comput Chem 18:1463–1742
Humphrey W, Dalke A, Schulten K (1996) VMD—visual molecular dynamics. J Mol Graph 14:33–38
DeLano WL (2002) The PyMOL molecular graphics system. DeLano Scientific, San Carlos
Kabsch W, Sander C (1983) Dictionary of protein secondary structure: pattern recognition of hydrogen-bonded and geometrical features. Biopolymers 22(12):2577–2637
Štěpánková V, Paterová J, Damborský J, Jungwirth P, Chaloupková R, Heyda J (2013) Cation-specific effects on enzymatic catalysis driven by interactions at the tunnel mouth. J Phys Chem B 117(21):6394–6402
Chen X, Weber I, Harrison RW (2008) Hydration water and bulk water in proteins have distinct properties in radial distributions calculated from 105 atomic resolution crystal structures. J Phys Chem B 112(38):12073–12080
Grottesi A, Sansom MS (2003) Molecular dynamics simulations of a K+ channel blocker: Tc1 toxin from Tityus cambridgei. FEBS Lett 535(1–3):29–33
Nikouee A, Khabiri M, Grissmer S, Ettrich R (2012) Charybdotoxin and margatoxin acting on the human voltage-gated potassium channel hKv1.3 and its H399N mutant: an experimental and computational comparison. J Phys Chem B 116(17):5132–5140
Soares CM, Teixeira VH, Baptista AM (2003) Protein structure and dynamics in nonaqueous solvents: insights from molecular dynamics simulation studies. Biophys J 84:1628–1641
Crevenna AH, Naredi-Rainer N, Lamb DC, Wedlich-Söldner R, Dzubiella J (2012) Effects of Hofmeister ions on the α-helical structure of proteins. Biophys J 102(4):907–915
Hidalgo P, MacKinnon R (1995) Revealing the architecture of a K+ channel pore through mutant cycles with a peptide inhibitor. Science 268(5208):307–310
Gross A, MacKinnon R (1996) Agitoxin footprinting the Shaker potassium channel pore. Neuron 16(2):399–406
Li MH, Zhang NX, Chen XQ, Wu G, Wu HM, Hu GY (2003) BmKK4, a novel toxin from the venom of Asian scorpion Buthus martensi Karsch, inhibits potassium currents in rat hippocampal neurons in vitro. Toxicon 42(2):199–205
Rashid MH, Huq R, Tanner MR, Chhabra S, Khoo KK, Estrada R, Dhawan V, Chauhan S, Pennington MW, Beeton C, Kuyucak S, Norton RS (2014) A potent and Kv1.3-selective analogue of the scorpion toxin HsTX1 as a potential therapeutic for autoimmune diseases. Sci Rep 4:4509. doi:10.1038/srep04509
Doyle DA, Morais Cabral J, Pfuetzner RA, Kuo A, Gulbis JM, Cohen SL, Chait BT, MacKinnon R (1998) The structure of the potassium channel: molecular basis of K+ conduction and selectivity. Science 280(5360):69–77
Martin-Eauclaire MF, Bougis PE (2012) Potassium channels blockers from the venom of Androctonus mauretanicus mauretanicus. J Toxicol 2012:103608. doi:10.1155/2012/103608
Sandhiya S, Dkhar SA (2009) Potassium channels in health, disease & development of channel modulators. Indian J Med Res 29(3):223–232
Gairí M, Romi R, Fernández I, Rochat H, Martin-Eauclaire MF, Van Rietschoten J, Pons M, Giralt E (1997) 3D structure of kaliotoxin: is residue 34 a key for channel selectivity? J Pept Sci 3(4):314–319
Lange A, Giller K, Hornig S, Martin-Eauclaire MF, Pongs O, Becker S, Baldus M (2006) Toxin-induced conformational changes in a potassium channel revealed by solid-state NMR. Nature 440(7086):959–962
Korukottu J, Schneider R, Vijayan V, Lange A, Pongs O, Becker S, Baldus M, Zweckstetter M (2008) High-resolution 3D structure determination of kaliotoxin by solid-state NMR spectroscopy. PLoS One 3(6). doi: 10.1371/journal.pone.0002359
Sansom MS, Shrivastava IH, Bright JN, Tate J, Capener CE, Biggin PC (2002) Potassium channels: structures, models, simulations. Biochim Biophys Acta 1565(2):294–307
Cui M, Shen J, Briggs JM, Luo X, Tan X, Jiang H, Chen K, Ji R (2001) Brownian dynamics simulations of interaction between scorpion toxin Lq2 and potassium ion channel. Biophys J 80(4):1659–1669
Goldstein SA, Pheasant DJ, Miller C (1994) The charybdotoxin receptor of a Shaker K+ channel: peptide and channel residues mediating molecular recognition. Neuron 12(6):1377–1388
Stampe P, Kolmakova-Partensky L, Miller C (1994) Intimations of potassium channel structure from a complete functional map of the molecular surface of charybdotoxin. Biochemistry 33(2):443–450
Fu W, Cui M, Briggs JM, Huang X, Xiong B, Zhang Y, Luo X, Shen J, Ji R, Jiang H, Chen K (2002) Brownian dynamics simulations of the recognition of the scorpion toxin maurotoxin with the voltage-gated potassium ion channels. Biophys J 83(5):2370–2385
Yi H, Qiu S, Wu Y, Li W, Wang B (2011) Differential molecular information of maurotoxin peptide recognizing IKCa and Kv1.2 channels explored by computational simulation. BMC Struct Biol 11:3. doi:10.1186/1472-6807-11-3
Kunqian Y, Wei F, Hong L, Xiaomin L, Kai XC, Jianping D, Jianhua S, Hualiang J (2004) Computational simulations of interactions of scorpion toxins with the voltage-gated potassium ion channel. Biophys J 86(6):3542–3555
Martínez F, Muñoz-Garay C, Gurrola G, Darszon A, Possani LD, Becerril B (1998) Site directed mutants of noxiustoxin reveal specific interactions with potassium channels. FEBS Lett 429(3):381–384
Mullmann TJ, Spence KT, Schroeder NE, Fremont V, Christian EP, Giangiacomo KM (2001) Insights into alpha-K toxin specificity for K+ channels revealed through mutations in noxiustoxin. Biochemistry 40(37):10987–10997
Mouhat S, Visan V, Ananthakrishnan S, Wulff H, Andreotti N, Grissmer S, Darbon H, De Waard M, Sabatier JM (2005) K+ channel types targeted by synthetic OSK1, a toxin from Orthochirus scrobiculosus scorpion venom. Biochem J 385:95–104
Chen R, Robinson A, Gordon D, Chung SH (2011) Modeling the binding of three toxins to the voltage-gated potassium channel (Kv1.3). Biophys J 101(11):2652–2660
Chen R, Chung SH (2013) Molecular dynamics simulations of scorpion toxin recognition by the Ca2+-activated potassium channel KCa3.1. Biophys J 105(8):1829–1837
Friedman R (2011) Ions and the protein surface revisited: extensive molecular dynamics simulations and analysis of protein structures in alkali-chloride solutions. J Phys Chem B 115(29):9213–9223
Mutter M, Maser F, Altmann KH, Toniolo C, Bonora GM (1985) Sequence dependence of secondary structure formation: conformational studies of host–guest peptides in alpha-helix and beta-structure supporting media. Biopolymers 24:1057–1074
Dado GP, Gellman SH (1993) Redox control of secondary in a designed peptide. J Am Chem Soc 115:12609–12610
Bergeron ZL, Bingham JP (2012) Scorpion toxins specific for potassium (K+) channels: a historical overview of peptide bioengineering. Toxins 4(11):1082–1119
Fajloun Z, Ferrat G, Carlier E, Fathallah M, Lecomte C, Sandoz G, di Luccio E, Mabrouk K, Legros C, Darbon H, Rochat H, Sabatier JM, De Waard M (2000) Synthesis, 1H NMR structure, and activity of a three-disulfide-bridged maurotoxin analog designed to restore the consensus motif of scorpion toxins. J Biol Chem 275(18):13605–13612
Ferrat G, Bernard C, Fremont V, Mullmann TJ, Giangiacomo KM, Darbon H (2001) Structural basis for alpha-K toxin specificity for K+ channels revealed through the solution 1H NMR structures of two noxiustoxin-iberiotoxin chimeras. Biochemistry 40(37):10998–11006
Lina C, Lee L (2003) A two-ionic-parameter approach for ion activity coefficients of aqueous electrolyte solutions. Fluid Phase Equilib 205(1):69–88
Uejio JS, Schwartz CP, Duffin AM, Drisdell WS, Cohen RC, Saykally RJ (2008) Characterization of selective binding of alkali cations with carboxylate by X-ray absorption spectroscopy of liquid microjets. Proc Natl Acad Sci USA 105(19):6809–6812
Collins KD, Neilson GW, Enderby JE (2007) Ions in water: characterizing the forces that control chemical processes and biological structure. Biophys Chem 128(2–3):95–104
Yang Z, Liu XJ, Chen C, Halling PJ (2010) Hofmeister effects on activity and stability of alkaline phosphatase. Biochim Biophys Acta 1804(4):821–828
Acknowledgments
The authors would like to thank Prof. Stephan Grissmer for valuable comments. Funding: L.C. acknowledges grant 13-06181S from the Czech Science Foundation.
Conflict of interest
The authors declare that they have no conflict of interest.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Nikouee, A., Khabiri, M. & Cwiklik, L. Scorpion toxins prefer salt solutions. J Mol Model 21, 287 (2015). https://doi.org/10.1007/s00894-015-2822-y
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s00894-015-2822-y