caa a22 4500 605513651 CHVBK 20210128100701.0 cr unu---uuuuu 210128e20151101xx s 000 0 eng 10.1007/s00894-015-2822-y doi (NATIONALLICENCE)springer-10.1007/s00894-015-2822-y Scorpion toxins prefer salt solutions [Elektronische Daten] [Azadeh Nikouee, Morteza Khabiri, Lukasz Cwiklik] 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. Springer-Verlag Berlin Heidelberg, 2015 Ionic solutions nationallicence Molecular dynamics nationallicence Nonaqueous media nationallicence Secondary structure nationallicence Nikouee Azadeh Institute of Applied Physiology, Ulm University, Ulm, Germany aut Khabiri Morteza Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 16610, Prague 6, Czech Republic aut Cwiklik Lukasz Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 16610, Prague 6, Czech Republic aut Journal of Molecular Modeling Springer Berlin Heidelberg 21/11(2015-11-01), 1-14 1610-2940 21:11<1 2015 21 894 https://doi.org/10.1007/s00894-015-2822-y text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00894-015-2822-y text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Nikouee Azadeh Institute of Applied Physiology, Ulm University, Ulm, Germany aut NATIONALLICENCE 700 1- Khabiri Morteza Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 16610, Prague 6, Czech Republic aut NATIONALLICENCE 700 1- Cwiklik Lukasz Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 16610, Prague 6, Czech Republic aut NATIONALLICENCE 773 0- Journal of Molecular Modeling Springer Berlin Heidelberg 21/11(2015-11-01), 1-14 1610-2940 21:11<1 2015 21 894