Berkut Antonina A, Usmanova Dinara R, Peigneur Steve, Oparin Peter B, Mineev Konstantin S, Odintsova Tatyana I, Tytgat Jan, Arseniev Alexander S, Grishin Eugene V, Vassilevski Alexander A
From the M. M. Shemyakin and Yu. A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117997, Russia, Moscow Institute of Physics and Technology (State University), Moscow 117303, Russia.
Laboratory of Toxicology and Pharmacology, University of Leuven, Leuven 3000, Belgium, and.
J Biol Chem. 2014 May 16;289(20):14331-40. doi: 10.1074/jbc.M113.530477. Epub 2014 Mar 26.
In this study, we present the spatial structure of the wheat antimicrobial peptide (AMP) Tk-AMP-X2 studied using NMR spectroscopy. This peptide was found to adopt a disulfide-stabilized α-helical hairpin fold and therefore belongs to the α-hairpinin family of plant defense peptides. Based on Tk-AMP-X2 structural similarity to cone snail and scorpion potassium channel blockers, a mutant molecule, Tk-hefu, was engineered by incorporating the functionally important residues from κ-hefutoxin 1 onto the Tk-AMP-X2 scaffold. The designed peptide contained the so-called essential dyad of amino acid residues significant for channel-blocking activity. Electrophysiological studies showed that although the parent peptide Tk-AMP-X2 did not present any activity against potassium channels, Tk-hefu blocked Kv1.3 channels with similar potency (IC50 ∼ 35 μm) to κ-hefutoxin 1 (IC50 ∼ 40 μm). We conclude that α-hairpinins are attractive in their simplicity as structural templates, which may be used for functional engineering and drug design.
在本研究中，我们展示了利用核磁共振光谱学研究的小麦抗菌肽（AMP）Tk-AMP-X2的空间结构。该肽被发现具有二硫键稳定的α-螺旋发夹结构，因此属于植物防御肽的α-发夹素家族。基于Tk-AMP-X2与芋螺毒素和蝎子钾通道阻滞剂的结构相似性，通过将来自κ-芋螺毒素1的功能重要残基整合到Tk-AMP-X2支架上，设计了一个突变分子Tk-hefu。设计的肽包含对通道阻断活性至关重要的所谓必需氨基酸二元组。电生理研究表明，尽管亲本肽Tk-AMP-X2对钾通道没有任何活性，但Tk-hefu阻断Kv1.3通道的效力与κ-芋螺毒素1相似（IC50约为35μm对IC50约为40μm）。我们得出结论，α-发夹素作为结构模板，因其简单性而具有吸引力，可用于功能工程和药物设计。
