Zerrouk H, Laraba-Djebari F, Fremont V, Meki A, Darbon H, Mansuelle P, Oughideni R, van Rietschoten J, Rochat H, Martin-Eauclaire M F
National Centre for Scientific Research, URA 1455, University of the Mediterranean, Federated Research Institute INSERM Jean Roche, Northern Faculty of Medicine, Marseille, France.
Int J Pept Protein Res. 1996 Dec;48(6):514-21. doi: 10.1111/j.1399-3011.1996.tb00870.x.
A new peptide ligand of the small conductance Ca2+ activated K+ channels has been purified from the venom (obtained by manual rather than electrical stimulation of the scorpion Androctonus mauretanicus mauretanicus), by following the inhibition of the 125I-apamin binding to its receptor on rat brain synaptosomes. Only one step on a C18 reversed-phase high-performance liquid chromatography column was necessary to obtain PO1. Its K0.5 for the apamin binding site was 100 nM. The amino acid sequence of PO1 is different from those of leiurotoxin and PO5. For the first time the same peptide was also purified from the venoms of two other species of North African scorpions, Androctonus australis and Buthus occitanus tunetanus. PO1 was chemically synthesized by the solid-phase technique and fully characterized. A model of PO1 was constructed by amino acid replacement using PO5 nuclear magnetic resonance studies as the starting model. Structure-activity relationships between these toxins and their receptor are discussed.
通过追踪125I-蜂毒明肽与其在大鼠脑突触体上的受体结合的抑制情况，从毒液（通过人工而非电刺激摩洛哥杀人蝎获得）中纯化出一种小电导Ca2+激活K+通道的新型肽配体。在C18反相高效液相色谱柱上只需一步即可获得PO1。其对蜂毒明肽结合位点的K0.5为100 nM。PO1的氨基酸序列与类毒素和PO5不同。首次从另外两种北非蝎子——澳氏杀人蝎和北非黄肥尾蝎的毒液中也纯化出了相同的肽。PO1通过固相技术进行化学合成并进行了全面表征。以PO5核磁共振研究为起始模型，通过氨基酸置换构建了PO1的模型。讨论了这些毒素与其受体之间的构效关系。
