Karelin A A, Pluzhnikov K A, Tsetlin V I
Bioorg Khim. 1986 Apr;12(4):448-56.
It was discovered that illumination of the complex formed by the solubilized acetylcholine receptor from Torpedo marmorata and Lys25-p-azidobenzoyl derivative of neurotoxin II results in the appearance on the receptor of up to 4 additional binding sites. Acetylcholine and neurotoxin II, but not the long-chain neurotoxins bind specifically to these sites. The additional binding sites could be also detected after illuminating the receptor complex with other photoactivable derivatives, provided the latter were displaced from one of the two main binding sites by hexa(trifluoroacetyl)neurotoxin II. A similar, but less pronounced effect, was observed on binding Lys25 (Ac) derivative of neurotoxin II. The formation of the additional binding sites was found to depend on the activity of the receptor preparations as well as on the mutual influence of the two main toxin-binding sites.
研究发现，用来自电鳐的溶解型乙酰胆碱受体与神经毒素II的Lys25 - 对叠氮苯甲酰衍生物形成的复合物进行光照后，受体会出现多达4个额外的结合位点。乙酰胆碱和神经毒素II能特异性结合这些位点，而长链神经毒素则不能。在用其他可光活化衍生物照射受体复合物后，只要后者被六（三氟乙酰）神经毒素II从两个主要结合位点之一置换出来，也能检测到额外的结合位点。在用神经毒素II的Lys25（Ac）衍生物进行结合时，观察到了类似但不太明显的效果。发现额外结合位点的形成取决于受体制剂的活性以及两个主要毒素结合位点的相互影响。
