Ramalingam K, Bello J
Department of Chemistry, Graduate School, State University of New York, Buffalo 14263.
Biochem J. 1992 Jun 15;284 ( Pt 3)(Pt 3):663-5. doi: 10.1042/bj2840663.
The cytolytic activity of the bee venom toxin, melittin, is abolished on permethylation of the ammonium groups into quaternary trimethylammonium groups. The loss of activity in permethylated melittin may result partly from the absence of the hydrogen bonding potential and partly from steric effects involving the bulky trimethylammonium groups. Displacing the trimethylammonium groups away from the backbone to relieve steric effects (by acylating melittin with glycine or 5-aminopentanoic acid followed by permethylation) restored moderate activity at 5-fold increase in concentration.
蜂毒毒素蜂毒肽的溶细胞活性在铵基团全甲基化形成季铵三甲铵基团后消失。全甲基化蜂毒肽活性的丧失可能部分是由于失去了氢键形成潜力，部分是由于涉及庞大三甲铵基团的空间效应。通过将三甲铵基团从主链上移开以减轻空间效应（用甘氨酸或5-氨基戊酸对蜂毒肽进行酰化，然后进行全甲基化），在浓度增加5倍时恢复了适度的活性。
