Demicheli C, Garnier-Suillerot A
Laboratoire de Chimie Bioinorganique, Université Paris Nord, Bobigny, France.
Eur J Biochem. 1994 May 1;221(3):1063-9. doi: 10.1111/j.1432-1033.1994.tb18825.x.
Binding of the antitumor compound mithramycin to dipalmitoyl-sn-glycerophosphocholine and dimyristoyl-sn-glycerophosphocholine (Myr2GroPCho) model membrane (small unilamellar vesicles, SUV) bilayers was shown to be dependent on the molecular packing of the lipids and on the presence of Zn2+ or Mg2+. The CD properties of mithramycin have been used to follow its complexation to Zn2+ and to Mg2+. In the absence of SUV, Mg2+ and Zn2+ are each able to form with mithramycin two types of complexes of different chirality: at low molar ratios of M2+ to mithramycin, a complex in the left-handed conformation is obtained whereas at high molar ratios the complex formed has the right-handed conformation. In the presence of Zn2+ or Mg2+, mithramycin binds to SUV in the gel-phase state as a dimer in the left-handed conformation. No binding is observed when SUV are in liquid-crystal state.
抗肿瘤化合物光神霉素与二棕榈酰 - sn - 甘油磷酸胆碱和二肉豆蔻酰 - sn - 甘油磷酸胆碱（Myr2GroPCho）模型膜（小单层囊泡，SUV）双层的结合显示出依赖于脂质的分子堆积以及Zn2+或Mg2+的存在。光神霉素的圆二色性（CD）性质已被用于追踪其与Zn2+和Mg2+的络合情况。在没有SUV的情况下，Mg2+和Zn2+各自能够与光神霉素形成两种不同手性的络合物：在M2+与光神霉素的低摩尔比下，得到左手构象的络合物，而在高摩尔比下形成的络合物具有右手构象。在Zn2+或Mg2+存在的情况下，光神霉素以左手构象的二聚体形式与处于凝胶相状态的SUV结合。当SUV处于液晶态时未观察到结合。
