PROMOTION OF BETA-STRUCTURE BY INTERACTION OF DIABETES ASSOCIATED POLYPEPTIDE (AMYLIN) WITH PHOSPHATIDYLCHOLINE
PROMOTION OF BETA-STRUCTURE BY INTERACTION OF DIABETES ASSOCIATED POLYPEPTIDE (AMYLIN) WITH PHOSPHATIDYLCHOLINE
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DOI：
10.1016/0167-4838(92)90411-6
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发表时间：
1992-08-21
期刊：
影响因子：
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通讯作者：
BALASUBRAMANIAM, A
中科院分区：
文献类型：
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作者：
MCLEAN, LR;BALASUBRAMANIAM, A
糖尿病相关多肽（胰淀素）与二肉豆蔻酰磷脂酰胆碱（DMPC）的相互作用通过测量浊度（在400 nm处的吸光度）和通过CD光谱的二级结构来评估。在三氟乙醇中，人胰淀素采用高度α-螺旋构象，而大鼠肽的结构较少。在水中，大鼠肽在很大程度上是无序的，而人类肽表现出α和β结构的组合。DMPC和大鼠肽的混合物对DMPC的浊度或肽的CD光谱均无影响。相比之下，人肽与DMPC的混合物形成相对透明的混合物，类似于用两亲性α-螺旋肽观察到的那些，但基于CD光谱，所采用的结构主要是β。这些数据表明，在与DMPC的混合物中存在来自人和大鼠物种的淀粉蛋白所采用的结构的根本差异，并表明这些差异可能与在大鼠肽中未观察到的人淀粉蛋白肽中淀粉样蛋白原纤维的形成有关。
The interaction of the diabetes associated polypeptide (amylin) with dimyristoylphosphatidylcholine (DMPC) was assessed by measurements of turbidity (absorbance at 400 nm) and secondary structure by CD spectroscopy. In trifluoroethanol, human amylin adopts a highly alpha-helical conformation while the rat peptide is less structured. In water, the rat peptide is largely disordered and the human peptide exhibits a combination of alpha- and beta-structures. Mixtures of DMPC and the rat peptide have no effect on either the turbidity of the DMPC or the CD spectrum of the peptide. By contrast, mixtures of the human peptide with DMPC form relatively clear mixtures similar to those observed with amphipathic alpha-helical peptides, but the structure adopted, based on the CD spectrum, is largely beta. These data demonstrate that fundamental differences in the structures adopted by amylins from human and rat species exist in mixtures with DMPC and suggest that these differences may be related to the formation of amyloid fibrils in the human amylin peptide which are not observed in the rat peptide.