Comparison of fully optimized α- and 310-helices with extended β-strands. An ONIOM density functional theory study
Comparison of fully optimized α- and 310-helices with extended β-strands. An ONIOM density functional theory study
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DOI：
10.1021/ja048831i
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发表时间：
2004-11-03
影响因子：
15
通讯作者：
Dannenberg, JJ
中科院分区：
文献类型：
--
作者：
Wieczorek, R;Dannenberg, JJ
我们使用完全优化的混合DFT/AM 1计算，比较了N值为2至18的封端聚丙氨酸乙酰基（ala）（N）NH 2的β链、α螺旋和3（10）螺旋的结构和能量。非成对加性协同性是从两种类型的螺旋的相对能量，螺旋应变，偶极矩，和H-键长的变化，但特别是对于α-螺旋。虽然气相3（10）-螺旋对于小聚丙氨酸更稳定，主要是由于额外的H-键，但随着聚丙氨酸尺寸的增加，α-螺旋变得相对更稳定。
We compare the structures and energies of beta-strands, alpha-helices, and 3(10)-helices for capped polyalanines, acetyl(ala)(N)NH2, for values of N from 2 to 18, using completely optimized mixed DFT/AM1 calculations. Non-pairwise additive cooperativity is manifest from the variation of the relative energies, helical strain, dipole moments, and H-bond lengths of both types of helices, but especially for the alpha-helices. While the gas-phase 3(10)-helices are more stable for small polyalanines, largely due to the additional H-bond, the alpha-helices become relatively more stable as the polyalanines increase in size.