Preissner R, Egner U, Saenger W
Institut für Kristallographie, Freie Universität Berlin, Germany.
FEBS Lett. 1991 Aug 19;288(1-2):192-6. doi: 10.1016/0014-5793(91)81032-4.
Analysis of 13 high-resolution protein X-ray crystal structures shows that 1204 (24%) of all the 4974 hydrogen bonds are of the bifurcated three-center type with the donor X-H opposing two acceptors A1, A2. They occur systematically in alpha-helices where 90% of the hydrogen bonds are of this type; the major component is (n + 4)N-H ... O = C(n) as expected for a 3.6(13) alpha-helix, and the minor component is (n + 4)N-H ... O = C(n + 1), as observed in 3(10) helices; distortions at the C-termini of alpha-helices are stabilized by three-center bonds. In beta-sheets 40% of the hydrogen bonds are three-centered. The frequent occurrence of three-center hydrogen bonds suggests that they should not be neglected in protein structural studies.
对13个高分辨率蛋白质X射线晶体结构的分析表明，在所有4974个氢键中，有1204个（24%）是分叉的三中心类型，供体X-H与两个受体A1、A2相对。它们系统地出现在α螺旋中，其中90%的氢键属于这种类型；主要成分是（n + 4）N-H...O = C（n），这是3.6（13）α螺旋所预期的，次要成分是（n + 4）N-H...O = C（n + 1），如在3（10）螺旋中所观察到的；α螺旋C末端的扭曲通过三中心键得以稳定。在β折叠中，40%的氢键是三中心的。三中心氢键的频繁出现表明，在蛋白质结构研究中不应忽视它们。
