Juanhuix J, Bordas J, Campmany J, Svensson A, Bassford M L, Narayanan T
Laboratori Llum Sincrotró-Institut Física Altes Energies, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Barcelona, Spain.
Biophys J. 2001 Mar;80(3):1429-41. doi: 10.1016/S0006-3495(01)76115-2.
Meridional x-ray diffraction diagrams, recorded with high angular resolution, from muscles contracting at the plateau of isometric tension show that the myosin diffraction orders are clusters of peaks. These clusters are due to pronounced interference effects between the myosin diffracting units on either side of the M-line. A theoretical analysis based on the polarity of the myosin (and actin) filaments shows that it is possible to extract phase information from which the axial disposition of the myosin heads can be determined. The results show that each head in a crown pair has a distinct structural disposition. It appears that only one of the heads in the pair stereospecifically interacts with the thin filament at any one time.
用高角分辨率记录的等长张力平台期收缩肌肉的子午线X射线衍射图表明，肌球蛋白衍射级是峰簇。这些簇是由于M线两侧的肌球蛋白衍射单元之间明显的干涉效应所致。基于肌球蛋白（和肌动蛋白）丝极性的理论分析表明，可以提取相位信息，据此可确定肌球蛋白头部的轴向排列。结果表明，冠对中的每个头部都有独特的结构排列。似乎该对中的只有一个头部在任何时候都与细肌丝发生立体特异性相互作用。
