Gordeliy V I, Cherezov V G, Tugan-Baranovskaya A D, Yagujinskiy L S
Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Moscow District, Russia.
Biochem Mol Biol Int. 1996 Mar;38(3):485-91.
This paper presents experimental data on the determination of the thickness of thylakoid membranes by small-angle neutron scattering. The thylakoids were isolated from spinach chloroplasts. The partial volume of proteins and lipids in the "washed" and "unwashed" membranes was estimated. It is shown that the thickness of thylakoid membranes, measured with this techniques depends on the way the membranes were separated. When isolated thylakoids by the standard method, the membrane thickness amounted to 75 A but if the extracted thylakoids were additionally washed with the isolation medium, the measured thickness was 50 A. In this case a significant decrease in the protein partial volume of the membrane was observed. The obtained results make it possible to explain numerous data on X-ray and small-angle neutron scattering by thylakoid membranes of different origins, proceeding from the assumption that all these membranes have a unified structure and consist of a stable core with a thickness of about 50 A, and layers of peripheral, weakly bound proteins with a thickness which may depends on the nature of the object under investigation and extracting conditions.
本文介绍了通过小角中子散射测定类囊体膜厚度的实验数据。类囊体是从菠菜叶绿体中分离出来的。估算了“洗涤过的”和“未洗涤过的”膜中蛋白质和脂质的偏摩尔体积。结果表明，用该技术测量的类囊体膜厚度取决于膜的分离方式。采用标准方法分离类囊体时，膜厚度为75埃，但如果用分离介质对提取的类囊体进行额外洗涤，测量厚度为50埃。在这种情况下，观察到膜的蛋白质偏摩尔体积显著下降。所得结果使得从所有这些膜具有统一结构且由厚度约为50埃的稳定核心以及厚度可能取决于研究对象性质和提取条件的外周弱结合蛋白质层组成这一假设出发，解释不同来源类囊体膜的大量X射线和小角中子散射数据成为可能。
