Conformational changes of the chromatin subunit.
Conformational changes of the chromatin subunit.
复制标题
染色质亚基的构象变化。
DOI：
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发表时间：
1978
影响因子：
11.1
通讯作者：
V. Schumaker
中科院分区：
文献类型：
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作者：
V. C. Gordon;C. Knobler;D. Olins;V. Schumaker
对单体染色质亚基 (v1) 作为离子强度（0.7 mM 至 100 mM KCl）函数的流体动力学研究表明存在两种盐依赖性构象转变。在大约 7.5 mM 离子强度时发生突然转变。将离子强度从 10 mM 降低到 5 mM 会导致 v1 的 s20,w 从 11.1 S 降低到 9.9 S。扩散系数 D20,w 从 3.3 降低到 2.7 X 10(-7) cm2 sec--1。在 10 mM 离子强度下与甲醛交联的 v1 在 s20,w 中不会经历类似的盐依赖性变化。在约 1 mM 离子强度下观察到另一个转变； s20,w 减小至 9.4 S，D20,w 减小至 2.2 X 10(-7) cm2 sec--1。在整个盐范围内，v1 的分子量保持相当恒定，这意味着观察到摩擦系数随盐的变化。各种流体动力学模型被认为是对观察到的摩擦系数变化的可能解释。
Hydrodynamic studies on monomer chromatin subunits (v1) as a function of ionic strength (0.7 mM to 100 mM KCl) indicate two salt-dependent conformational transitions. An abrupt transition occurs at about 7.5 mM ionic strength. Decreasing the ionic strength from 10 to 5 mM results in a decrease in s20,w of the v1 from 11.1 to 9.9 S. The diffusion coefficient D20,w decreases from 3.3 to 2.7 X 10(-7) cm2 sec--1. The v1 crosslinked with formaldehyde at 10 mM ionic strength do not undergo a similar salt-dependent change in s20,w. Another transition is observed at about 1 mM ionic strength; s20,w decreases to 9.4 S and D20,w decreases to 2.2 X 10(-7) cm2 sec--1. Throughout the entire salt range the molecular weight of the v1 remains reasonably constant, implying that salt-dependent changes in the frictional coefficient are being observed. Various hydrodynamic models are considered as possible interpretations of the observed changes in the frictional coefficient.