Contraction-Induced Changes in Hydrogen Bonding of Muscle Hydration Water.
Contraction-Induced Changes in Hydrogen Bonding of Muscle Hydration Water.
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DOI：
10.1021/jz5000879
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发表时间：
2014-03-20
期刊：
影响因子：
--
通讯作者：
Pollack GH
中科院分区：
文献类型：
--
作者：
Yoo H;Nagornyak E;Das R;Wexler AD;Pollack GH
蛋白质-水相互作用在蛋白质动力学及其功能中起着至关重要的作用。为了以高空间分辨率研究水和蛋白质的化学环境，使用同步辐射傅里叶变换红外（SR-FTIR）光谱显微镜来探测骨骼肌肌原纤维。观察 OH 拉伸带表明，松弛的肌原纤维内部的水广泛氢键结合，几乎没有或没有游离 OH。在用单个分离的肌原纤维获得的高分辨率测量中，与 I 带区域相比，肌节中心区域的吸水峰相对较高，这意味着粗肌丝比细肌丝具有更高的水合能力。当样本被激活时，OH弹力带的变化表明肌肉水有显着的脱氢键合；与松弛的肌原纤维相比，~3480 cm-1 处的吸收增加表明了这一点。这些收缩引起的水变化伴随着酰胺 I (C=O) 峰的分裂，这意味着肌肉蛋白从 α 螺旋转变为富含 β 折叠的结构。因此，肌肉收缩的特点是肌肉-蛋白质复合物失去秩序，并伴有水合水的破坏。这些发现为肌肉收缩和运动蛋白动力学的分子机制提供了新的线索。
Protein–water interaction plays a crucial role in protein dynamics and hence function. To study the chemical environment of water and proteins with high spatial resolution, synchrotron radiation-Fourier transform infrared (SR-FTIR) spectromicroscopy was used to probe skeletal muscle myofibrils. Observing the OH stretch band showed that water inside of relaxed myofibrils is extensively hydrogen-bonded with little or no free OH. In higher-resolution measurements obtained with single isolated myofibrils, the water absorption peaks were relatively higher within the center region of the sarcomere compared to those in the I-band region, implying higher hydration capacity of thick filaments compared to the thin filaments. When specimens were activated, changes in the OH stretch band showed significant dehydrogen bonding of muscle water; this was indicated by increased absorption at ∼3480 cm–1 compared to relaxed myofibrils. These contraction-induced changes in water were accompanied by splitting of the amide I (C=O) peak, implying that muscle proteins transition from α-helix to β-sheet-rich structures. Hence, muscle contraction can be characterized by a loss of order in the muscle–protein complex, accompanied by a destructuring of hydration water. The findings shed fresh light on the molecular mechanism of muscle contraction and motor protein dynamics.
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影响因子：
5.5
作者：
FORD, LE;HUXLEY, AF;SIMMONS, RM
通讯作者：
SIMMONS, RM
DOI：
10.1083/jcb.11.1.95
发表时间：
1961-10
期刊：
The Journal of biophysical and biochemical cytology
影响因子：
--
作者：
CARLSEN F;KNAPPEIS GG;BUCHTHAL F
通讯作者：
BUCHTHAL F
影响因子：
7.4
作者：
Holman, Hoi-Ying N.;Bechtel, Hans A.;Martin, Michael C.
通讯作者：
Martin, Michael C.
影响因子：
3.9
作者：
Goertz, Matthew P.;Houston, J. E.;Zhu, X-Y.
通讯作者：
Zhu, X-Y.
影响因子：
2.9
作者：
BYLER, DM;SUSI, H
通讯作者：
SUSI, H