Low-Temperature Heat Capacity and Glassy Behavior of Lysozyme Crystal†
Low-Temperature Heat Capacity and Glassy Behavior of Lysozyme Crystal†
复制标题
溶菌酶晶体的低温热容和玻璃态行为†
DOI：
10.1021/jp0007686
复制
发表时间：
2000
影响因子：
3.3
通讯作者：
H. Suga
中科院分区：
文献类型：
--
作者：
Y. Miyazaki;and Takasuke Matsuo;H. Suga
在8 ~ 300 K温度范围内，测定了不同含水量的溶菌酶晶体的热容。一个广泛的玻璃化转变，观察到在约150 K的晶体与超过24.0重量%的水含量。这些晶体还表现出自发的放热效应，这是由于晶体中所含的过冷水的结晶和高于玻璃化转变温度的水的熔融过程。含有13.6和7.4重量%的水的晶体只引起在165和218 K的玻璃化转变，分别。完全干燥的晶体在高达300 K的温度下没有显示出热异常。根据结晶水的溶解度估算了可冻结水和不可冻结水的量。水含量的玻璃化转变温度和过量热容的大小的依赖性表明，所观察到的玻璃化转变产生的合作运动之间的段的…
Heat capacities of tetragonal hen egg-white lysozyme crystals containing different amounts of water have been measured in the temperature region between 8 and 300 K. A broad glass transition was observed at about 150 K for the crystals with more than 24.0 wt % water content. These crystals also exhibited a spontaneous exothermic effect due to crystallization of the supercooled water contained in the crystals and melting process of the water above the glass transition temperature. The crystals containing 13.6 and 7.4 wt % of water gave rise to only a glass transition at 165 and 218 K, respectively. The fully dried crystal showed no thermal anomaly in the temperature up to 300 K. The amounts of the freezable and unfreezable water were estimated from the enthalpies of fusion of the crystal water. The water content dependence of the glass transition temperature and the magnitude of the excess heat capacity suggest that the observed glass transition arises from the cooperative motion between the segments of th...