MOLECULAR AGGREGATION AND INDUCED NUCLEATION IN PROTEIN CRYSTAL GROWTH

蛋白质晶体生长中的分子聚集和诱导成核

基本信息

批准号：
07454068
负责人：
SATO Kiyotaka
金额：
$ 0.51万
依托单位：
HIROSHIMA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1996
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07454068/
关键词：
PROTEIN CRYSTAL GROWTH MOLECULAR AGGREGATION DYNAMIC LIGHT SCATTERING 動的先錯乱

项目摘要

This research project aimed at analyzing kinetic mechanisms in induced nucleation during the processes of protein crystal growth, mainly using dynamic light scattering techniques and crossed Nicols method. The protein molecules dealt with in the present work were lysozyme and taka-amylase.The results obtained for lysozyme crystallization using the crusaded-Nicols method are summarized in the following ; (1) the induction times were obtained by measuring the duration for the occurrence of crystals in varying supersaturating values, (2) interface energies (gamma) were evaluated from the calculation of the induction times, whose inverse values are proportional to the rates of nucleation, and supersaturation, (3) the gamma values (erg/cm^2) were 0.3 both for sitting and hanging drop methods for crystallization, (4) micro-seeding effects were found to be dependent on the sizes of seed crystals and supersaturations.The results obtained for taka-amylase crystallization are summarized in the following ; (1) diffusion constants and average particle sizes increased quite abruptly after certain induction times in supersaturated solution, (2) the occurrence of this cahnges was prompted with increasing supersaturation values, and followed by the appearance of crystals detectable by naked eyes. Therefore, one may concluded that the molecular clustering of taka-amylase was formed in prior to nucleation, as detected by the dynamic light scattering technique.These results available for the two types of proteins have shown that the pre-nucleation events are detectable, in case that the molecular weights are as large as in taka-amylase. However, more precise experiments are not possible, because the fundamental data of solubility are lacking. Thus, the solubility of taka-amylase is now measured by using a two-beam interferometric method.

该研究项目旨在分析蛋白质晶体生长过程中诱导成核中的动力学机制，主要使用动态光散射技术和跨性别的NICOLS方法。在本工作中处理的蛋白质分子是溶菌酶和塔卡 - 淀粉酶。在以下内容中总结了使用十字军烯醇法获得的溶菌酶结晶的结果。（1）通过测量晶体在不同的过饱和值中的发生持续时间获得的诱导时间，（2）从归纳时间的计算中评估界面能量（γ），其诱导时间的逆值与成核的速率成比例，并且对于态度的效应速率和静电量（3）的静电（3）是0的（3）。（4）发现微种子效应取决于种子晶体的大小和过饱和。（1）在过饱和溶液中某些诱导时间后，扩散常数和平均粒径突然增加，（2）引起该cahnges的出现，其过饱和值增加，然后通过裸眼检测到晶体的出现。因此，可以得出的结论是，在成核之前，在成核之前形成了taka-淀粉酶的分子聚类，如动态光散射技术所检测到的。这些结果可用于两种类型的蛋白质结果表明，在taka-amylase中的分子量和taka-amylase中的分子量一样大。但是，由于缺乏溶解度的基本数据，因此不可能进行更精确的实验。因此，现在使用两光束干涉方法测量taka-淀粉酶的溶解度。