小角X射线散射实验中蛋白质溶液的辐照损伤及防护方法  

Irradiation Damage and Protection Strategies of Protein Solution in SAXS Experiments

作　　者：邢雪青[1] 刘超 默广[1] 史颖 吴忠华[1] XING Xue-Qing;LIU Chao;MO Guang;SHI Ying;WU Zhong-Hua(Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China;Advanced Manufacturing Institute of Polymer Industry,Shenyang University of Chemical Technology,Shenyang 110142,China)

机构地区：[1]中国科学院高能物理研究所,北京100049 [2]沈阳化工大学高分子产业高端制造研究院,沈阳110142

出　　处：《生物化学与生物物理进展》2022年第9期1703-1718,共16页Progress In Biochemistry and Biophysics

基　　金：国家重点研发计划(2017YFA0403100,2017YFA0403000)资助项目。

摘　　要：随着同步辐射光源(尤其是目前快速发展的第四代同步辐射光源)技术的进步,可用于实验的辐射通量越来越高,实验样品(特别是蛋白质等生物大分子样品)受到的辐照损伤也越来越严重。在全球现有的同步辐射装置上,蛋白质等生物大分子溶液专用小角X射线散射(SAXS)实验站的光子通量基本上都在1013cps量级。在如此高的通量下,蛋白质等生物大分子溶液样品在实验测量中受到的辐照损伤极其严重。如果没有有效的辐照防护措施,蛋白质溶液样品在毫秒级辐照时间内便会辐照损伤,导致不能获取有效的实验数据。辐照损伤严重制约了SAXS实验技术在蛋白质溶液样品方面的应用。因而,认识蛋白质溶液样品辐照损伤的产生机理、影响因素、判断标准,以及有效降低辐照损伤程度、延缓辐照损伤产生时间的方法,对于蛋白质等生物大分子溶液的散射实验具有重要的指导意义。本文在简要概述生物大分子溶液样品辐照损伤产生机理、影响因素、辐照剂量等基本概念的基础上,重点综述了同步辐射SAXS实验中辐照损伤的判断标准和防护措施。此外,本文还对比了各种防护措施的优缺点,讨论了在建HEPS新光源中SAXS束线可用的散射数据采集时间,指出辐照损伤防护剂是有价值的研究方向。With the development of synchrotron radiation photon sources(especially the fourth generation of synchrotron radiation light sources),the radiation flux available for experiments is getting higher and higher,and the radiation damage of experimental samples(especially biological macromolecules such as proteins)is getting more and more serious.In the existing synchrotron radiation facilities around the world,the photon flux of SAXS experimental station for protein and other biological macromolecule solutions is basically in the order of 1013 cps.At such a high flux,the radiation damage of protein and other biological macromolecule solution samples is very serious in experimental measurement.If there is no effective radiation protection measures,protein solution samples will be damaged by irradiation within the millisecond irradiation time,resulting in the inability to obtain effective experimental data.Radiation damage severely restricts the application of SAXS in protein solution samples.Therefore,it is of great guiding significance for the scattering experiments of protein and other biomolecular solutions to understand the generation mechanism,influencing factors and judgment criteria of radiation damage of protein solution samples,and to effectively reduce the degree of radiation damage or delay the generation time of radiation damage.On the basis of a brief introduction to the basic concepts of irradiation damage mechanism,influencing factors,and irradiation dose of biomolecular solution samples,this paper summarizes the criteria and protective measures of radiation damage in synchrotron radiation SAXS experiments.In addition,this paper also compares the advantages and disadvantages of various protective measures,discusses the available acquisition time of SAXS-beamline scattering data on the high energy photon source(HEPS)under construction,and points out that the protective agents of irradiation damage are a valuable research direction.

关 键 词：同步辐射小角散射 蛋白质溶液 辐照损伤 防护方法 

分 类 号：Q691[生物学—生物物理学]