Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences , 32 West Seventh Avenue, Tianjin Airport Economic Area , Tianjin 300308 , China.
State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology , Shanghai Jiao Tong University , Shanghai 200240 , China.
Chem Rev. 2019 Feb 13;119(3):1626-1665. doi: 10.1021/acs.chemrev.8b00290. Epub 2019 Jan 30.
The term B-factor, sometimes called the Debye-Waller factor, temperature factor, or atomic displacement parameter, is used in protein crystallography to describe the attenuation of X-ray or neutron scattering caused by thermal motion. This review begins with analyses of early protein studies which suggested that B-factors, available from the Protein Data Bank, can be used to identify the flexibility of atoms, side chains, or even whole regions. This requires a technique for obtaining normalized B-factors. Since then the exploitation of B-factors has been extensively elaborated and applied in a variety of studies with quite different goals, all having in common the identification and interpretation of rigidity, flexibility, and/or internal motion which are crucial in enzymes and in proteins in general. Importantly, this review includes a discussion of limitations and possible pitfalls when using B-factors. A second research area, which likewise exploits B-factors, is also reviewed, namely, the development of the so-called B-FIT-directed evolution method for increasing the thermostability of enzymes as catalysts in organic chemistry and biotechnology. In both research areas, a maximum of structural and mechanistic insights is gained when B-factor analyses are combined with other experimental and computational techniques.
术语 B 因子，有时也称为德拜-沃勒因子、温度因子或原子位移参数，在蛋白质晶体学中用于描述热运动引起的 X 射线或中子散射的衰减。这篇综述首先分析了早期的蛋白质研究，这些研究表明，可从蛋白质数据库中获得的 B 因子可用于识别原子、侧链甚至整个区域的柔韧性。这需要一种获取归一化 B 因子的技术。从那时起，B 因子的利用已经在各种具有不同目标的研究中得到了广泛的阐述和应用，所有这些研究都有一个共同的目标，即识别和解释刚性、柔性和/或内部运动，这些在酶和一般蛋白质中至关重要。重要的是，本综述还讨论了在使用 B 因子时的局限性和可能的陷阱。第二个同样利用 B 因子的研究领域也进行了综述，即所谓的 B-FIT 定向进化方法的发展，该方法用于提高酶作为有机化学和生物技术中催化剂的热稳定性。在这两个研究领域中，当 B 因子分析与其他实验和计算技术结合使用时，可以获得最大的结构和机制见解。
