Yang Y, Ke N, Liu S, Li W
Washington University School of Medicine, St. Louis, MO, United States.
New England Biolabs, Ipswich, MA, United States.
Methods Enzymol. 2017;584:309-347. doi: 10.1016/bs.mie.2016.10.032. Epub 2016 Dec 7.
The UbiA superfamily is a group of intramembrane prenyltransferases that generate lipophilic compounds essential in biological membranes. These compounds, which include various quinones, hemes, chlorophylls, and vitamin E, participate in electron transport and function as antioxidants, as well as acting as structural lipids of microbial cell walls and membranes. Prenyltransferases producing these compounds are involved in important physiological processes and human diseases. These UbiA superfamily members differ significantly in their enzymatic activities and substrate selectivities. This chapter describes examples of methods that can be used to group these intramembrane enzymes, analyze their activity, and screen and crystallize homolog proteins for structure determination. Recent structures of two archaeal homologs are compared with structures of soluble prenyltransferases to show distinct mechanisms used by the UbiA superfamily to control enzymatic activity in membranes.
泛醌合成酶A（UbiA）超家族是一组膜内异戊二烯基转移酶，可生成生物膜中必不可少的亲脂性化合物。这些化合物包括各种醌类、血红素、叶绿素和维生素E，参与电子传递，作为抗氧化剂发挥作用，同时还作为微生物细胞壁和细胞膜的结构脂质。产生这些化合物的异戊二烯基转移酶参与重要的生理过程和人类疾病。这些泛醌合成酶A超家族成员在酶活性和底物选择性上有显著差异。本章介绍了可用于对这些膜内酶进行分类、分析其活性以及筛选和结晶同源蛋白以确定其结构的方法实例。将两种古菌同源物的最新结构与可溶性异戊二烯基转移酶的结构进行比较，以展示泛醌合成酶A超家族在膜中控制酶活性所采用的不同机制。
