title: Ribozyme speed limits.
abstract: The speed at which RNA molecules decompose is a critical determinant of many biological processes, including those directly involved in the storage and expression of genetic information. One mechanism for RNA cleavage involves internal phosphoester transfer, wherein the 2'-oxygen atom carries out an SN2-like nucleophilic attack on the adjacent phosphorus center (transesterification). In this article, we discuss fundamental principles of RNA transesterification and define a conceptual framework that can be used to assess the catalytic power of enzymes that cleave RNA. We deduce that certain ribozymes and deoxyribozymes, like their protein enzyme counterparts, can bring about enormous rate enhancements.
authors.affiliation: Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, Connecticut 06520-8103, USA.
authors.forename: Gail Mitchell
authors.initials: GM
authors.lastname: Emilsson
authors.forename: Shingo
authors.initials: S
authors.lastname: Nakamura
authors.forename: Adam
authors.initials: A
authors.lastname: Roth
authors.forename: Ronald R
authors.initials: RR
authors.lastname: Breaker
mesh_terms: D004951:Esterification; D006868:Hydrolysis; D017665:Hydroxyl Radical / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism; D012313:RNA / Q000378:metabolism*; D016337:RNA, Catalytic / Q000378:metabolism*
chemical_list: D016337:RNA, Catalytic; D017665:Hydroxyl Radical; D012313:RNA; D010100:Oxygen