title: Continuous in vitro evolution of a ribozyme that catalyzes three successive nucleotidyl addition reactions.
abstract: Variants of the class I ligase ribozyme, which catalyzes joining of the 3' end of a template bound oligonucleotide to its own 5' end, have been made to evolve in a continuous manner by a simple serial transfer procedure that can be carried out indefinitely. This process was expanded to allow the evolution of ribozymes that catalyze three successive nucleotidyl addition reactions, two template-directed mononucleotide additions followed by RNA ligation. During the development of this behavior, a population of ribozymes was maintained against an overall dilution of more than 10(406). The resulting ribozymes were capable of catalyzing the three-step reaction pathway, with nucleotide addition occurring in either a 5'-->3' or a 3'-->5' direction. This purely chemical system provides a functional model of a multi-step reaction pathway that is undergoing Darwinian evolution.
authors.affiliation: Department of Chemistry and The Skaggs Institute for Chemical Biology, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
authors.forename: Kathleen E
authors.initials: KE
authors.lastname: McGinness
authors.forename: Martin C
authors.initials: MC
authors.lastname: Wright
authors.forename: Gerald F
authors.initials: GF
authors.lastname: Joyce
mesh_terms: D001483:Base Sequence; D002384:Catalysis; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism; D019143:Evolution, Molecular; D007700:Kinetics; D008969:Molecular Sequence Data; D016296:Mutagenesis; D009690:Nucleic Acid Conformation; D009711:Nucleotides / Q000737:chemistry* / Q000378:metabolism*; D010761:Phosphorus Radioisotopes; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic / Q000235:genetics; D011130:RNA Ligase (ATP) / Q000378:metabolism; D016337:RNA, Catalytic / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D017423:Sequence Analysis, RNA; D013379:Substrate Specificity; D014764:Viral Proteins
chemical_list: D009711:Nucleotides; D010761:Phosphorus Radioisotopes; D016337:RNA, Catalytic; D014764:Viral Proteins; C062210:bacteriophage T7 RNA polymerase; D012321:DNA-Directed RNA Polymerases; D011130:RNA Ligase (ATP)