title: Biologically important reactions catalyzed by RNA molecules.
abstract: The last few years have seen a considerable increase in our understanding of catalysis by naturally occurring RNA molecules called ribozymes. The biological functions of RNA molecules depend upon their adoption of appropriate three-dimensional structures. The structure of RNA has a very important electrostatic component, which results from the presence of charged phosphodiester bonds. Metal ions are usually required to stabilize the folded structures and/or catalysis. Some ribozymes utilize metal ions as catalysts, whereas others use the ions to maintain appropriate three-dimensional structures. In the latter case, the correct folding of the RNA structures can perturb the pKa values of the nucleotide(s) within a catalytic pocket such that they act as general acid/bases catalysts.
mesh_terms: D001483:Base Sequence; D002384:Catalysis; D003698:Hepatitis Delta Virus / Q000201:enzymology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008670:Metals / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D008956:Models, Chemical; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D009841:Oligonucleotides / Q000737:chemistry; D010452:Peptide Biosynthesis; D012313:RNA / Q000737:chemistry* / Q000378:metabolism; D012326:RNA Splicing; D016337:RNA, Catalytic / Q000737:chemistry / Q000378:metabolism; D013816:Thermodynamics
chemical_list: D008670:Metals; D009841:Oligonucleotides; D016337:RNA, Catalytic; D012313:RNA