Rapid and simple ribozymic aminoacylation using three conserved nucleotides.

ABSTRACT: Selection-amplification finds new RNA enzymes (ribozymes) among randomized RNAs with flanking unvaried sequences (primer complements). Precise removal of 3'-primer before reaction selected aminoacylation from PheAMP in three cycles, yielding active RNAs (k(cat) = 12-20 min(-1)) using only three conserved nucleotides, acting independently of divalent ions. This unusually simple RNA active site encouraged study of the reaction via molecular mechanics-based free energy minimization. On this basis, we suggest a chemical path for RNA-catalyzed transaminoacylation. Site modeling also predicted new features, L-stereoselectivity, 2'-regioselectivity, independence of amino acid side chain, and phosphorylated activating group, that were subsequently verified. The same selection also showed that RNA

SUBMITTER: Chumachenko NV 

PROVIDER: S-EPMC2750092 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature