The RNA modification database: 1999 update

The RNA Modification Database (http://medlib.med. utah,edu/RNAmods/) provid es a comprehensive listing of naturally modified nucleosides in RNA. Each f ile includes: chemical structure; common name and symbol; type(s) of RNA in which found and corresponding phylogenetic distribution; Chemical Abstract s registry number and index name; and initial literature citations for stru cture characterization and chemical synthesis. New features include capabil ity to search database files by name or substructural features, modificatio ns in tmRNA, and links to related data and sites.