An engineered ribonuclease preferring phosphorothioate RNA.

TitleAn engineered ribonuclease preferring phosphorothioate RNA.
Publication TypeJournal Article
Year of Publication1998
AuthorsLoverix, S., A. Winquist, R. Strömberg, and J. Steyaert
JournalNat Struct Biol
Volume5
Issue5
Pagination365-8
Date Published1998 May
ISSN1072-8368
KeywordsAmino Acid Substitution, Catalysis, Cyclic GMP, Models, Molecular, Mutagenesis, Site-Directed, Protein Engineering, Ribonucleases, RNA, Substrate Specificity, Thionucleotides
Abstract

We used mutants of RNase T1 and the Rp isomer of a thiosubstituted substrate to determine stereospecific thioeffects on catalysis. The analysis reveals subtle structural and functional changes in the intermolecular transition state interactions. Tyr 38 contributes to catalysis through a hydrogen bond with the pro-Rp oxygen. Y38F RNase T1 prefers the Rp thiosubstituted analog over the natural phosphodiester substrate that is favored by the wild type enzyme.

Alternate JournalNat. Struct. Biol.
PubMed ID9586998