An engineered ribonuclease preferring phosphorothioate RNA.
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.
Loverix
S
S
Winquist
A
A
Strömberg
R
R
Steyaert
J
J
D019943:Amino Acid Substitution / Q000235:genetics; D002384:Catalysis; D006152:Cyclic GMP / Q000031:analogs & derivatives* / Q000235:genetics; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D015202:Protein Engineering; D012313:RNA / Q000235:genetics*; D012260:Ribonucleases / Q000737:chemistry / Q000235:genetics*; D013379:Substrate Specificity / Q000235:genetics; D013873:Thionucleotides / Q000235:genetics*
D013873:Thionucleotides; C001774:guanosine 2',3'-cyclophosphorothioate; D012313:RNA; D012260:Ribonucleases; D006152:Cyclic GMP