title: Three-dimensional structure of the ribonuclease T1 X 3'-guanylic acid complex at 2.6 A resolution.
abstract: The mother enzyme of RNase T1 was co-crystallized with its natural product, 3'-GMP at pH 4.0. The X-ray structure of this complex was refined with 2432 reflections in the 5.4-2.6 A range using a stereochemical restrained method (conventional R = 27.4%). The overall polypeptide chain folding is very similar in the secondary structure elements to the RNase T1 in the complex with 2'-GMP crystallized also at pH 4.0, but larger conformational changes occur in the loop regions. The base recognition scheme is identical in both complexes but in RNase T1 X 3'-GMP, the ribose phosphate is not seen in the electron density, probably due to static disorder.
authors.forename: S
authors.initials: S
authors.lastname: Sugio
authors.forename: K
authors.initials: K
authors.lastname: Oka
authors.forename: H
authors.initials: H
authors.lastname: Ohishi
authors.forename: K
authors.initials: K
authors.lastname: Tomita
authors.forename: W
authors.initials: W
authors.lastname: Saenger
mesh_terms: D055598:Chemical Phenomena; D002627:Chemistry, Physical; D004722:Endoribonucleases / Q000378:metabolism*; D006150:Guanine Nucleotides / Q000378:metabolism*; D006157:Guanosine Monophosphate / Q000378:metabolism*; D008958:Models, Molecular; D011487:Protein Conformation; D006163:Ribonuclease T1 / Q000378:metabolism*; D014961:X-Ray Diffraction
chemical_list: D006150:Guanine Nucleotides; D006157:Guanosine Monophosphate; D004722:Endoribonucleases; D006163:Ribonuclease T1