Hydrolysis of a slow cyclic thiophosphate substrate of RNase T1 analyzed by time-resolved crystallography

Nat Struct Biol. 1998 Apr;5(4):280-3. doi: 10.1038/nsb0498-280.

Abstract

Here we present a time-resolved crystallographic analysis of the hydrolysis of exo (Sp) guanosine 2',3'-cyclophosphorothioate by RNase T1. The use of a slow substrate and fast crystallization methods made it possible to perform the study with conventional data-collection techniques. The results support the idea that the hydrolysis reaction proceeds through a mechanism that is the inverse of the transesterification reaction. In addition, the structures provide an explanation for the differential behavior of RNase T1 towards exo- and endo-cyclic thiophosphates.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aspergillus oryzae / enzymology
  • Binding Sites
  • Computer Simulation
  • Crystallography, X-Ray / methods
  • Cyclic GMP / analogs & derivatives*
  • Cyclic GMP / chemistry
  • Cyclic GMP / metabolism
  • Hydrolysis
  • Models, Molecular
  • Molecular Conformation
  • Molecular Sequence Data
  • Protein Conformation
  • Ribonuclease T1 / chemistry*
  • Ribonuclease T1 / metabolism*
  • Substrate Specificity
  • Thionucleotides / chemistry
  • Thionucleotides / metabolism*
  • Time Factors

Substances

  • Thionucleotides
  • guanosine 2',3'-cyclophosphorothioate
  • Ribonuclease T1
  • Cyclic GMP

Associated data

  • PDB/1GSP
  • PDB/2GSP
  • PDB/3GSP
  • PDB/4GSP
  • PDB/5GSP
  • PDB/6GSP
  • PDB/7GSP