1u1b

Structure of bovine pancreatic Ribonuclease A in complex with 3'-phosphothymidine (3'-5')-pyrophosphate adenosine 3'-phosphateStructure of bovine pancreatic Ribonuclease A in complex with 3'-phosphothymidine (3'-5')-pyrophosphate adenosine 3'-phosphate

Structural highlights 1u1b is a 2 chain structure with sequence from Bovin. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: Related: 1qhc Gene: RNASE1 (BOVIN) Activity: Pancreatic ribonuclease, with EC number 3.1.27.5 Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum Function [RNAS1_BOVIN] Endonuclease that catalyzes the cleavage of RNA on the 3' side of pyrimidine nucleotides. Acts on single stranded and double stranded RNA. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed Solution NMR spin-relaxation experiments were used to compare mus-ms dynamics in RNase A in the apo form and as complexed to the substrate-mimic, pTppAp. The crystal structure of the RNase A/pTppAp complex was determined and demonstrates that this ligand binds at the active site and utilizes established substrate binding sites in its interaction with RNase A. Relaxation-compensated CPMG experiments identify flexible residues in and around the active site in both the apo and pTppAp-bound enzyme. Quantitative analysis of the NMR spin-relaxation dispersion curves show that the time scale of motion in RNase A is unchanged when pTppAp binds and is similar to the time scale for the rate-determining step of the catalytic reaction. Temperature-dependent measurements provide an activation barrier for motion of 5.2 +/- 1.0 kcal/mol and 4.5 +/- 1.2 kcal/mol for the apo and pTppAp forms of RNase A, respectively. These data indicate very similar motion exists in the free and bound enzyme. Additionally, chemical shift data suggests that the magnitude of motion is also similar for these two forms and that it is likely that apo enzyme interconverts to a structure that resembles a ligand-bound form. Likewise, it appears that the bound conformation samples the apo enzyme form even when ligand is present. Taken together the data imply that RNase A is in a preexisting dynamic equilibrium between two conformations that represent the open and closed enzyme forms. These data suggest that ligand binding stabilizes the bound conformer but does not induce it. Conservation of mus-ms enzyme motions in the apo- and substrate-mimicked state.,Beach H, Cole R, Gill ML, Loria JP J Am Chem Soc. 2005 Jun 29;127(25):9167-76. PMID:15969595 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Ribonuclease Temp

spinqualitylabelsall models 1u1b, resolution 2.00Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image