2op2
From Proteopedia
Crystal structure of RNase double-mutant V43C R85C with extra disulphide bond
Overview
A previously introduced kinetic-rate constant (k/k(0)) method, where k and k(0) are the folding (unfolding) rate constants in the mutant and the wild-type forms, respectively, of a protein, has been applied to obtain qualitative information about structure in the transition state ensemble (TSE) of bovine pancreatic ribonuclease A (RNase A), which contains four native disulfide bonds. The method compares the folding (unfolding) kinetics of RNase A, with and without a covalent crosslink and tests whether the crosslinked residues are associated in the folding (unfolding) transition state (TS) of the noncrosslinked version. To confirm that the fifth disulfide bond has not introduced a significant structural perturbation, we solved the crystal structure of the V43C-R85C mutant to 1.6 A resolution. Our findings suggest that residues Val43 and Arg85 are not associated, and that residues Ala4 and Val118 may form nonnative contacts, in the folding (unfolding) TSE of RNase A.
About this Structure
2OP2 is a Single protein structure of sequence from Bos taurus. Full crystallographic information is available from OCA.
Reference
Implementation of a k/k(0) method to identify long-range structure in transition states during conformational folding/unfolding of proteins., Pradeep L, Kurinov I, Ealick SE, Scheraga HA, Structure. 2007 Oct;15(10):1178-89. PMID:17937908 Page seeded by OCA on Sun May 4 11:21:49 2008