Evaluating the stability of disulfide bridges in proteins: a torsional potential energy surface for diethyl disulfide.

ABSTRACT: Disulfide bonds formed by the oxidation of cysteine residues in proteins are the major form of intra- and inter-molecular covalent linkages in the polypeptide chain. To better understand the conformational energetics of this linkage, we have used the MP2(full)/6-31G(d) method to generate a full potential energy surface (PES) for the torsion of the model compound diethyl disulfide (DEDS) around its three critical dihedral angles (χ₂, χ₃, χ₂'). The use of ten degree increments for each of the parameters resulted in a continuous, fine-grained surface. This allowed us to accurately predict the relative stabilities of disulfide bonds in high resolution structures from the Protein Data Bank. The MP2(full) surface showed significant qualitative differences from th

SUBMITTER: Haworth NL 

PROVIDER: S-EPMC3912940 | biostudies-literature | 2007 May

REPOSITORIES: biostudies-literature