Conformational preferences and pKa value of selenocysteine residue

  title={Conformational preferences and pKa value of selenocysteine residue},
  author={Byung Jin Byun and Young Kee Kang},
The conformational preferences of the L‐selenocysteine (Sec) dipeptides with selenol and selenolate groups (Ac‐Sec‐NHMe and Ac‐Sec−‐NHMe, respectively) and the apparent (i.e., macroscopic) pKa value of the Sec residue have been studied using the dispersion‐corrected density functionals M06‐2X and B2PLYP‐D with the implicit solvation method in the gas phase and in water. In the gas phase, the backbone‐to‐backbone and/or side chain‐to‐backbone hydrogen bonds are found to contribute in stabilizing… 

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  • Y. Kang
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    The journal of physical chemistry. B
  • 2006
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Co2+ binding cysteine and selenocysteine: a DFT study.

From the present calculations, a metal-induced thiol deprotonation as observed in gas-phase experiments is explained, and a very small difference in cobalt binding affinity is found, thus justifying the use of this substitution in X-ray absorption experiments done on biomolecules containing cysteine metal binding pockets.

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  • L. Moroder
  • Chemistry, Biology
    Journal of peptide science : an official publication of the European Peptide Society
  • 2005
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Density functional methods have been employed to characterize the gas phase conformations of selenocysteine. The 33 stable conformers of selenocysteine have been located on the potential energy

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Three approaches of computational chemistry were used to investigate the redox cycle of bovine erythrocyte glutathione peroxidase from class 1 and new atomistic details for a generally accepted mechanism of GPx1 are proposed.