Model calculations relevant to disulfide bond cleavage via electron capture influenced by positively charged groups

Journal of Physical Chemistry B

Volumn 107, Issue 48, 2003, Pages 13505-13511

  Sawicka, Agnieszka ^a,b   Skurski, Piotr ^a,b   Hudgins, Robert R ^c   Simons, Jack ^a  

^a UNIVERSITY OF UTAH   (United States)

^b UNIVERSITY OF GDA SK   (Poland)

^c YORK UNIVERSITY   (Canada)

Author keywords

[No Author keywords available]

Indexed keywords

DISSOCIATION; ELECTRON ENERGY LEVELS; ELECTRON TRAPS; ELECTRONIC STRUCTURE; HYDROGEN BONDS; MASS SPECTROMETRY; MATHEMATICAL MODELS; NEGATIVE IONS; POLYPEPTIDES; POSITIVE IONS; POTENTIAL ENERGY; PROTEINS;

ANION STATE ELECTRONICALLY STABLE; BOND RUPTURE; COULOMB POTENTIAL; DISULFIDE BOND CLEAVAGE; ELECTRON CAPTURE DISSOCIATION; POSITIVELY CHARGED GROUPS;

SULFUR COMPOUNDS;

EID: 0346947012     PISSN: 15206106     EISSN: None     Source Type: Journal    
DOI: 10.1021/jp035675d     Document Type: Article

References (24)

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8. Although not yet published, these results have been presented in public: Hudgins, R. R.; Håkansson, K.; Quinn, J. P.; Hendrickson, C. L.; Marshall, A. G. Proceedings of the 50th ASMS Conference on Mass Spectrometry and Allied Topics, Orlando, Florida, June 2-6, 2002.
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10. It is thought that ECD sources contain electrons having a distribution of kinetic energies but with very few having energies near or above 1 eV.
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13. In ref 3 an analogous process was examined in which an electron attaches to a phenyl ring whose π* orbitals have been lowered by attaching F atoms to the ring C atoms. This phenyl group was not directly attached to the protonated amine site, so electron attachment to the phenyl moiety generated such a zwitterion species.
14. -2 dependence of this potential (r being the distance to the electron), special care must be taken to preclude the attached electron from falling into this strongly attractive potential instead of into the S-S σ* orbital. These issues have caused us to defer the inclusion of dipolar potentials into our study of how Coulomb potentials can alter the probability of S-S bond cleavage via direct electron capture.
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24. We obtain this estimate by equating the intrinsic instability of the anion (0.69 eV) to the Coulomb model's prediction of stabilization 2(14.4)/ (R + 2.08/2) in eV.