Ghent University Academic Bibliography

Advanced

Solved?: the reductive radiation chemistry of alanine

Ewald Pauwels UGent, Hendrik De Cooman, Michel Waroquier UGent, Eli O Hole and Einar Sagstuen (2014) PHYSICAL CHEMISTRY CHEMICAL PHYSICS. 16(6). p.2475-2482
abstract
The structural changes throughout the entire reductive radiation-induced pathway of L-alpha-alanine are solved on an atomistic level with the aid of periodic DFT and nudged elastic band (NEB) simulations. This yields unprecedented information on the conformational changes taking place, including the protonation state of the carboxyl group in the "unstable'' and "stable'' alanine radicals and the internal transformation converting these two radical variants at temperatures above 220 K. The structures of all stable radicals were verified by calculating EPR properties and comparing those with experimental data. The variation of the energy throughout the full radiochemical process provides crucial insight into the reason why these structural changes and rearrangements occur. Starting from electron capture, the excess electron quickly localizes on the carbon of a carboxyl group, which pyramidalizes and receives a proton from the amino group of a neighboring alanine molecule, forming a first stable radical species (up to 150 K). In the temperature interval 150-220 K, this radical deaminates and deprotonates at the carboxyl group, the detached amino group undergoes inversion and its methyl group sustains an internal rotation. This yields the so-called "unstable alanine radical''. Above 220 K, triggered by the attachment of an additional proton on the detached amino group, the radical then undergoes an internal rotation in the reverse direction, giving rise to the "stable alanine radical'', which is the final stage in the reductive radiation-induced decay of alanine.
Please use this url to cite or link to this publication:
author
organization
year
type
journalArticle (original)
publication status
published
subject
keyword
IRRADIATED SINGLE-CRYSTALS, MINIMUM ENERGY PATHS, SPACE GAUSSIAN PSEUDOPOTENTIALS, ELECTRON SPIN RESONANCE, :L-ALPHA-ALANINE, HYPERFINE COUPLING-CONSTANTS, DENSITY-FUNCTIONAL CALCULATIONS, ELASTIC BAND METHOD, LOW-TEMPERATURES, PARAMAGNETIC-RESONANCE
journal title
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
Phys. Chem. Chem. Phys.
volume
16
issue
6
pages
2475 - 2482
Web of Science type
Article
Web of Science id
000329926700034
JCR category
PHYSICS, ATOMIC, MOLECULAR & CHEMICAL
JCR impact factor
4.493 (2014)
JCR rank
6/34 (2014)
JCR quartile
1 (2014)
ISSN
1463-9076
DOI
10.1039/c3cp54441a
project
HPC-UGent: the central High Performance Computing infrastructure of Ghent University
language
English
UGent publication?
yes
classification
A1
copyright statement
I have transferred the copyright for this publication to the publisher
id
4290162
handle
http://hdl.handle.net/1854/LU-4290162
date created
2014-02-13 10:50:01
date last changed
2016-12-19 15:46:06
@article{4290162,
  abstract     = {The structural changes throughout the entire reductive radiation-induced pathway of L-alpha-alanine are solved on an atomistic level with the aid of periodic DFT and nudged elastic band (NEB) simulations. This yields unprecedented information on the conformational changes taking place, including the protonation state of the carboxyl group in the {\textacutedbl}unstable'' and {\textacutedbl}stable'' alanine radicals and the internal transformation converting these two radical variants at temperatures above 220 K. The structures of all stable radicals were verified by calculating EPR properties and comparing those with experimental data. The variation of the energy throughout the full radiochemical process provides crucial insight into the reason why these structural changes and rearrangements occur. Starting from electron capture, the excess electron quickly localizes on the carbon of a carboxyl group, which pyramidalizes and receives a proton from the amino group of a neighboring alanine molecule, forming a first stable radical species (up to 150 K). In the temperature interval 150-220 K, this radical deaminates and deprotonates at the carboxyl group, the detached amino group undergoes inversion and its methyl group sustains an internal rotation. This yields the so-called {\textacutedbl}unstable alanine radical''. Above 220 K, triggered by the attachment of an additional proton on the detached amino group, the radical then undergoes an internal rotation in the reverse direction, giving rise to the {\textacutedbl}stable alanine radical'', which is the final stage in the reductive radiation-induced decay of alanine.},
  author       = {Pauwels, Ewald and De Cooman, Hendrik and Waroquier, Michel and Hole, Eli O and Sagstuen, Einar},
  issn         = {1463-9076},
  journal      = {PHYSICAL CHEMISTRY CHEMICAL PHYSICS},
  keyword      = {IRRADIATED SINGLE-CRYSTALS,MINIMUM ENERGY PATHS,SPACE GAUSSIAN PSEUDOPOTENTIALS,ELECTRON SPIN RESONANCE,:L-ALPHA-ALANINE,HYPERFINE COUPLING-CONSTANTS,DENSITY-FUNCTIONAL CALCULATIONS,ELASTIC BAND METHOD,LOW-TEMPERATURES,PARAMAGNETIC-RESONANCE},
  language     = {eng},
  number       = {6},
  pages        = {2475--2482},
  title        = {Solved?: the reductive radiation chemistry of alanine},
  url          = {http://dx.doi.org/10.1039/c3cp54441a},
  volume       = {16},
  year         = {2014},
}

Chicago
Pauwels, Ewald, Hendrik De Cooman, Michel Waroquier, Eli O Hole, and Einar Sagstuen. 2014. “Solved?: The Reductive Radiation Chemistry of Alanine.” Physical Chemistry Chemical Physics 16 (6): 2475–2482.
APA
Pauwels, Ewald, De Cooman, H., Waroquier, M., Hole, E. O., & Sagstuen, E. (2014). Solved?: the reductive radiation chemistry of alanine. PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 16(6), 2475–2482.
Vancouver
1.
Pauwels E, De Cooman H, Waroquier M, Hole EO, Sagstuen E. Solved?: the reductive radiation chemistry of alanine. PHYSICAL CHEMISTRY CHEMICAL PHYSICS. 2014;16(6):2475–82.
MLA
Pauwels, Ewald, Hendrik De Cooman, Michel Waroquier, et al. “Solved?: The Reductive Radiation Chemistry of Alanine.” PHYSICAL CHEMISTRY CHEMICAL PHYSICS 16.6 (2014): 2475–2482. Print.