TITLE:
Chiral Recognition of Dansyl Derivatives with an Amino Acid-Based Molecular Micelle: A Molecular Dynamics Investigation
AUTHORS:
Mauro Garcia, Nathan Black, Eugene Billiot, Fereshteh Billiot, Kevin F. Morris, Yayin Fang
KEYWORDS:
Amino Acid Based Molecular Micelles, Molecular Modeling, Computational Chemistry, Chiral Recognition
JOURNAL NAME:
Open Journal of Physical Chemistry,
Vol.11 No.2,
May
26,
2021
ABSTRACT: In this study, the chiral separation mechanisms of Dansyl amino acids,
including Dansyl-Leucine (Dans-Leu), Dansyl-Norleucine (Dans-Nor), Dansyl-Tryptophan
(Dans-Trp) and Dansyl-Phenylalanine (Dans-Phe) binding to poly-sodium N-undecanoyl-(L)-Leucylvalinate,
poly (SULV), were investigated using molecular dynamics simulations. Micellar
electrokinetic chromatography (MEKC) has previously shown that when separating
the enantiomers of these aforementioned Dansyl amino acids, the L-enantiomers bind
stronger to poly (SULV) than the D-enantiomers. This study aims to investigate
the molecular interactions that govern chiral recognition in these systems
using computational methods. This study reveals that the
computationally-calculated binding free energy values for Dansyl enantiomers
binding to poly (SULV) are in agreement with the enantiomeric order produced in
experimental MEKC studies. The L-enantiomers of Dans-Leu, Dans-Nor, Dans-Trp,
and Dans-Phe binding to their preferred binding pockets in poly (SULV) yielded
binding free energy values of -21.8938, -22.1763, -21.3329 and -13.3349 kJ·mol-1, respectively. The D-enantiomers
of Dans-Leu, Dans-Nor, Dans-Trp, and Dans-Phe binding to their preferred
binding pockets in poly (SULV) yielded binding free energy values of -14.5811, -15.9457, -13.6408, and -12.0959 kJ·mol-1, respectively. Furthermore, hydrogen bonding
analyses were used to investigate and elucidate the molecular interactions that govern
chiral recognition in these molecular systems.