Premium
A DFT study of infrared spectrum of sphingomyelin lipid molecule with calcium cation
Author(s) -
Sugimori K.,
Kawabe H.,
Nagao H.,
Nishikawa K.
Publication year - 2008
Publication title -
international journal of quantum chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.484
H-Index - 105
eISSN - 1097-461X
pISSN - 0020-7608
DOI - 10.1002/qua.21858
Subject(s) - chemistry , conformational isomerism , density functional theory , amide , sphingomyelin , molecule , hydrogen bond , computational chemistry , stereochemistry , crystallography , membrane , biochemistry , organic chemistry
One of the phospholipids, sphingomyelin (SM) is the most abundant component of mammalian membranes in brain and nervous tissues. It plays an important role for apoptosis, aging, and signal transduction with cations. Recently, Yappert and co‐workers have shown that human lens sphingomyelin and its hydrogenated derivative, dihydrosphingomyelin (DHSM) are interacted with Ca 2+ ions to develop human cataracts. In this study, we investigate conformational differences between an isolated SM/DHSM molecule and Ca 2+ ‐coordinated form by using density functional theory (DFT) calculations. B3LYP functional and 6‐31G( d , p ) double‐ζ split‐valence basis set is used for geometry optimization and normal mode analysis. One of resultant conformers of SMs has hydrogen bonding between hydroxyl and phosphate group, whereas another conformer has hydrogen bonding between hydroxyl and amide group. The red shift of calculated vibrational frequencies of amide band due to Ca 2+ is compared with experimental infrared spectrum. Finally, we discuss the Ca 2+ ‐induced effects from conformational and spectroscopic point of view to compare the experimental results. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2008