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Structure and Stability of Carbohydrate–Lipid Interactions. Methylmannose Polysaccharide–Fatty Acid Complexes
Author(s) -
Liu Lan,
Siuda Iwona,
Richards Michele R.,
Renaud Justin,
Kitova Ele.,
Mayer Paul M.,
Tieleman D. Peter,
Lowary Todd L.,
Klassen John S.
Publication year - 2016
Publication title -
chembiochem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.05
H-Index - 126
eISSN - 1439-7633
pISSN - 1439-4227
DOI - 10.1002/cbic.201600123
Subject(s) - chemistry , carbohydrate , dissociation (chemistry) , methylene , polysaccharide , stereochemistry , molecular dynamics , fatty acid , crystallography , organic chemistry , computational chemistry
We report a detailed study of the structure and stability of carbohydrate–lipid interactions. Complexes of a methylmannose polysaccharide (MMP) derivative and fatty acids (FAs) served as model systems. The dependence of solution affinities and gas‐phase dissociation activation energies ( E a ) on FA length indicates a dominant role of carbohydrate–lipid interactions in stabilizing (MMP+FA) complexes. Solution 1 H NMR results reveal weak interactions between MMP methyl groups and FA acyl chain; MD simulations suggest the complexes are disordered. The contribution of FA methylene groups to the E a is similar to that of heats of transfer of n ‐alkanes from the gas phase to polar solvents, thus suggesting that MMP binds lipids through dipole‐induced dipole interactions. The MD results point to hydrophobic interactions and H‐bonds with the FA carboxyl group. Comparison of collision cross sections of deprotonated (MMP+FA) ions with MD structures suggests that the gaseous complexes are disordered.