Effect of Non-Enzymatic Glycation on the Hydration of Collagen and Membrane Phospholipids: A DFT Study of the Energetics and Structure of the First Hydration Shell

Abstract

The effect of non-enzymatic glycation and the formation of advanced glycation end-products (AGEs) on the structure and energetic characteristics of the first hydration shell
of model collagen fragments (lysine → fructosyllysine → glucosepane) and a membrane phospholipid (phosphatidylethanolamine → deoxy-D-fructosylphosphatidylethanolamine)
has been studied using density functional theory (DFT) methods. It is shown that at the early stage of glycation
(Amadori products: fructosyllysine and deoxy-D-fructosylphosphatidylethanolamine), neutralization of the positively charged ε-NH₃⁺ group of lysine or the
head-group NH₃⁺ group of phosphatidylethanolamine leads to the loss of strong ion-dipole interactions with water. The average binding energy per water molecule
decreases (for collagen from –80.8 to –42.3 kJ/mol; for phosphatidylethanolamine from –74.1 to –56.1 kJ/mol); however, due to the appearance of new sugar hydroxyl groups,
the number of tightly bound water molecules in the first hydration shell increases (for collagen model fragments from 3 to 5; for the phospholipid from 7 to 10).
At the late stage (formation of glucosepane), both original charged groups (lysine and arginine) are converted into neutral heterocyclic moieties, causing a
sharp decrease in hydrophilicity: the association energy drops to –37.7 kJ/mol, and the number of water molecules in the shell is reduced by half.

Speaker

Kirill V. Berezin
N.G. Chernyshevsky Saratov State National Research University, Saratov V.N. Tatishchev Astrakhan State University, Astrakhan
Russia

Upload Report

Discussion

Ask question