MP2/6-311++G(d,p) study on galactose–aromatic residue analog complexes in different position-orientations of the saccharide relative to aromatic residue

Three‐Dimensional Potential Energy Surface of Selected Carbohydrates’ CH/π Dispersion Interactions Calculated by High‐Level Quantum Mechanical Methods

“…This means that more hydrogen atoms interacting with the aromatic system makes the interaction stronger. [12] Our data show that the hydrogen atoms are not equivalent for the interaction. In order to predict how much each hydrogen atom is involved in CH/p interactions with larger aromatic moieties, we computed a Boltzmann distribution (see Table 2).…”

“…[11] In order to study the energetics of these interactions, it is necessary to use post-Hartree-Fock methods such as Møller-Plesset (MPn) or the coupled cluster (CC) method. [11,12] Uncorrelated Hartree-Fock (HF) methods, or basic density functional theory (DFT) methods, fail to model these interactions as attractive. Several empirical corrections to the DFT functional have been developed by Grimme [13,14] , Jurečka, [15] and Elstner and Hobza, [16] which provide a better description of the dispersion interaction in DFT methods.…”

“…Interaction energies of carbohydrate-aromatic complexes have been recently calculated for geometries derived from experimental structures of carbohydrate-protein complexes [12] or from ad hoc generated complexes. [26,27] Here we present the first systematic scan of the potential energy surface of carbohydrate-aromatic assemblies, namely for b-dglucopyranose, a-l-fucopyranose and b-d-mannopyranose complexed with benzene ( Figure 2).…”

Structural and Functional Insight into the Carbohydrate Receptor Binding of F4 Fimbriae-producing Enterotoxigenic Escherichia coli

“…The sugar ring of galactose is sandwiched between the side chains of Phe 150 and Lys 167 . The presence of an aromatic residue facing the non-polar surface of the galactopyranose is a recurrent feature of galactose-binding proteins (45).…”

An evaluation of the GLYCAM06 and MM3 force fields, and the PM3-D* molecular orbital method for modelling prototype carbohydrate–aromatic interactions

“…Amino acids having aromatic side chains (tryptophan, tyrosine and phenylalanine) are frequently found in protein active sites which recognize carbohydrates, and the importance of the associated arene-carbohydrate interactions is well recognized [6][7][8][9]. A number of experimental [10,11] and theoretical [12][13][14][15] studies have shown that there are major contributions to these intermolecular interactions involving the aliphatic C-H and O-H groups which point towards the aromatic system. The corresponding protein crystal structures display mainly C-H-interactions, but in the binary complexes, fucose-toluene and ␣-methyl glucose-toluene, the most stable structures involve O-H-interactions, which are reflected in their infrared spectra [11].…”