Showing papers by "Jesús Jiménez-Barbero published in 1994"
TL;DR: The binding of different synthetic monodeoxy, O-methyl and fluorodeoxy derivatives of methyl beta-lactoside to galectin-1 from bovine heart has been studied to probe the role of hydrogen bonding in the recognition and binding, suggesting favourable interactions of the methyl groups which may come into contact with hydrophobic residues at the periphery of the combining site.
Abstract: The binding of different synthetic monodeoxy, O-methyl and fluorodeoxy derivatives of methyl beta-lactoside to galectin-1 from bovine heart has been studied to probe the role of hydrogen bonding in the recognition and binding. The energetic contributions of the hydroxyl groups of methyl beta-lactoside directly involved in the interaction have been estimated and the nature of the protein residues involved has been predicted on the basis of the free energy data. Interpretations of the results have been sustained by molecular modeling of the three-dimensional structure of the sugars in solution. One side of the disaccharide molecule is not involved (HO-6 and HO-2') or only marginally involved (HO-3') in hydrogen bonding. Moreover, O-methylation at these positions causes an enhancement of the binding, suggesting favourable interactions of the methyl groups which may come into contact with hydrophobic residues at the periphery of the combining site. Hydrogen-bonding interactions are almost exclusively restricted to the other side of the molecule: the C-4' and C-6' hydroxyl groups act as donors of the strongest hydrogen bonds to charged groups of the lectin, while the C-3 hydroxyl group participates in a strong hydrogen bond with a neutral group. The results also suggest that the N-acetyl NH group in N-acetyllactosamine, as well as the hydroxyl group at position C-2 in methyl beta-lactoside, are involved in a polar interaction with neutral groups of the combining site. This hydrogen-bonding pattern contrasts markedly with that previously reported for the two galactose-specific Ricinus communis lectins. The recognition of different epitopes of the same basic structure underlies the differences in the oligosaccharide-binding specificities of galectin-1 and the R. communis lectins.
35 citations
TL;DR: The water-soluble cell-wall polysaccharides isolated from strains CBS 352.72 and 310.38 of Talaromyces flavus have been investigated by chemical analyses and NMR studies and two different skeletons coexist, having the structures: [formula:see text].
34 citations
TL;DR: The structure of two cell-wall polysaccharides isolated from three different strains of Penicillium expansum, the type species of the genus, have been established by 1D and 2D NMR spectroscopy, and also by methylation analyses.
30 citations
TL;DR: The synthesis of all the possible monomethyl ethers of methyl beta-lactoside has been performed from 1 in a straightforward way, making use of the different reactivity of the hydroxyl groups in alkylation and stannylation reactions.
21 citations
TL;DR: In this paper, the solution conformation of tri-and tetrasaccharide obtained by enzymatic degradation of glucan has been analyzed using molecular mechanics and dynamics calculations and nuclear magnetic resonance data.
11 citations
TL;DR: In this paper, the conformation of methyl 4-O-(β-D-galactopyranosyl)-β- D-xylopyranoide (1) and benzyl 3-O(β-d-galacticopyranosi) was investigated.
10 citations
TL;DR: The binding of the different compounds to ricin, the galactose-specific toxin from Ricinus communis, has been investigated and the results confirm the involvement of the C-3 region in a nonpolar interaction with the protein at the periphery of the combining site.
10 citations
9 citations
TL;DR: In this paper, the solution conformation of several halodeoxy analogues of methyl β-lactoside 1 has been analyzed using molecular mechanics and dynamics calculations and nuclear magnetic resonance data (variable temperature and NOE experiments).
4 citations