학술논문

The carbohydrate-binding specificity and molecular modelling of Canavalia maritima and Dioclea grandiflora lectins
Document Type
article
Source
Memórias do Instituto Oswaldo Cruz. December 1996 91(6)
Subject
Canavalia maritima
carbohydrate-binding specificity
Diocleinae
Dioclea grandiflora
lectins
molecular modelling
Language
English
ISSN
0074-0276
Abstract
The carbohydrate-binding specificity of lectins from the seeds of Canavalia maritima and Dioclea grandiflora was studied by hapten-inhibition of haemagglutination using various sugars and sugar derivatives as inhibitors, including N-acetylneuraminic acid and N-acetylmuramic acid. Despite some discrepancies, both lectins exhibited a very similar carbohydrate-binding specificity as previously reported for other lectins from Diocleinae (tribe Phaseoleae, sub-tribe Diocleinae). Accordingly, both lectins exhibited almost identical hydropathic profiles and their three-dimensional models built up from the atomic coordinates of ConA looked very similar. However, docking experiments of glucose and mannose in their monosaccharide-binding sites, by comparison with the ConA-mannose complex used as a model, revealed conformational changes in side chains of the amino acid residues involved in the binding of monosaccharides. These results fully agree with crystallographic data showing that binding of specific ligands to ConA requires conformational chances of its monosaccharide-binding site.