Conserved waters in legume lectin crystal structures. The importance of bound water for the sequence-structure relationship within the legume lectin family.

TitleConserved waters in legume lectin crystal structures. The importance of bound water for the sequence-structure relationship within the legume lectin family.
Publication TypeJournal Article
Year of Publication1994
AuthorsLoris, R., P. P. Stas, and L. Wyns
JournalJ Biol Chem
Volume269
Issue43
Pagination26722-33
Date Published1994 Oct 28
ISSN0021-9258
KeywordsAmino Acid Sequence, Binding Sites, Calcium, Crystallography, X-Ray, Databases, Factual, Fabaceae, Hydrogen Bonding, Lectins, Ligands, Models, Molecular, Molecular Sequence Data, Plant Lectins, Plants, Medicinal, Protein Conformation, Water
Abstract

An analysis of the water structure in the crystals of different legume lectins has been carried out. Protein hydration is found to be mainly dependent on the detailed local surface characteristics of the protein and will adapt upon the limited conformational changes that are the resultant of crystal packing forces and point mutations. Yet a significant portion of the water positions determined by x-ray crystallography appears to be conserved in all independent crystal structures of a given protein. Some of these waters are specific to this one specific protein, while others are conserved in crystal structures of homologous proteins as well. For those conserved waters, a clear structural role is often evident. Seven water sites were found to be completely conserved in all legume lectin crystal structures, independent of their degree of sequence homology or carbohydrate specificity. Of these, four waters are ligands to the manganese and calcium ions, and one water is located in the saccharide binding site interacting with a conserved Asp and Asn residue. Of the remaining two conserved waters, one of them stabilizes a beta-hairpin, while the other interacts with a beta-bulge structure of the back sheet.

Alternate JournalJ. Biol. Chem.
PubMed ID7929406