Legume lectin


Legume lectin

The legume lectins are a family of sugar binding proteins or lectins found in theseeds and, in smaller amounts, in the roots, stems, leaves and bark ofplants belonging to the Fabaceae family [Sharon, N. & Lis, H. (1990) FASEB J., 4, 3198-3208] [Loris, R., Hamelryck, T., Bouckaert, J. & Wyns, L. (1998) Biochim.Biophys. Acta, 1383, 9-36] . The exact function of the legume lectins "in vivo" is unknown but they are probably involved in the defense of plantsagainst predators. Related proteins in other plant families and in animals have also been found. They have been used fordecades as a model system for the study of protein-carbohydrateinteractions, because they show an amazing variety of bindingspecificities and are easy to obtain and purify. Over the years, aquite impressive amount of structural data has been gathered [Loris, R., Hamelryck, T., Bouckaert, J. & Wyns, L. (1998) Biochim. Biophys. Acta, 1383, 9-36] . Well-studied members of this protein family include phytohemagglutinin and concanavalin A.

ugar binding by legume lectins

The legume lectins use an ingenious framework for bindingspecific sugars. This framework consists of aconserved monosaccharide binding site in which four conserved residuesfrom four separate regions in the protein confer affinity (see figure), a variable loop that confers monosaccharidespecificity and a number of subsites around the monosaccharide bindingsite that harbor additional sugar residues or hydrophobic groups [Loris, R., Hamelryck, T., Bouckaert, J. & Wyns, L. (1998) Biochim. Biophys. Acta, 1383, 9-36] .

References


Wikimedia Foundation. 2010.

Look at other dictionaries:

  • Lectin — Lectins are sugar binding proteins which are highly specific for their sugar moieties. They typically play a role in biological recognition phenomena involving cells and proteins. For example, some bacteria use lectins to attach themselves to the …   Wikipedia

  • Mannan-binding lectin — Mannose binding lectin (protein C) 2, soluble PDB rendering based on 1hup …   Wikipedia

  • Concanavalin A — Crystallographic structure of a tetramer of jack bean concanavalin A (the monomers are colored cyan, green, red, and magenta respectively). Calcium (gold) and manganese cations (grey) are depicted as spheres …   Wikipedia

  • Collectin — Collectins are soluble pattern recognition receptors (PRRs) belonging to the superfamily of collagen containing C type lectins. Eight collectins have been identified including mannan binding lectin (MBL), surfactant protein A (SP A), surfactant… …   Wikipedia

  • Mannose receptor — mannose receptor, C type 1 Identifiers Symbol MRC1 Alt. symbols CD206 Entrez 4360 …   Wikipedia

  • Lectina — Hemaglutinina, una lectina vista en posición lateral. Las lectinas son proteínas que se unen a azúcares con una elevada especificidad para cada tipo distinto. Su principal papel está en los fenómenos de reconocimiento, tanto a nivel molecular… …   Wikipedia Español

  • Calreticulin — PDB rendering based on 1hhn …   Wikipedia

  • Mitogen — See also: Growth Factor A mitogen is a chemical substance that encourages a cell to commence cell division, triggering mitosis. A mitogen is usually some form of a protein. Mitogenesis is the induction (triggering) of mitosis, typically via a… …   Wikipedia

  • Myelin-associated glycoprotein — Identifiers Symbol MAG Alt. symbols GMA Entrez 4099 …   Wikipedia

  • N-Acetylglucosamine receptor — heterogeneous nuclear ribonucleoprotein M Identifiers Symbol HNRPM Alt. symbols NAGR1 Entrez 4670 …   Wikipedia


Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.