
Jacalin is a plant-based
lectin
Lectins are carbohydrate-binding proteins that are highly specific for sugar groups that are part of other molecules, so cause agglutination of particular cells or precipitation of glycoconjugates and polysaccharides. Lectins have a role in rec ...
, but not a
legume lectin, found in
jackfruit
The jackfruit (''Artocarpus heterophyllus''), also known as jack tree, is a species of tree in the fig, mulberry, and breadfruit family ( Moraceae). Its origin is in the region between the Western Ghats of southern India, all of Bangladesh, ...
. It has been studied for capturing O-
glycoprotein
Glycoproteins are proteins which contain oligosaccharide chains covalently attached to amino acid side-chains. The carbohydrate is attached to the protein in a cotranslational or posttranslational modification. This process is known as g ...
s such as
mucins
Mucins () are a family of high molecular weight, heavily glycosylated proteins ( glycoconjugates) produced by epithelial tissues in most animals. Mucins' key characteristic is their ability to form gels; therefore they are a key component in mo ...
and
IgA1, for potential applications in human
immunology
Immunology is a branch of medicineImmunology for Medical Students, Roderick Nairn, Matthew Helbert, Mosby, 2007 and biology that covers the medical study of immune systems in humans, animals, plants and sapient species. In such we can see ther ...
.
Glycobiology:Elucidation of binding specificity of Jacalin toward O-glycosylated peptides: quantitative analysis by frontal affinity chromatography
/ref>
Jacalin belongs to a family of galactose-binding lectins containing the Jacalin-like lectin domain and it has a tetrameric two-chain structure with a weight of 66 kDa
Jacalin is preferably used in applications to isolate IgA from human serum, isolating human plasma glycoproteins and for applications in histochemistry. The lectin is blood group non-specific after neuraminidase treatment and agglutinates human erythrocytes at a concentration of ≥ 7,8 µg/ml.
A post-translational proteolytic modification of Jacalin gives the lectin a novel carbohydrate-binding site involving the N-terminus
The N-terminus (also known as the amino-terminus, NH2-terminus, N-terminal end or amine-terminus) is the start of a protein or polypeptide, referring to the free amine group (-NH2) located at the end of a polypeptide. Within a peptide, the ami ...
of the a-chain. The relative affinities of the lectin for galactose derivatives, as well as the structural basis of its T-antigen specificity, are explained by its protein structure
See also
* Common Bean
''Phaseolus vulgaris'', the common bean, is a herbaceous annual plant grown worldwide for its edible dry seeds or green, unripe pods. Its leaf is also occasionally used as a vegetable and the straw as fodder. Its botanical classification, alo ...
References
{{reflist
Plant lectins