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 == Publication Abstract from PubMed ==
-Jacalin, a tetrameric two-chain lectin (66,000 Mr) from jackfruit seeds, is highly specific for the tumour associated T-antigenic disaccharide. The crystal structure of jacalin with methyl-alpha-D-galactose reveals that each subunit has a three-fold symmetric beta-prism fold made up of three four-stranded beta-sheets. The lectin exhibits a novel carbohydrate-binding site involving the N terminus of the alpha-chain which is generated through a post-translational modification involving proteolysis, the first known instance where such a modification has been used to confer carbohydrate specificity. This new lectin fold may be characteristic of the Moraceae plant family. The structure provides an explanation for the relative affinities of the lectin for galactose derivatives and provides insights into the structural basis of its T-antigen specificity.
+Jacalin is among the most thoroughly studied lectins. Its carbohydrate-binding site has also been well characterized. It has been postulated that the lower affinity of beta-galactosides for jacalin compared with alpha-galactosides is caused by steric interactions of the substituents in the former with the protein. This issue has been explored energetically and structurally using different appropriate carbohydrate complexes of jacalin. It turns out that the earlier postulation is not correct. The interactions of the substituent with the binding site remain essentially the same irrespective of the anomeric nature of the substitution. This is achieved through a distortion of the sugar ring in beta-galactosides. The difference in energy, and therefore in affinity, is caused by a distortion of the sugar ring in beta-galactosides. The elucidation of this unprecedented distortion of the ligand as a strategy for modulating affinity is of general interest. The crystal structures also provide a rationale for the relative affinities of the different carbohydrate ligands for jacalin.
-A novel mode of carbohydrate recognition in jacalin, a Moraceae plant lectin with a beta-prism fold.,Sankaranarayanan R, Sekar K, Banerjee R, Sharma V, Surolia A, Vijayan M Nat Struct Biol. 1996 Jul;3(7):596-603. PMID:8673603<ref>PMID:8673603</ref>
+Jacalin-carbohydrate interactions: distortion of the ligand molecule as a determinant of affinity.,Abhinav KV, Sharma K, Swaminathan CP, Surolia A, Vijayan M Acta Crystallogr D Biol Crystallogr. 2015 Feb;71(Pt 2):324-31. doi:, 10.1107/S139900471402553X. Epub 2015 Jan 23. PMID:25664742<ref>PMID:25664742</ref>
 From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>