P S Appukuttan
Articles written in Journal of Biosciences
Volume 4 Issue 3 September 1982 pp 257-261
An α-D-galactose-specific lectin from the seeds of jack fruit (
Volume 5 Issue S1 December 1983 pp 131-135
N-Acetyl-D-galactosamine in β-linkage being ubiquitous in cell surface glycoproteins, their interaction with lectins specific for this sugar moiety may be a significant event in cell adhesion phenomena. This article discusses the common β-N-acetyl galactosamine-specific lectins, with particular stress on the lectin from winged beans (
Volume 7 Issue 1 March 1985 pp 7-14
The effect of chemical modification of amino acid residues essential for sugar binding in the α-D-galactoside specific jack fruit (
Volume 11 Issue 1-4 March 1987 pp 41-46
Lectins, the divalent or polyvalent (glyco) proteins of non-immune origin of the cells agglutinate cells or other materials, that display more than one saccharide of sufficient complementarity. Lectins considered ‘identical’ in terms of mono-and disaccharide specificity can be differentiated by their ability to recognise the fine differences in more complex structures. The present review discusses the interaction of lectins with various oligosaccharides and their resultant separations due to structural variations.
Volume 11 Issue 1-4 March 1987 pp 331-338
The galactose-binding lectin of human Placenta has been Purified to homogeneity by affinity chromatograPhy on asialo-fetuin column. The Protein, extractable from the tissue only with lactose is aPParently membrane-bound. Molecular weight determination of native Protein and subunit indicated a dimer of l3.4 kDa subunits. Inhibition of haemagglutination with various saccharides indicate that thiodigalactoside is the best inhibitor followed by lactose. However,
Volume 12 Issue 1 March 1987 pp 61-69
An acid α-galactosidase from the seeds of the jack fruit seed (
Volume 20 Issue 3 June 1995 pp 377-384
A β-anomer preference among galactosides has been attributed to the S-type 14 kDa galactose binding lectin. Here the anomeric preference of this lectin from bovine brain (BBL) is reexamined using inhibition of lectin-mediated haemagglutination, binding of the lectin to dot-blotted glycoproteins and affinity electrophoresis of the lectin through polysaccharide-containing gels. 1.0-methyl α-D-galactoside was 8 times better inhibitor of BBL than the corresponding ß-anomer. The terminal galactose in bovine thyroglobulin (exclusively. α-linked) were also nearly 8 times more inhibitory than those in asialofetuin (exclusively ß-linked). The terminal α-galactose-containing endogenous glycoproteins of bovine brain were nearly 4 times better inhibitors of BBL than laminin. Removal of terminal α-galactose units by α-galactosidase fully abolished the BBL binding of thyroglobulin and endogenous glycoproteins. BBL was also sugar-specifically retarded by polyacrylamide gel containing guar galactommannan which bears only α-linked galactose. Data indicated that α-galactosides were sometimes better than their β-anomers in binding to BBL. The significance of this observation to the physiological role of galactose-binding lectins is discussed.
Volume 23 Issue 2 June 1998 pp 137-141
During affinity chromatographic purification of bovine heart 14 kDa galactose-binding lectin (galectin 1) on lactose-Sepharose, several high molecular weight non-lectin glycoproteins were co-purified with the lectin. Glycoprotein binding to the affinity matrix was neither hydrophobic nor ionic, but galactose-dependent since lactose abolished binding. Purification of galectin from the co-purified glycoproteins by affinity electrophoresis in presence of the specific sugar lactose increased agglutination activity about 65-fold, indicating that a complex containing galectin molecules bound sugar specifically to endogenous glycoproteins with sugar binding sites still available had been retained on lactose-Sepharose.