@article { ISI:000254697200009, title = {Purification and characterization of a T-antigen specific lectin from the coelomic fluid of a marine invertebrate, sea cucumber (Holothuria scabra)}, journal = {Fish \& Shellfish Immunology}, volume = {24}, number = {4}, year = {2008}, month = {APR}, pages = {450-458}, publisher = {ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD}, address = {24-28 OVAL RD, LONDON NW1 7DX, ENGLAND}, abstract = {

A novel lectin was purified from the coelomic fluid of the sea cucumber Holothuria scabra (HSL), subjected to bacterial challenge. HSL is a monomeric glycoprotein of molecular mass 182 kDa. The lectin is highly thermostable as it retains full activity for 1 h at 80 degrees C. Further, the hemagglutination activity of HSL is unaffected by pH in the range 2-11. Unlike other lectins purified from marine invertebrates, the hemagglutination activity of HSL does not require any divalent metal ions. The affinity profile of HSL was studied by a combination of hemagglutination inhibition and fluorescence spectroscopy. HSL binds to desialylated glycoproteins, Me alpha Gal, T-antigen and T (alpha-ser)-antigen with a distinction between beta 1-4 and beta 1-3 linkages. Me alpha-T-antigen was a potent ligand having highest affinity (K-a 8.32 x 10(7) M-1). Monosaccharide binding is enthalphically driven while disaccharide binding involves both entropic and enthalpic contributions. (c) 2008 Elsevier Ltd. All rights reserved.

}, keywords = {Fluorescence spectroscopy, Holothuria scabra, Lectin, marine invertebrate, Thermodynamic properties}, issn = {1050-4648}, doi = {10.1016/j.fsi.2008.01.002}, author = {Gowda, Nagaraj M. and Goswami, Usha and Khan, Mohammad Islam} } @article { ISI:000259829900004, title = {T-antigen binding lectin with antibacterial activity from marine invertebrate, sea cucumber (Holothuria scabra): possible involvement in differential recognition of bacteria}, journal = {Journal of Invertebrate Pathology}, volume = {99}, number = {2}, year = {2008}, month = {OCT}, pages = {141-145}, publisher = {ACADEMIC PRESS INC ELSEVIER SCIENCE}, type = {Article}, address = {525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA}, abstract = {

In invertebrates, cellular and humoral components are evolved to maintain their body immunity and integrity. Both these factors respond to different antigens such as microorganisms, vertebrate erythrocytes and foreign proteins. In this article, we report a study of a lectin (HSL) involved in immune response in the echinoderm, sea Cucumber (Holothuria scabra). Correlative studies indicate that the expression of this defensive lectin is induced by bacterial challenge, wherein cell wall glycoconjugates of bacteria are involved in lectin induction. HSL showed strong broad spectrum antibacterial activity against both gram-positive and gram-negative bacteria. Under in vitro conditions, purified HSL mediate agglutination of the test bacteria, there by indicating a possible mode of action in physiological situation. (c) 2008 Elsevier Inc. All rights reserved.

}, keywords = {agglutination, antibacterial activity, coelomic fluid, Holothuria scabra, Lectin, sea cucumber}, issn = {0022-2011}, doi = {10.1016/j.jip.2008.04.003}, author = {Gowda, Nagaraj M. and Goswami, Usha and Khan, Mohammad Islam} } @article { ISI:000325949600005, title = {Kinetics and thermodynamics of glycans and glycoproteins binding to holothuria scabra lectin: a fluorescence and surface plasmon resonance spectroscopic study}, journal = {Journal of Fluorescence}, volume = {23}, number = {6}, year = {2013}, month = {NOV}, pages = {1147-1155}, publisher = {SPRINGER/PLENUM PUBLISHERS}, address = {233 SPRING ST, NEW YORK, NY 10013 USA}, abstract = {

Holothuria scabra produces a monomeric lectin (HSL) of 182 kDa. HSL showed strong antibacterial activity and induced bacterial agglutination under in vitro conditions, indicating its role in animals{\textquoteright} innate immune responses. Very few lectins have been reported from echinoderms and none of these lectins have been explored in detail for their sugar-binding kinetics. Affinity, kinetics and thermodynamic analysis of glycans and glycoproteins binding to HSL were studied by fluorescence and surface plasmon resonance spectroscopy. Lectin binds with higher affinity to O-linked than N-linked asialo glycans, and the affinities were relatively higher than that for sialated glycans and glycoproteins. T-antigen alpha-methyl glycoside was the most potent ligand having the highest affinity (Ka 8.32 x10(7) M-1). Thermodynamic and kinetic analysis indicated that the binding of galactosyl Tn-antigen and asialo glycans is accompanied by an enthalpic contribution in addition to higher association rate coupled by low activation energy for the association process. Presence of sialic acid or protein matrix inhibits binding. Higher affinity of HSL for O-glycans than N-glycans had biological implications; since HSL specifically recognizes bacteria, which have mucin or O-glycan cognate on their cell surfaces and play a major role in animal innate immunity. Since, HSL had higher affinity to T-antigen, makes it a useful tool for cancer diagnostic purpose.

}, keywords = {Holothuria scabra, Kinetic analysis, Lectin, Surface plasmon resonance spectroscopy, Thermodynamic properties}, issn = {1053-0509}, doi = {10.1007/s10895-013-1244-4}, author = {Gowda, Nagaraj M. and Gaikwad, Sushama M. and Khan, Mohammad Islam} }