Binding gangliosides

Berenson CS, Sayles KB, Huang J, Reinhold VN, Garlipp MA, Yohe HC. Nontypeable Haemophilus influenzae-binding gangliosides of human respiratory (HEp-2) cells have a requisite lacto/neolacto core structure. FEMS Immunol Med Microbiol. 2005 45(2) 171-182. 

W. E. Minde, C. Roach, W. G. J. Hoi, and C. L. Verlinde, Structure-based exploration of the ganglioside GM1 binding sites of Escherichia coli heat-labile... 

Fig. 8.7 CTB-GM1-ganglioside binding ELISA assay. Plates, coated first with GMrganglioside and bovine serum albumin (BSA), respectively, were irrigated with total soluble plant protein from chloroplast transgenic lines (3 and 7) and 300 ng of purified bacterial CTB. The absorbance of the GM1-ganglioside-CTB-antibody complex in each case was measured at 405 nm. Total soluble protein from untransformed plants was used as the negative control.

Two of the most widely spread and well-studied enterotoxigenic forms of bacterial diarrhea are ETEC and Vibrio cholerae. The toxins they produce, labile toxin (LT) and cholera toxin (CT) respectively, are very similar in primary sequence, structure, and mechanism of action [72]. They are homologous multi-subunit proteins in which the non-toxic B subunit mediates GMj ganglioside binding, and thus are candidates for vaccines that can neutralize toxin activity. 

Hanisch, F.-G., Hacker, J., and Schroten, H. (1993). Specificity of S fimbriae on recombinant Escherichia coli Preference binding to gangliosides expressing NeuGc-a-(2-3)Gal and NeuAc-a-NeuAc. Infect. Immun. 61, 2108-2115. 

Caveolae can mediate the delivery of CtxB that binds to GM1 ganglioside at the plasma membrane and is delivered to intracellular compartments. Cholera toxin, produced by Vibrio cholerae, consists of five identical subunits B and one A chain. In addition to labeled SV40 and caveolin-1-GFP, CtxB is one of the most commonly used caveolae markers. However, two groups reported that the toxin is internalized by either a clathrin-independent caveolae pathway or a clathrin-dependent uptake, bringing its selectivity/specificity into question (31,81,118). We controlled the suitability of this marker for COS-7 cells pretreated with CPZ, mpCD, and filipin and as expected, the uptake was not influenced by CPZ treatment but was strongly decreased by the latter two (data not shown). 

In both of these cases, the ligand (sialic acid) for the analyte of interest (influenza vims) was covalently linked to the PDA backbone generated upon photopolymerization. Functional sensors based on ligands that are noncovalently incorporated into liposomes have also been reported (Charych et al. 1996 Pan and Charych 1997). Mixed liposomes as well as mixed thin films on glass containing a combination of the ganglioside GMl and diacetylene lipids detect the presence of cholera toxin, a protein that binds to GMl. 

Mucosal adjuvants Bind to M cells and GMl ganglioside receptors on mucosal epithelium CT toxin... 

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