PolysacDB: A comprehensive database of microbial polysaccharide antigens and their antibodies

Home | Search | Advance Search | Browse | Online Submission | Documentation & FAQ | Team | Contact us

Citation: Aithal A, Sharma A, Joshi S, Raghava GPS, Varshney GC (2012) PolysacDB: A Database of Microbial Polysaccharide Antigens and Their Antibodies. PLoS ONE 7(4): e34613. doi:10.1371/journal.pone.0034613
Total Entries - 1

Entry No. - 1   [TOP]
PolysacDB ID1006
Carbohydrate NameGlucurunoxylomannan   (Drugpedia)
Carbohydrate ClassCapsular polysaccharide
MicrobeCryptococcus neoformans   (NCBI Taxonomy)   (Drugpedia)
Basic StructureA linear (1-->3)-linked mannan backbone singly substituted with nonreducing β(1-->2) xylose and β(1-->2) glucuronic acid side branches ; O-acetyl groups are present at C-6 of the mannosyl residues
BCSDB Structure130362
Proposed functionsAntiphagocytic ; an important virulence factor
Antigenic Nature used to produce antibodiesGlycoconjugates
Carrier NameTetanus toxoid
Conjugation MethodGXM was derivatized by the following two methods. (i) In method 1, ADH [adipic acid dihydrazide] was introduced into GXM by the activation of carboxyl groups with EDAC. GXM (5 mg/ml of 0.2 M NaCl) was derivatized with 0.5 M ADH and 0.1 M EDAC at pH 4.85 for 3.5 h at room temperature, using a pH Stat. After extensive dialysis against 0.2 M NaCl, the reaction mixture was passed through a 2B-CL Sepharose column (1.5 by 30 cm) equilibrated in 0.2 M NaCl. The fractions containing GXM were pooled and concentrated to the original volume. (ii) In method 2, ADH was introduced into GXM by the activation of hydroxyl groups with CNBr. GXM (5 mg/ml of 0.2 M NaCl) was activated with an equal weight of CNBr at pH 10.5 for 6 min at 4°C, using a pH Stat. An equal volume of 0.5 M NaHCO3 (pH 8.5) containing 0.5 M ADH was added. The reaction mixture was tumbled at 3 to 8°C for 18 to 20 h, dialyzed against 0.2 M NaCl, and passed through a 2B-CL Sepharose column (1.5 by 30 cm). The fractions containing GXM were pooled and concentrated to the original volume. The reaction mixture, containing equal concentrations (3.0 to 7.5 mg/ml) of GXM-AH (derivatized by either method) and TT or rEPA in 0.2 M NaCl, was brought to pH 5.6 with 0.05 N HCl, and 0.05 to 0.1 M EDAC was added; the pH was maintained at 5.6 in a pH Stat for 1 to 3 h at 4°C. The reaction mixture was dialyzed against 0.2 M NaCl at 3 to 8°C and passed through a Sepharose 2B-CL column (1.5 by 30 cm) equilibrated in 0.2 M NaCl. The void volume fractions containing the GXM and the protein were pooled and stored in 0.01% thimerosal at 3 to 8°C
AntibodiesMab 3B6
Antibody type and classIgM
Assay SystemELISA
Cross-reactivityThis antibody cross-reacted with Serotypes A, B, C and D
Proposed epitopesN\A
IEDB EpitopeN/A
Proposed UtilityHuman glucurunoxylomannan monoclonal antibodies are essential to address questions regarding the role of glucurunoxylomannan antibodies in protection against cryptococcal infections
Curator IDAA + AS
Date of Curation02-01-2010
ReferencesPMC173409


Bioinformatics Centre, Institute of Microbial Technology, Sec - 39A, Chandigarh, India - 160036