The Chemical Entities of Biological Interest (ChEBI) ontology is downloaded weekly from EMBL-EBI at http://www.ebi.ac.uk/chebi/. The data is made available under the Creative Commons License (CC BY 3.0, http://creativecommons.org/licenses/by/3.0/). For more information see: Degtyarenko et al. (2008) ChEBI: a database and ontology for chemical entities of biological interest. Nucleic Acids Res. 36, D344–D350.
Bacterial polysaccharide derivatives of glycerol phosphate or ribitol phosphate linked via phosphodiester bonds, whose main function is to fortify the cell wall. In some parasites, they serve as a site of attachment to mucosal membranes.