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.
A polysaccharide derivative comprising a trisaccharide repeating unit consisting of 2-acetamido-4-amino-2,4-dideoxy-alpha-D-fucose and two alpha-D-galacturonic acid residues linked sequentially (1->4) and (1->3) and with the trisaccharide repeats themselves being linked (1->3); corresponds to the serotype 1 capsular polysaccharide (CPS) of Streptococcus pneumoniae.