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 mixture of cyclic polypeptide streptogramin antibiotics produced by Streptomyces virginiae, S. loidensis, S. mitakaensis, S. pristina-spiralis, S. ostreogriseus, and others. The two major components are virginiamycin M1 (also known as pristinamycin IIA) and virginiamycin S1. Virginiamycin has been widely used as a growth promotion agent in livestock and has been to have bacteriostatic activity against Gram-positive organisms such as staphylococci and streptococci.