Natural Products Ontology	Core Ontology for Biology and Biomedicine	Source
http://purl.obolibrary.org/obo/PR_000000001	http://www.owl-ontologies.com/NPOntology.owl#Protein	LOOM
http://purl.obolibrary.org/obo/CL_0000000	http://purl.org/biotop/biotop.owl#Cell	LOOM
http://purl.obolibrary.org/obo/BFO_0000023	http://purl.org/biotop/biotop.owl#Role	LOOM