Pro identifiers are URIs, globally unique identifiers.
Two forms of PURLs
The URIs have one of two forms:
where d is a digit.
In the second case, the identifiers denote the class of proteins that the UniProt accession is about. PRO uses these identifiers for the gene-organism level terms, and is considering using them for the isoform terms.
http://purl.obolibrary.org/obo/PR_Q10322 is the class of proteins sometimes known as *Probable E3 ubiquitin-protein ligase dma1* in Schizosaccharomyces. To be clear, this class of proteins includes any that is a gene product of the gene *dma1*, or of a population variant at the same locus, e.g. some mutation of *dma1*.
http://purl.obolibrary.org/obo/pr.owl is the latest released version of the Protein Ontology in OWL 2 RDF/XML syntax. This is the reasoned-over version, one which has all the additional axioms that are inferred from the original edited ontology.
http://purl.obolibrary.org/obo/pr.obo is the latest released version of the Protein Ontology in OBO format.
http://purl.obolibrary.org/obo/pr/yyyy-mm-dd/pr.owl is the version of the Protein Ontology in OWL 2 RDF/XML syntax that was released on day number dd of month number mm of the year yyyy. If you access that ontology you will find the ontologyIRI is
http://purl.obolibrary.org/obo/pr.owl and the versionIRI is
http://purl.obolibrary.org/obo/pr/yyyy-mm-dd/pr.owl These versions can be counted on to be stable even when new versions are released and projects that manage change carefully will want to import a specific version of PR.
http://purl.obolibrary.org/obo/pr/yyyy-mm-dd/pr.obo is the version of the Protein Ontology in OBO format that was released on day number dd of month number mm of the year yyyy.
http://purl.obolibrary.org/obo/pr/pr-asserted.owl is the asserted, or edited version of the latest release of PRO.
http://purl.obolibrary.org/obo/pr/yyyy-mm-dd/pr-asserted.owl is the asserted version of PRO, in OWL 2 RDF/XML syntax, released on yyyy-mm-dd
http://purl.obolibrary.org/obo/pr/yyyy-mm-dd/pr-asserted.obo is the asserted version of PRO, in OBO format, released on yyyy-mm-dd
http://purl.obolibrary.org/obo/pr/pr-dev.owl is the current development version (asserted) of PRO in OWL. This file may change day to day, and might even be broken. If you use it, understand the caveats.
http://purl.obolibrary.org/obo/pr/pr-dev.obo is the current development version (asserted) of PRO in OBO. This file may change day to day, and might even be broken. If you use it, understand the caveats.
Other project related PURLs
http://purl.obolibrary.org/obo/pr points to the PRO Project Home Page
http://purl.obolibrary.org/obo/pr/repository points to the browseable repository (currently at google code)
http://purl.obolibrary.org/obo/pr/wiki points to the pro wiki (on which this page is kept)
http://purl.obolibrary.org/obo/pr/browse points the PRO ontology browseable using OntoBee
http://purl.obolibrary.org/obo/pr/tracker points the PRO ontology issue tracker
PURLs for the project other than /obo/pr.owl, are in the /obo/pr PURL domain, whose current maintainer is the protein-ontology PURL group. The members of the protein_ontology PURL group include the OBO PURL group, as well as dnatale(Darren Natale) and alanruttenberg(Alan Ruttenberg). Any of these members has permission to create or change a PURL that starts with /obo/pr/.
PURLS are managed at http://purl.org/
The OBO Foundry ID Policy is documented at http://obofoundry.org/id-policy.shtml