chem-bla-ics: July 2016

Use of the BridgeDb metabolite ID mapping database in PathVisio

A long time ago Martijn van Iersel wrote a PathVisio plugin that visualizes 2D chemical structures of metabolites in pathways as found on WikiPathways. Some time ago I tried to update it to a more recent CDK version, but did not have enough time at the time to get it going. However, John May's helpful DepictionGenerator made it a lot easier, so I set out this morning in updating the code base to use this class and CDK 1.5.13 (well, strictly speaking it's running a prerelease (snapshot) of CDK 1.5.14). With success:

The released version is a bit more tweaked and shows the 2D structure diagram more filling the Structure tab. I have submitted the plugin to the PathVisio Plugin Repository.

Now, you may know that these GPML pathways only contain identifiers, and no chemical structures.

Jul

Setting up a local SPARQL endpoint

... has never been easier, and I have to say, with Virtuoso it already was easy.

Step 1: download the jar and fire up the server

OK, you do need Java installed, and for many this is still the case, despite Oracle doing their very best to totally ruin it for everyone. But seriously, visit the Blazegraph website (@blazegraph) and download the jar and type:

$ java -jar blazegraph.jar

It will give some output on the console, including a webpage with SPARQL endpoint, upload form etc.

Jul

Metabolomics 2016 Write up #1: some interesting bits

A good conference needs some time to digest. A previous supervisor advised me that a conference travel of 5 days takes 5 full day to follow up on everything. I think he is right, though few of us actually block our schedules to make time for that.

Jul

Harmonized identifiers in the WikiPathways RDF

WikiPathways described biological processes. Entities in these processes are genes, gene products, like miRNAs, proteins, and metabolites. The pathways do not describe what these entities are, but only provide identifiers in external databases allowing you to study the identity in those databases. Therefore, for metabolites you will not find chemical graphs but identifiers from HDMB, CAS, KEGG, ChEBI, and others.

Jul

Two Apache Jena SPARQL query performance observations

Doing searches in RDF stores is commonly done with SPARQL queries. I have been using this with the semantic web translation of WikiPathways by Andra to find common content issues, though sometimes combined with some additional Java code. For example, find PubMed identifiers that are not numbers.