Metagenomics analysis special issue in Briefings in Bioinformatics

This month’s Briefings in Bioinformatics issue is devoted to “Bioinformatics approaches and tools for metagenomics analysis“. Yay! I love special issues, especially when they bring together lots of tools to tackle a set of similar problems.

My only gripe is that only 5/11 (45%) articles in the issue are open access 😦

Luckily the best article is among the open access ones – a fantastic review of metagenomic studies, from experimental design and sampling right through to data analysis and submission to public archives, written by Hanno Teeling and Frank Glöckner from the Max Planck Institute for Marine Microbiology. Full text is online here or as a PDF.

Most of the other articles cover new tools for churning through your metagenomic sequence data and figuring out what is in there in terms of function and/or taxonomy. There are many approaches to this and several tools already out there including the very beautiful MG-RAST and Real Time Metagenomics. I have also been tinkering with these to explore the “pan-genomes” of various bacterial species where we have hundreds of genomes available… not quite what they were intended for but it seems to work quite nicely, and gives you some great insights into the spectrum of accessory genes that are flowing through various bacterial populations.

Enteroaggregative E. coli on LigerCat

Reading Jon Eisen’s blog this week I was rather taken with this post about LigerCat. LigerCat is an online tool that searches pubmed for whatever you ask it to, and displays a cloud of the MeSH terms (keywords attached to articles) associated with the pubmed results. It also shows a neat bar chart of article counts by year.

Since I’ve just been introduced to enteroaggregative E. coli thanks to the German E. coli outbreak, I thought I’d search for “Enteroaggregative E. coli”… this is the result.

I think this shows quite nicely that (at least according to the literature) this organism is defined by adhesion, normally associated with diarrhea in children and babies and commonly tested for by PCR.

According to this it was first described as enteroaggregative E. coli in 1989 and has been the subject of some attention, but not a lot, ever since (~15 articles per year):

The picture is quite different for “Shiga toxin“, most associated with E. coli O157 and hemolytic-uremic syndrome, with first mention in 1942 and a mass of interest since the 1980s, now with >200 papers each year: