blog

A breathalyser for diagnosing disease sounds like something we’d expect to see on Star Trek. But work published in the British Journal of Cancer and evaluated by Christopher Janetopoulos suggests that such a thing might become not just possible, but affordable too. The ‘electronic nose’ detects volatile organic compounds¹ arising from the peroxidation of membrane compounds that often accompany tumour growth. The nanosensor array could also differentiate between different types of cancer.

X-ray crystallography and NMR are two often complementary techniques used to determine the structure of proteins. NMR is powerful for smaller proteins and for when a protein just won’t crystallized, and X-ray crystallography is often much quicker and can deal with huge complexes. But what about proteins that are too big for NMR (or insoluble) and won’t crystallize? A European team has developed a strategy for solid-state nuclear magnetic resonance² (ssNMR) spectroscopy that enabled them to solve the structure of amyloid fibrils, and published not just that structure but the associated difficulties and how they were overcome.

On the subject of protein structures, it’s often (if not usually) necessary to compare the structure you’ve just solved with the database of protein structures. While is is a pretty standard thing to do, comparing protein-protein interfaces can be just as important, but tools to do this are not so common. Enter iAlign, “a method for the structural comparison of protein–protein interfaces”³. The paper isn’t open access, but the software is available for free at https://cssb.biology.gatech.edu/iAlign (and there’s a web interface too). Me, I’m still hoping for the iSolve iPhone app.

Another couple of interesting evaluations of structural papers caught my eye this week, but we’re already a bit structure-heavy so I’ll just link to them: Charges in the hydrophobic interior of proteins and In vivo structure of the E. coli FtsZ-ring revealed by photoactivated localization microscopy.

Instead, I’ll leave you with an interesting little observation on a slightly older paper. Back in December, Chris Dobson’s group published in Science a theoretical treatment of the breaking of amyloid fibres⁴. Vincent Jansen queried the (possible) impression given in the original evaluation that the equations used were novel, and Dobson has responded. Quite aside from seeing post-publication peer review in action, it’s good to see the new F1000 website working properly!

Evaluated papers

1. Bad breath 10.1038/sj.bjc.6605810
2. Fibrillar NMR 10.1021/ja104213j
3. iAlign 10.1093/bioinformatics/btq404
4. Theoretical dissent 10.1126/science.1178250