Thursday, December 03, 2009

Jake Bundy

What's your position and where are you working?
For the past 5 years I have worked as a lecturer in Biological Chemistry in the section of Biomolecular Medicine at Imperial College London.

Where have you been working before?

Before this, I post-doc’ed at Cambridge; before that, UC Davis; and before that, for my first post-doc, at Imperial College again.

Briefly describe your research.
I am interested in metabolism in invertebrate and microbial species, and how this is involved in several different biological questions. Some of the projects I currently work on include microbial virulence and pathogenesis; how metabolism is affected by problems with recombinant protein folding in the bioprocessing yeast Pichia pastoris; and using earthworms as biomonitors of environmental pollution.

What do you use NMR for?
Together with mass spectrometry, I use NMR for metabolite profiling, as part of the technology for metabolomic studies. Although it’s generally less sensitive than mass spec, NMR still has a very useful role – as a near-universal and robust detector, it can give a quick and information-rich spectral profile. Most of the work we do, we just use 1D NMR for profiling; particularly useful for studies where you want to process as many samples as possible. However there are also other cases where more in-depth NMR experiments are needed, for example for isotopomer analysis to investigate metabolic fluxes; or to assign novel metabolites (essentially a natural products chemistry problem).

Which NMR software are you using?
XWIN-NMR and Topspin for data acquisition; iNMR for all NMR processing. I also use Chenomx NMR Suite for helping assign and quantitate metabolites in NMR spectra.

Which other NMR software have you used in the past?

I’ve also used VNMR and ACDLabs NMR software, and MestreC (before it was released as a commercial product).

How do you rate iNMR?
iNMR is not only my favourite NMR software for Mac OS (I’m not sure how many competitors there are at the moment), but it’s easily my favourite NMR software full stop. It’s one of a handful of Mac-only packages that I use all the time as part of my regular working day (others include Papers, Aabel, and Bookends). Features that I particularly like include the Overlay Manager (which makes it by far the quickest and easiest NMR software to use for comparing multiple spectra, in my opinion), and also the overall simplicity of using it to produce quality spectral images that can go straight into a paper or presentation without having to use multiple machines or virtualization. I admit I wasn’t really bothered by lack of anti-aliasing on spectra before using iNMR, but now I’m used to it, I do find it genuinely annoys me when looking at spectra in Topspin, say – it’s distinctly harder to see fine detail without zooming in. It’s also elegant and quick – not essential properties for software, but makes it more enjoyable to use on a regular basis.

Is it enough for your needs?
Well, it’s certainly enough for my needs in the sense that all of the spectra that I acquire are processed with iNMR – so in one sense, yes, almost by definition. It’s not 100% perfect though, there are still some small issues that could be ironed out in future releases – and as I’ve already said, I do use Chenomx software for some complementary uses which iNMR isn’t primarily designed for. I definitely see it as a crucial part of my workflow for the foreseeable future though, and expect it will keep improving (although by now it’s a relatively mature product).

Wednesday, December 02, 2009

Hands on 3-D Processing

A measure of the computing power available today with a desktop computer is the possibility of processing huge spectra in real time. For example: is it possible to correct the phase of a 3-D matrix interactively, in real time? The answer is: yes and you don't even have to employ more than a single core nor to buy an high-end graphic card. When I mean interactive processing I mean that:
- you see a graphic representation of the matrix at each processing stage.
- you can play with it, for example change a parameter just to see the effect it has on the matrix.
It is always necessary to know and understand the mathematical rules that govern NMR processing. The more you know them the more you enjoy their visual representations. The more you play with the graphics, the more you understand the maths behind. The two things go together.
You can find a self-teaching course on basic 3-D processing on the iNMR web site. There is no theory, only a lot of examples and a good measure of practical tips.