We work at the interface between Biology, Chemistry and Mathematics, and most of projects have a metabolomics or proteomics flavour to them.

Mass spectrometry for high-throughput metabolomics
The MS-based gold standard for metabolomics is GC-MS. However this is slow and laborious since it requires chemical derivatisation and complicated deconvolution. By contrast, we have been developing direct infusion ESI-MS (electrospray ionisation) via flow injection for metabolic profiling; but, in the general case, ion-suppression effects limit the utility of this approach. We are therefore now concentrating on developing direct laser desorption ionisation-MS that requires no matrix, and which would thus allow the very high throughput analysis of cell extracts spotted onto appropriate plates and analysed in a standard MALDI-MS instrument.

Integrative ’omic analyses for understanding biological systems
Improving the stability of whole cell biocatalysts would allow a much wider range of redox enzymes to be exploited to manufacture speciality chemicals and pharmaceuticals. However, this is an extremely complex task, since a large number of genes (many unidentified) interact to determine biocatalyst performance in the presence of toxic process materials. We are using a systems biology approach to identify and rank the importance of the genes determining biocatalyst stability.

Development of a wide variety of Raman spectroscopic methods
Raman spectroscopy is a method that measures the inelastic light scattered from a monochromatic light source. It is attracting great interest with biology because it is non-destructive and gives chemical information about the sample under investigation. However, the ‘normal’ Raman effect is very weak, since typically only 1 in every 10⁸ photons exchange energy with a molecular bond vibration, the rest of the photons being Rayleigh scattered. Consequently data acquisition for spectra from biological samples with a suitably high signal-to-noise ratio still often takes 5-15 min. Thus we are concentrating on enhancing the Raman signal via surface enhanced Raman spectroscopy (SERS) and deep UV resonance Raman spectroscopy (UVRR).

Metabolomics and proteomics in health and disease
Metabolite and protein profiling are emerging as very powerful methods to study disease processes and we are investigating the potential of these methods both temporally and spatially.  Projects include:
(a) Monitoring the fate of pharmaceuticals in marine and freshwater environments by assessing the impact of pharmaceutical exposure on the metabolome of ecologically important groups of microbes in terms of the biochemical pathways by which drugs undergo degradation and the biodiversity of microbial communities.
(b) Investigating various methods that produce chemical maps that can be used for imaging for chemical pathology.  These methods include mass spectrometry for proteomics, whilst for metabolomics FT-IR and Raman spectroscopies are being developed.
(c) Finally, we are also investigating MALDI-MS and UVRR spectroscopy for predicting human diseases from serum and for biomarkers discovery.

Rapid characterisation of microorganisms
In view of the increasing prevalence of microbial infections and the expanding ability of such organisms to acquire (multiple) resistance(s) to antimicrobial agents, there is a continuing need for the rapid characterisation and speciation of bacteria and fungi. We are developing a wide variety of analytical instrumentation-based approaches often referred to as ‘whole-organism fingerprinting’ for the rapid identification of bacteria and fungi. We are particularly interested in methods based on ESI-MS and MALDI-MS, Fourier transform infrared (FT-IR) spectroscopy and Raman spectroscopy.
This is a general theme that we have been working on for the last 15 years and touches on all of the above.

Rapid characterisation of foodstuffs
Foods (either muscle food (e.g., meat, poultry and seafood), vegetables, or refined products (e.g., fruit juices)) are described as spoiled if organoleptic changes make them unacceptable to the consumer. Spoilage is generally a result of decomposition and the formation of metabolites resulting from the growth of micro-organisms. It is important to both the retailer and consumer that any spoiled food be removed from sale and the contaminating organism be identified as either a pathogen or a 'harmless' saprophyte.  We have been investigating FT-IR spectroscopy for the quantitative analysis of food spoilage
In addition, there is a continuing requirement for rapid, accurate, automated methods for determining whether a particular foodstuff has the provenance claimed for it or whether it has been adulterated with or substituted by a lower-grade material. This is also an area where analytical biotechnology can play a part and over the years we have been investigating the adulteration and origin of a wide variety of foods including olive oil, orange juice, cocoa butter and honey.
This is a general theme that we have been working on for the last 10 years and touches on all of the above.

Last updated 02 February 2005