Dr Tony Fawcett
My interests lie in understanding the organisation and regulation of complex metabolic events. Current work is in two biological systems, with primary focus being in the synthesis of fatty acids and lipid in plants.
De novo fatty acid synthesis takes place in plastids, using two enzyme systems; acetyl-CoA carboxylase and fatty acid synthase (FAS). The type II FAS, of plants, is composed of separate soluble enzymes that each carry out a single enzymatic reaction with the growing acyl chain being attached to acyl carrier protein (ACP). The major destination of newly synthesized fatty acids, in seeds, is storage triglycerides, which are mobilized to release energy during seed germination, but also have an important agronomic value as a source of cooking oil. The synthesis of storage oil in plant seeds is analogous to a factory production line, where the supply of raw materials, manufacture of components and final assembly can all potentially limit the rate of production. Recently, we made a first experimental study of overall regulation of storage oil accumulation in oilseed rape, which we analysed by a mathematical method called flux control analysis. This analysis showed that it is final assembly that is the most important limitation on the biosynthetic process. Future work will dissect the assembly block of enzymes to guide future crop improvement strategies for increased oil production.
My second area of interest is the relationship between the cell wall synthetic enzymes of Gram-positive bacteria and antibiotic resistance. Bacterial cell walls are complex polymers of sugars and amino acids that are important in determining cell shape and cell integrity and their synthesis requires the action of many different enzymes. Some of these enzymes are targets for well-known antibiotics, including the penicillin family. Using laboratory-generated strains of Staphylococcus aureus we are investigating what changes in the proteome and genome result in penicillin and methicillin resistance in the absence of the classical mecA resistance gene.
- Bacterial cell wall biochemistry
- Plant lipid biochemistry
Journal papers: academic
- Tang, Mingguo Guschina, Irina A. O’Hara, Paul Slabas, Antoni R. Quant, Patti A. Fawcett, Tony & Harwood, John L. (Published). Analysis of lipid accumulation in developing oilseed rape (Brassica napus L. cv. Westar) embryos reveals that flux control is distributed differently from that in oil fruits. New Phytologist 196(2).
- Tang, M., Guschina, I.A., O’Hara, P., Slabas, A.R., Quant, P.A., Fawcett, T. & Harwood, J.L. (2012). Metabolic control analysis of developing oilseed rape (Brassica napus cv Westar) embryos shows that lipid assembly exerts significant control over oil accumulation. New Phytologist 196(2): 414-426.
- Mina, J.G., Okada, Y. , Wansadhipathi-Kannangara, N.K., Pratt, S., Shams-Eldin, H., Schwarz, R.T., Steel, P.G., Fawcett, T. & Denny, P.W. (2010). Functional analyses of differentially expressed isoforms of the Arabidopsis inositol phosphorylceramide synthase. Plant Molecular Biology 73(4-5): 399-407.
- O'Hara, Paul., Slabas, Antoni R. & Fawcett, Tony. (2007). Antisense expression of 3-oxoacyl-ACP reductase affects whole plant productivity and causes collateral changes in activity of fatty acid synthase components. Plant and Cell Physiology 48(5): 736-744.