Abstract
Many technologies have been developed to help explain the function of genes discovered by systematic genome sequencing. At present, transcriptome and proteome studies dominate large-scale functional analysis strategies. Yet the metabolome, because it is 'downstream', should show greater effects of genetic or physiological changes and thus should be much closer to the phenotype of the organism. We earlier presented a functional analysis strategy that used metabolic fingerprinting to reveal the phenotype of silent mutations of yeast genes1. However, this is difficult to scale up for high-throughput screening. Here we present an alternative that has the required throughput (2 min per sample). This 'metabolic footprinting' approach recognizes the significance of 'overflow metabolism' in appropriate media. Measuring intracellular metabolites is time-consuming and subject to technical difficulties caused by the rapid turnover of intracellular metabolites and the need to quench metabolism and separate metabolites from the extracellular space. We therefore focused instead on direct, noninvasive, mass spectrometric monitoring of extracellular metabolites in spent culture medium. Metabolic footprinting can distinguish between different physiological states of wild-type yeast and between yeast single-gene deletion mutants even from related areas of metabolism. By using appropriate clustering and machine learning techniques, the latter based on genetic programming2,3,4,5,6,7,8, we show that metabolic footprinting is an effective method to classify 'unknown' mutants by genetic defect.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 12 print issues and online access
206,07 € per year
only 17,17 € per issue
Buy this article
- Purchase on SpringerLink
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout



Similar content being viewed by others
References
Raamsdonk, L.M. et al. A functional genomics strategy that uses metabolome data to reveal the phenotype of silent mutations. Nat. Biotechnol. 19, 45–50 (2001).
Cramer, N.L. A representation for the adaptive generation of simple sequential programs. in Proceedings of the First International Conference on Genetic Algorithms and their Applications (ed. Grefenstette, J.J.) 183–187 (Lawrence Erlbaum, Mahwah, New Jersey, 1985).
Koza, J.R. Genetic Programming: On the Programming of Computers by Means of Natural Selection (MIT Press, Cambridge, Massachusetts, 1992).
Banzhaf, W., Nordin, P., Keller, R.E. & Francone, F.D. Genetic Programming: An Introduction (Morgan Kaufmann, San Francisco, 1998).
Langdon, W.B. Genetic Programming and Data Structures: Genetic Programming + Data Structures = Automatic Programming! (Kluwer, Boston, 1998).
Kell, D.B., Darby, R.M. & Draper, J. Genomic computing: explanatory analysis of plant expression profiling data using machine learning. Plant Physiol. 126, 943–951 (2001).
Kell, D.B. Genotype:phenotype mapping: genes as computer programs. Trends Genet. 18, 555–559 (2002).
Langdon, W.B. & Poli, R. Foundations of Genetic Programming (Springer, Berlin, 2002).
Fiehn, O. Metabolomics: the link between genotypes and phenotypes. Plant Mol. Biol. 48, 155–171 (2002).
Kell, D.B. & King, R.D. On the optimization of classes for the assignment of unidentified reading frames in functional genomics programmes: the need for machine learning. Trends Biotechnol. 18, 93–98 (2000).
Baganz, F., Hayes, A., Marren, D., Gardner, D.C.J. & Oliver, S.G. Suitability of replacement markers for functional analysis studies in Saccharomyces cerevisiae. Yeast 13, 1563–1573 (1997).
Oliver, S.G., Winson, M.K., Kell, D.B. & Baganz, F. Systematic functional analysis of the yeast genome. Trends Biotechnol. 16, 373–378 (1998).
Duda, R.O., Hart, P.E. & Stork, D.E. Pattern Classification, edn. 2 (John Wiley, London, 2001).
Hastie, T., Tibshirani, R. & Friedman, J. The Elements of Statistical Learning: Data Mining, Inference and Prediction (Springer, Berlin, 2001).
Oliver, S.G. Proteomics: guilt-by-association goes global. Nature 403, 601–603 (2000).
Breiman, L., Friedman, J.H., Olshen, R.A. & Stone, C.J. Classification and Regression Trees (Wadsworth International, Belmont, California, 1984).
Quinlan, J.R. C4.5: Programs for Machine Learning (Morgan Kaufmann, San Mateo, California, 1993).
Alsberg, B.K., Goodacre, R., Rowland, J.J. & Kell, D.B. Classification of pyrolysis mass spectra by fuzzy multivariate rule induction—comparison with regression, K-nearest neighbour, neural and decision-tree methods. Anal. Chim. Acta 348, 389–407 (1997).
Aranibar, N., Singh, B.K., Stockton, G.W. & Ott, K.-H. Automated mode-of-action detection by metabolic profiling. Biochem. Biophys. Res. Commun. 286, 150–155 (2001).
Griffin, J.L. et al. Metabolic profiling of genetic disorders: a multitissue H-1 nuclear magnetic resonance spectroscopic and pattern recognition study into dystrophic tissue. Anal. Biochem. 293, 16–21 (2001).
Goodacre, R., Vaidyanathan, S., Bianchi, G. & Kell, D.B. Metabolic profiling using direct infusion electrospray ionisation mass spectrometry for the characterisation of olive oils. Analyst 127, 1457–1462 (2002).
Martens, H. & Næs, T. Multivariate Calibration (John Wiley, Chichester, UK, 1989).
Jolliffe, I.T. Principal Component Analysis (Springer, New York, USA, 1986).
MacFie, H.J.H., Gutteridge, C.S. & Norris, J.R. Use of canonical variates in differentiation of bacteria by pyrolysis gas-liquid chromatography. J. Gen. Microbiol. 104, 67–74 (1978).
Windig, W., Haverkamp, J. & Kistemaker, P.G. Interpretation of sets of pyrolysis mass spectra by discriminant analysis and graphical rotation. Anal. Chem. 55, 81–88 (1983).
Manly, B.F.J. Multivariate Statistical Methods: A Primer (Chapman and Hall, London, UK, 1994).
Goodacre, R. et al. Rapid identification of urinary tract infection bacteria using hyperspectral, whole organism fingerprinting and artificial neural networks. Microbiology 144, 1157–1170 (1998).
Kell, D.B. Defence against the flood: a solution to the data mining and predictive modelling challenges of today. Bioinformat. World 1, 16–18 (http://www.abergc.com/biwpp16-18_as_publ.pdf, 2002).
Acknowledgements
This work was supported by a grant from the Biotechnology and Biological Sciences Research Council, UK, to D.B.K. and S.G.O., and by a grant from the Wellcome Trust to S.G.O. J.A. was the recipient of a BBSRC CASE studentship with Bayer CropScience (formerly Aventis CropScience). We thank John Pillmoor, Steve Dunn and Jane Dancer for their careful supervision, Bharat Rash and Nicola Burton of the Manchester laboratory for technical assistance and Roy Goodacre (Aberystwyth/UMIST) for useful discussions.
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Competing interests
D.B.K. and J.J.R. are directors of Aber Genomic Computing, whose software was used for one of the experiments described in the article.
Rights and permissions
About this article
Cite this article
Allen, J., Davey, H., Broadhurst, D. et al. High-throughput classification of yeast mutants for functional genomics using metabolic footprinting. Nat Biotechnol 21, 692–696 (2003). https://doi.org/10.1038/nbt823
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1038/nbt823