The recent explosion in genome data was made possible by 20-years of advances in analytical chemistry, which increased the cost-efficiencies of DNA sequencing technologies. Similar technological advances are now required to more efficiently characterize the functionality of an organism’s genetic potential. The Nikolau group is developing metabolomics as a functional genomics tool to decipher metabolic and physiological functions of genes of unknown function. For example, the Arabidopsis Metabolomics Consortium has determined the metabolome of Arabidopsis and how its affected by T-DNA-tagged mutants to evaluate the consequence of the loss-of-gene function on the metabolism of the organism.
However, dissecting metabolic processes in a multicellular organism requires the observation of metabolites among and within individual cellular structures. The Nikolau group is collaborating with Drs. Young-Jin Lee, ISU Department of Chemistry, to develop high spatial resolution metabolite imaging techniques using mass spectrometry. For example, single cell level spatial resolution of ~5 μm has been achieved by using laser beam induced ionization of molecules on the surface of plants, and these have been analyzed with a MALDI-LTQ mass spectrometer.
Additional technological advances are being developed by the acquisition of new instruments that will be housed at the WM Keck Metabolomics Research Laboratory. These include:
- Agilent Technologies GCxGC-MS, which has the ability to conduct orthogonal separation of analytes by gas chromatography, providing a means of evaluating low-abundance analytes in very complex mixtures. This technology is being applied to the characterization of plant nectars.
- Programmable Temperature Vaporizer Inlet Injector for gas chromatography. This device offers the means for analyzing very dilute samples, by providing the ability to concentrate samples during the injection process. This technology is being applied to the analysis of micro-samples, such as single Arabidopsis flowers and seeds.
- The Bruker Daltonics solariX™ FTMS system. This high-resolution instrument can determine the mass of ions to an accuracy of less than 1ppm, which will enhance the ability to chemically define analytes.
Present researchers
Liza Alexander, PhD student, Molecular, Cellular & Developmental Biology
Keting Chen, PhD student, Bioinformatics & Computational Biology
Ann Perera, scientist and manager, WM Keck Metabolomics Research Laboratory
Bo Xie, associate scientist
Past researchers
Julia Reiman, undergraduate student, Biological Systems Engineering
Jennifer Robinson, MS student, Biochemistry
Lucas Showman, postdoctoral research associate
Zhihong Song, associate scientist