Funding from the Chemical Sciences, Geosciences and Biosciences Division of the DOE's Office of Basic Energy Sciences provides $340,000 for operation and equipment this year and another $680,000 in 2006. Additional money is expected in 2007 and could continue if the program receives good marks during a peer review scheduled for 2008.
Before they can study the chemical makeup within plant cells, the team must construct new analytical instruments capable of identifying molecules in such minute quantities.
"Developing the instrumentation is a large part of the proposal and we're building a special, high-resolution mass spectrometer," Yeung said, "because there's nothing available commercially that meets our needs." He added that the equipment will be housed in the Roy J. Carver Co-Laboratory on the ISU campus.
Mass spectrometry works by measuring the mass of individual ions ?molecules that have been electrically charged. Plant material is ionized into a gas, sorted in an analyzer chamber according to the mass-to-charge ratios, and collected by an ion detector. The detector converts ion flux into a proportional electrical current. Finally, the magnitude of the electrical signals is recorded and plotted as a mass spectrum.
The ability to sort and detect these ions at cellular-scale quantities is where the team hopes to fine-tune the instrumentation.
Once the equipment is ready, the team will look at the chemical content in the cells of Arabidopsis thaliana, a small flowering plant that is widely used as a model organism in plant biology. Arabidopsis is a member of the mustard (Brassicaceae) family, which includes cultivated species such as cabbage and radish.
"Arabidopsis is not a major crop like corn and soybeans," Yeung said, "but because so much is already known about it genetically, we can hopefully begin to draw correlations between the chem