Research Abstracts Online
January - December 2011
University of Minnesota Twin Cities
College of Food, Agricultural, and Natural Resource Sciences
College of Science and Engineering
of Bioproducts and Biosystems Engineering
PI: Brett M. Barney
Understanding Proteome-Level Changes in Microbes Exhibiting the Phenomenon of Wax Ester Accumulation
Wax esters are long-chain carbon compounds that find application as fuel, lubricants, and essential components of various cosmetic products. Currently, most wax esters are petrochemical derivatives of non-renewable crude oil. Some renewable sources have not been sustainable for long-term development. The essentiality and enormity of uses associated with these chemicals serve to underline the importance of developing sources that are renewable and sustainable in the face of shrinking oil reserves.
Among the wide range of organisms that produce wax esters, bacteria that do so are the simplest to study. The best-studied bacteria that accumulate wax esters do so under conditions of nitrogen deficiency. Though the physiological function of such an action is unclear, the general consensus is that accumulation of wax esters is a carbon-storage mechanism. The goal of this project is to understand the system-wide changes in the proteome of model bacteria that exhibit the phenomenon of wax ester accumulation.
The volume of wax esters produced by the bacterial cell is significantly higher during conditions of nitrogen starvation, when all other media components are identical. Since biological wax esters are derived from carbon-rich fatty acids, it is like that increased production of wax esters could result from a significant impact on the regulation of carbon and nitrogen fluxes through the cell. Thus, by comparing quantitative proteomic data from bacteria grown under differential nitrogen availability, these researchers expect to see how the proteome shifts the carbon flux towards increased wax-ester production. Understanding this process would be a key step in the rational metabolic engineering of microorganisms for sustainable wax-ester biotechnology.
Rachel Mann, Graduate Student
Nagendra Palani, Graduate Student