RESEARCH FOCUS

Our lab studies microbial extremophiles primarily hyperthermophiles including members of the archaeal and bacterial domains. Sulfolobus solfataricus and related species are thermoacidophilic organisms belonging to the Archaea. Much of our work on them focuses on adapatations to life at high temperature, bioprocessing and chromatin. Metallosphaera sedula another archaeon, is the focus of studies on biotransformations of metal again at temperature extremes. Finally the thermophilic anaerobe, Thermotoga maritima, is the focus of studies on hydrogen metabolism. The main approach used in our lab is a functional genomics approach based on the creation and application of genetics systems coupled with bioinformatics. While molecular biology methods are a mainstay, additional efforts include the use of bioreactors, protein purification and metabolomics.

Value-Added Products from Renewable Biofuels – DOE EERE OBP
The goals of the research project are to investigate the utility of single extremophiles and their enzymes to accelerate lignocellulose processing. Pretreatment inhibitors will be identified and mitigated and metabolic engineering will be used to block consumption of liberated monosacharides to preserve carbon for subsequent ethanol biosynthesis. Finally, addition of expanded deconvolution traits will be examined as a further step to improve overall process performance. This project will address DOE-EERE identified barriers within the “Biochemical Conversion” area including i) Bt-F Cellulase Enzyme Production Costs; ii) Bt-H Enzyme Biochemistry; and iii) Bt-J Fuels Organism Development. These Barriers are relevant to Milestone 5, Perennial Crop Processing Pathway Milestones. The perennial crop will be switchgrass, Panicum virgatum, along with annuals corn stover and wheat straw.
 
See http://nuenergy.unl.edu for more information

Biohydrogenesis in the Thermotogales --  DOE BER
The production and consumption of molecular hydrogen drives the physiology and bioenergetics of many microorganisms in hydrothermal environments. As such, the potential of these microorganisms as model systems to probe fundamental issues related to biohydrogen production merits consideration. Specifically, it is important to understand how carbon/energy sources relate to the disposition of reducing power and, ultimately, the formation of molecular hydrogen by high temperature microorganisms. This project will focus on bacteria of the thermophilic order Thermotogales, fermentative anaerobes that produce H2 from simple and complex carbohydrates.  A combination of metabolomics, genomics and genetics will be used to interrogate the Thermotoga system to expand understanding of biohydrogenesis.

Uranium Mobilization by Extremely Thermoacidophilic Archaea – DOD DTRA
Uranium use for nuclear power generation is approaching 60,000 tons/year and may double by 2030. Global reserves of recoverable uranium are estimated to be 5.5 megatons, 25-35% of which is associated with mineral sulfides. Recovery of uranium from these ores, if technically and economically feasible, could supplement conventional sources for energy production needs. Uranium bioleaching processes have neither benefited from developments in molecular biotechnology and genomics nor from the use of novel microorganisms that could offer improvements. Extremely thermoacidophilic archaea have been isolated that offer potentially significant advantages over mesophilic bacteria in terms of bioleaching rates and yields. To achieve this goal molecular genetics and functional genomics tools will be used to examine species from the extremely thermoacidophilic genus Metallosphaera for their capacity to mobilize uranium from low-grade, pyrite-bearing ores.  Consequently this study will assess the potential for high temperature, microbially-based uranium recovery processes.

Integration of Microbial Communities into a Microbiology Laboratory Class Curriculum – NSF -- DUE
The biology of microbial communities is an area of rapid growth centered within the larger discipline of microbiology. Key niches harboring these communities include; soils, rocks, foods, potable and wastewater, and the endogenous and invasive flora of plants, animals and humans. Newly developed research methods using molecular strategies have transformed microbial community analysis into an accessible research topic. Despite such advances, transmission of this topic into pedagogical form has lagged behind. This project will translate existing research-based methods for microbial community analysis into an instructional microbiology laboratory module. The proposed module will expand the undergraduate experience from pure culture to community culture microbiology.

Research Experience for Undergraduate Site: Integrated Development of Bioenergy Systems NSF-- DOD
This University of Nebraska-Lincoln REU site will provide a research experience for undergraduates during the summers of 2009 thru 2011. The program focuses on bioenergy research using microbes or plants. Ten students will have a hands-on research experience in one of twelve laboratories under the guidance of an experienced faculty mentor. Students will receive a stipend for 10 weeks (June through mid-August). On-campus housing, travel to and from the lab, access to health services, and other minor costs are provided at no cost to participants. Research will be coordinated with seminars, lunches, career guidance, industrial exposure, group activities, and a research symposium. Students will get training in biochemistry, molecular biology, genetics, and the physiology of selected model systems. They will engage in a debate on how to achieve sustainable energy supply for meeting a key national challenge. Upon completion of the REU program, students will be fully prepared for future opportunities as researchers in bioenergy, including graduate education. The program is open to all undergraduate students enrolled in biology, chemistry, or engineering. Underrepresented minorities and students from colleges with limited research opportunities are encouraged to apply.

See  http://www.unl.edu/summerprogram/program_bioenergy.shtml for more information.