Barry Douglas Bruce - US grants

9401840 Bruce, Barry, D. This is a start-up grant for a Post Doctoral Fellow in Plant Biology. In plants and other eukaryotes, the translation of nuclear encoded genes can be divided into two diverging pathways: one, where proteins are translated on ribosomes associated with the endoplasmic reticulum and are destined either for the ER/Golgi complex for secretion, or for the plasma membrane; and a second pathway, where proteins are synthesized on free ribosomes in the cytoplasm. In plants, proteins synthesized on free cytoplasmic ribosomes can either remain in the cytoplasm, or being imported into one of four different organelles: the nucleus, the peroxisome, the mitochondria or the chloroplast via a post translational pathway. This post translational import requires a precursor form of the protein containing a targeting sequence which directs it to a specific organelle. It has been proposed that one prerequisite for the import of these precursors is that they maintain an import competent configuration. It is commonly accepted today that import of proteins into mitochondria requires that they be in a destabilized conformation. The role of protein conformation on import into chloroplasts is much less certain. The goal of this proposal is to determine what defines the import competence of chloroplast targeted precursors, and also what cytosolic factors are involved in maintaining this competence. The small subunit of ribulose bisphosphate carboxylase has been chosen as a model to address this question. The investigation will focus on purification of cytosolic factors that interact with the transit peptide for chloroplastic transport; on identification of trans-acting chloroplast import factors by the two-hybrid cloning technique, that allows specific protein-protein interactions to be identified in vivo through the reconstitution of a transport activator; and assaying in vitro the soluble factors in increasing import competence of the precursor of the sma ll subunit of ribulose bisphosphate carboxylase. %%% The PI made good progress during his post doctoral research on the problems concerning protein import into organelles, and obtained results which suggest that the conformational requirements for chloroplast import and mitochondrial import may be different. The goal of this project is to investigate the specific requirements for protein transport into chloroplasts. This is the topic that the PI started during his post doctoral research in the Keegstra laboratory. He will be taking the project with him to the University of Tennessee at Knoxville, where he starts a tenure track position in January 1994. This start-up grant for NSF Post Doctoral fellows in Plant Biology therefore will be essential to help him establish his own laboratory, and also scientific status. ***

This proposal leading to this award was received in response to Nanoscale Science and Engineering initiative, NSF 03-043, category NIRT. The award will support the joint efforts of investigators at the University of Tennessee and the Massachusetts Institute of Technology who will explore the use of naturally occurring photosynthetic complexes to produce an efficient photovoltaic device (solar cell). Conventional silicon-based (inorganic) solar cells remain costly and energy intensive to manufacture. This has limited the use of photovoltaic devices to much less than 1% of the worldwide supply of energy. Preliminary work by the investigators has shown that bacterial photosynthetic systems, whose overall quantum is nearly 100%, can be joined to amorphous organic semiconductors to produce a functioning device. Although this device has low efficiency, work on stabilization of the membranous structures that hold the photosystem components is expected to lead to devices whose power conversion efficiency can match or exceed that of the best existing silicon-based photovoltaic devices. If successful, this effort could eventually lead to the production of inexpensive solar cells that are flexible and lightweight, and that perform competitively with inorganic semiconductor cells. In addition to these research efforts, the investigators will undertake a multi-tiered education strategy that targets graduate and undergraduate students through research involvement and a variety of graduate-level courses. Outreach efforts aimed at middle school students and their teachers are also planned.

Plastids have evolved into semi-autonomous organelles whose metabolic function is heavily dependent upon the import of nuclear-encoded proteins that were initially encoded by ancestral cyanobacterial genomes. The majority of nuclear-encoded proteins that function within the plastid are synthesized as higher molecular weight precursors with an N-terminal extension known as a transit peptide, which mediates specific and efficient targeting of the precursor to plastids. Analysis of the Arabidopsis genome predicts that more than 3000 precursors are plastid-targeted. The structural and functional criteria that define these thousands of transit peptides are not well understood. Analysis of hundreds of transit peptides to date has failed to reveal significant conserved primary sequence, suggesting that a common secondary or tertiary structure may account for the specific targeting activity of transit peptides. In this study, site-directed molecular mutagenesis, NMR, isothermal titration calorimetry, and analytical ultracentrifugation will be used to directly determine the structural basis of peptide-receptor interactions in Arabidopsis. This project will provide a new level of mechanistic understanding of chloroplast protein import. Findings from the project will provide a starting point for additional structure/function analysis of other transit peptides and their interaction with other components of the chloroplast translocation apparatus. An applied aspect of this research may be the enhanced targeting of novel plastid precursor proteins to plastids, thereby improving both the utility and safety of many different agronomic plants and plant products.

Given the impending global energy/climate crisis, engineering practice must undergo a paradigm shift from a traditional design process that had little regard to energy and/or environmental costs to a new process that must address a broader set of parameters that include the ultimate sustainability of the design alternatives. This Integrative Graduate Education and Research Traineeship (IGERT) program will provide the resources for the University of Tennessee to become a national curriculum and research leader in sustainable energy technologies by developing the technological, scientific, and engineering expertise required. The training of scientists and engineers must now change in two important ways. First, engineers must now learn to work within the context of sustainable production processes. Second, engineers must now learn to work regularly on complex innovative production processes that require advanced interdisciplinary expertise and collaboration of materials, computational and biological sciences and engineering. This IGERT provides a highly integrated engineering curriculum and training program with a coherent sequence of steps toward the proficiency required to work effectively in the sustainable energy arena. The program fosters the development of technological, scientific, and engineering expertise required in exploring new, sustainable energy technologies. The diverse trainees will have expertise in either biomolecular engineering or materials science and engineering relevant to sustainable production of energy; breadth in both the biomolecular and materials disciplines; pervasive exposure to research performed within the context of sustainability; and a commitment to outreach through workshops at the American Museum of Science and Energy in Oak Ridge and Knoxville ASM Summer Materials Camp. IGERT is an NSF-wide program intended to meet the challenges of educating U.S. Ph.D. scientists and engineers with the interdisciplinary background, deep knowledge in a chosen discipline, and the technical, professional, and personal skills needed for the career demands of the future. The program is intended to catalyze a cultural change in graduate education by establishing innovative new models for graduate education and training in a fertile environment for collaborative research that transcends traditional disciplinary boundaries.

CBET-0828615
Frymier

Toward the end of this century, the production rate of petroleum will have reached its peak and the supply will begin to decline. In the mean time, the combustion of fossil fuels generates carbon dioxide and nitrogen oxides, with the potential to significantly affect the global climate. How will we as scientists, engineers and educators address this new challenge and others like it? How should we be preparing the next generation of scientists and engineers to solve problems in a resource limited world, where they will need to assess the environmental sustainability of technologies to meet energy and resource needs? To this dual challenge, we present a single solution that is built around the Sustainable Photosynthetic Hydrogen Evolution Research (SPHERE) program.

This research involves the development of a 1st generation fully functional sustainable process based on a Sustainable Photosynthetic Hydrogen Evolving Research-Improved Complex (SPHERIC) device that would take the dilute energy of the sun and, using only water, produce a concentrated, environmentally benign fuel. To develop this process requires the solution of several challenges. First, photosystem I (PSI), suitable electron transfer mediators, and a suitable hydrogenase must be purified/cloned from their host organisms. Next using molecular biology these proteins must be made to work together, outside of their host organisms and engineered to produce H2 at a sufficiently high rate. While a sustainable process would contain all four elements, in this proposal we will first tackle the problem of accelerating the transfer of electrons from cytochrome c553 through PSI, to the hydrogenase enzyme where H2 will be produced (although this reaction will use ascorbate as an electron source, future work will try to utilize the H2O splitting of PSII). We propose to accomplish this goal in a series of steps with multiple routes to success. Specifically, we will 1) increase the interaction of cyt c553 with PSI via three strategies, 2) select, clone and characterize oxygen and thermotolerant hydrogenases, and 3) couple the appropriate hydrogenase with PSI in vitro and in vivo.

In order to meet current and future challenges to sustainable processes for fuel and chemicals production, we need to train engineers to take cues from biology for potential solutions and to train scientists to apply engineering design and analysis principles to biological processes. Our previous experience has shown us the value of teams of students, formed with appropriate regard to academic, ethic and cultural diversity, in solving design problems posed at the interface of biology and engineering. We will pursue three initiatives to address the educational challenges of developing sustainable solutions: 1) Recruit highly qualified undergraduates from underrepresented populations to work in groups on the development of solutions to resource and energy problems within a context of sustainability. 2) Develop a collection of challenge problems targeted at high school and lower division undergraduate students that emphasize sustainability analysis for energy and resource alternatives, 3) Advise the students in producing a biweekly podcast that highlights the current and dynamic landscape of research in areas with application to sustainable energy.

Proposal Number: EPS-1004083

Proposal Title: Tennessee Solar Conversion and Storage using Outreach,
Research and Education (TN-SCORE)

Institution: University of Tennessee Knoxville

This first Research Infrastructure Improvement (RII) Award to the state of Tennessee would expand and enhance the physical, personnel, and cyberinfrastructure at academic institutions. The RII program builds on the momentum generated by the state government's investment in clean energy sector for economic development and the recent hiring of eminent faculty members in energy related areas in the University of Tennessee system. The RII program entitled "Tennessee Solar Conversion and Storage Using Outreach, Research and Education (TN-SCORE)" would leverage state investments, build partnerships for research and educational activities among ten higher educational institutions across the state, and provide meaningful research experience to secondary school teachers and students.

Intellectual Merit
The RII program is focused on energy research and education involving nine geographically distributed colleges and universities in Tennessee and strengthens collaborations between academic institutions and Oak Ridge National Laboratory. Research focus centers around three thrust areas: (1) Sustainable methods and materials for solar energy capture and conversion; research is on photovoltaic cells fabricated using thin Si films, hybrid organic-semiconductors, and novel biomaterials. (2) Electrochemical energy conversion (fuel cells) and storage (batteries) devices. (3) Development of novel nanostructures and nanomaterials to enhance energy efficiency in the areas of solid state lighting and solar energy conversion. The facilities available at the University of Tennessee Knoxville, Vanderbilt University, and Oak Ridge National Laboratory are leveraged to address the challenges in the development of renewable and environmentally clean energy sources and advance the current status of the field.

Broader Impacts
The implementation of this RII program would establish a robust infrastructure for research and educational collaboration across the state of Tennessee. The project would help build Tennessee's capacity for national competitiveness in alternative, renewable energy arena. The project would create new collaborations among Universities and colleges in Tennessee and with Oak Ridge National Laboratory. These partnerships would help eliminate geographical parochialism which is identified as one of the barriers to fully develop the state's capabilities in Tennessee Science and Technology Plan. The program involves students at all levels and thus would prepare a well-trained workforce in renewable energy related areas. Plans to develop a road show and news items on energy research for general audiences would inform the public about the importance of basic research and energy related issues.

An award is made to the University of Tennessee Knoxville to support the acquisition of a transmission electron microscope (TEM) for the Advanced Microscopy and Imaging Center. The new TEM will be equipped for dual-axis electron tomography, which creates an unprecedented view of the three-dimensional cellular organization. The system will also be equipped with a high-resolution camera to provide a shared platform for diverse innovative projects that depend on advanced imaging capabilities. Most of the research on this instrument will be carried out by graduate students and postdoctoral researchers who will gain expertise in modern techniques of high-resolution imaging. The new system will also be the core instrument for advanced imaging course, where students receive research training with significant hands-on time on the TEM.

The new instrument will support research projects aimed at deciphering the formation of cell-cell connections in plants, understanding the interactions between bacteria and their animal or plant hosts, and how chromosomes move during different parts of the cell cycle. Other projects will investigate the molecular mechanism of protein import into different cell organelles, or analyze the morphology and assembly of viruses. Researchers in the Chemistry Department will use the instrument to study the nanostructure of advanced materials with a wide range of potential applications. Results from these studies will be published in peer-reviewed scientific journals, presented at scientific meetings, and used in public outreach or education events.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.