systems that directly produce solar fuels better than plants do to avoid having to use plants. Rohlfing presented three examples of research sponsored by BES that demonstrate how chemistry relates to dynamics and change.

First, the Fenna-Matthews-Olson, or FMO, complex is a bacteria-chlorophyll complex that acts as a photosynthetic system (Figure 2.1). It is a conduction device for transporting the electrical energy when harvesting light. Researchers are trying to determine how energy is transferred along the set of chlorophylls. Is it by energy hopping or is there some more complex physical process? Coherent spectroscopy based on a femtosecond photon-echo technique in the visible region of the spectrum was applied to the FMO complex to determine whether there is quantum coherence (quantum beats) in the system. Quantum coherence is important because it helps avoid kinetic traps, explained Rohlfing.

The second example of research being funded by DOE involves a model system, metalloporphyrin, which looks at excited-state evolution using time-resolved X-rays. This research sets the groundwork for future research that will be conducted on much shorter time scales than the femtosecond domain.

The third research project presented by Rohlfing looked at the intrinsic motions of proteins as they influence catalysis and enzymes. Characterizing the intrinsic motions of enzymes is necessary to fully understand how they work as catalysts. As powerful as structure-function relationships are, the motion of these proteins is intimately connected with their catalytic activity and cannot be viewed as static structures. This realization, asserted Rohl fing, could revolutionize and accelerate approaches to biocatalyst design or directed evolution, and could alter understanding of the relations between protein structure and catalytic function.


The next speaker was Michael Clarke of NSF’s Chemistry Division. He explained that the NSF funds a broad range of science and that the agency is concerned about making energy sustainable and solving the carbon dioxide problem.

Next he discussed the method that NSF uses to fund the scientific research. It has a program that was originally called the Chemical Bonding Centers but is now morphing into Centers for Chemical Innovation, which makes a number of relatively small awards, around $500,000, to fund groups of

FIGURE 2.1 Model of the photosynthetic apparatus (Fenna-Matthews-Olson complex) in Chlorobium tepidum.

SOURCE: Donald A. Bryant, The Pennsylvania State University, and Dr. Niels-Ulrik Frigaard, University of Copenhagen.



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