Hydrogen gas (H2) is growing in demand as an energy resource. It is currently produced from non-renewable sources, which is both costly and environmentally harmful. With this award, the Chemistry of Life Processes Program in the Chemistry Division is funding Dr. Alexey Silakov from Pennsylvania State University at University Park to study a recently discovered bacterial enzyme that contains two iron atoms. This [FeFe] hydrogenase molecule speeds up chemical reactions so that they can efficiently produce H2 gas that can be used as an energy resource. Current, [FeFe] hydrogenases lose their activity upon exposure to even small amounts of oxygen (O2) from the air, hampering their industrial use for energy production and utilization. The [FeFe] hydrogenase employed by the Silakov group remains stable and active after O2 exposure. Dr. Silakov will apply structural and computational approaches to help explain why this [FeFe] hydrogenase is O2 tolerant, setting the stage for their use in environment-friendly and renewable hydrogen production and energy generation. This research project provides graduate and undergraduate students with opportunities to develop experimental and theoretical skills that are critical for their future careers in the sciences. In addition, Dr. Silakov develops lectures and hands-on training in research methods used to study enzymes as a part of the University’s biannual Bioinorganic Workshop. Finally, Dr. Silakov engages high-school students from under-served communities by developing curricular materials on the hydrogen-based economy and by providing laboratory experiences to foster their interest in pursuing careers in STEM fields.
In this project, Dr. Silakov investigates a putative subclass of highly O2-tolerant [FeFe] hydrogenases. The discovery these [FeFe] hydrogenases sets a new paradigm for the stability of these highly efficient enzymes in the presence of oxygen. By studying structures of the O2-tolerant [FeFe] hydrogenases and physicochemical properties of the incorporated metallocofactors, this project establishes the connection between the enzymatic function, mechanisms of safe reaction with O2, and the structural determinants of specific phenotypes. The multidisciplinary research plan encapsulates advanced electron paramagnetic resonance and vibrational spectroscopies, electrochemistry, X-ray crystallography, molecular dynamic simulations, and quantum chemical calculations. This research formulates the structure-function relationships that are instrumental for engineering hydrogenases to perform a particular function and provides an in-depth understanding of how different components of the metal-containing enzymes work together. This project builds a rich platform to engage a diverse group of scientists from high-school to graduate students in STEM activities through a series of outreach activities.
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.
