About the Speaker:

Education:

Ph.D., Physical Chemistry, Heinrich-Heine-Universität Düsseldorf/ Max-Planck Institute for Bioinorganic Chemistry, Germany, 2007

M.S., Physics, Kazan State University, Russia, 2003

Research:

Our lab’s research interests lie in the interplay between bioinorganic chemistry, physical chemistry, and structural biology. By establishing novel spectroscopic methodologies, we aim to provide the most complete electronic and structural information concerning the catalytically active (metal) centers and delineate the intricate mechanisms of biological systems that are of interest to medical and renewable energy fields.

Establishing the relation between the structure and the function is one of the key problems in enzymology. Resolution of this fundamental issue allows us not only to understand the inner working of a specific system but also to provide a basis to predict functionality in other, yet to be explored, proteins.

Another goal of our research is to develop high-sensitivity and versatile electron-paramagnetic resonance techniques that would provide structural information about biological systems such as proteins, DNA, and RNA in vitro and/or in vivo which could also be used to study the interaction between such biological entities.

About the Seminar:

Title:

Investigating an unexpected high tolerance to dioxygen in [FeFe] hydrogenases

Abstract:

[FeFe] hydrogenases catalyze reversible hydrogen evolution at rates as high as 10,000 turnovers per second. This exceptional catalytic ability is attractive for the use of hydrogenases in renewable energy applications and biohydrogen production. Unfortunately, these enzymes degrade irreversibly upon exposure to minute amounts of oxygen, presenting major roadblocks for study and implementation in practical or industrial applications. The recent finding of an oxygen-tolerant [FeFe] hydrogenase from Clostridium beijerinckii (CbHydA1) is a long-awaited breakthrough in the field of enzymatic hydrogen catalysis because it presents an unprecedented opportunity to implement this very efficient enzyme into sustainable systems. We employed various EPR and FTIR spectroscopic methods, electrochemistry, bioinformatics, and theoretical modeling to investigate this unique enzymatic system. The presented work provides crucial details necessary to understand the mechanism of O₂ tolerance and uncover the structural basis for this desirable phenotype. Our sequence similarity analysis also suggests that this enzyme represents a large group of yet-to-be-characterized [FeFe] hydrogenases, setting an exciting avenue for future studies of these enzymes. Furthermore, we illustrate the plausibility of engineering the O₂-tolerant [FeFe] hydrogenases for efficient coupling to cyanobacterial photosystem I. Results obtained in this work establish the basis for future photosynthetic H₂ production strategies.