Ruhr University Bochum researchers identify proton transport mechanism in hydrogenase enzymes

Researchers from the Photobiotechnology group at Ruhr University Bochum have discovered the mechanism that allows [FeFe]-hydrogenase enzymes to capture and transport protons with extreme efficiency. These microbial enzymes can capture nearly 10,000 protons per second to produce hydrogen (H2) by combining electrons with protons.

The study, published in the Journal of the American Chemical Society, utilized zinc as an inhibitor to understand the biocatalyst's function. While zinc binds to various sites on the enzyme, the researchers found that inhibition only occurs when zinc binds to one specific location near the known proton transport pathway. This interaction blocks two histidine residues on the surface of the [FeFe]-hydrogenases, which act as a molecular pendulum driving the proton capture process.