Biochemistry

How does nitrogenase spring its trap?

See allHide authors and affiliations

Science  06 Oct 2017:
Vol. 358, Issue 6359, pp. 77-78
DOI: 10.1126/science.358.6359.77-d

It's a bit of a chemical mystery why, after eons of evolution to optimize efficiency, nitrogenase enzymes still make hydrogen as a by-product when they make ammonia. Recent work suggests that this step is key to binding the nitrogen molecule in the active site. Khadka et al. attached the molybdenum-iron protein of nitrogenase to an electrode to isolate the kinetics of hydrogen production. By measuring deuterium isotope effects and performing accompanying density functional theory calculations, they established that the rate-limiting step involves formation of one hydrogen molecule by proton transfer from sulfur to a bridging iron hydride.

J. Am. Chem. Soc. 10.1021/jacs.7b07311 (2017).

Navigate This Article