Docking and Migration of Carbon Monoxide in Nitrogenase: The Case for Gated Pockets from Infrared Spectroscopy and Molecular Dynamics
journal contributionposted on 02.06.2015, 00:00 by Leland B. Gee, Igor Leontyev, Alexei Stuchebrukhov, Aubrey D. Scott, Vladimir Pelmenschikov, Stephen P. Cramer
Evidence of a CO docking site near the FeMo cofactor in nitrogenase has been obtained by Fourier transform infrared spectroscopy-monitored low-temperature photolysis. We investigated the possible migration paths for CO from this docking site using molecular dynamics calculations. The simulations support the notion of a gas channel with multiple internal pockets from the active site to the protein exterior. Travel between pockets is gated by the motion of protein residues. Implications for the mechanism of nitrogenase reactions with CO and N2 are discussed.