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Docking and migration of carbon monoxide in nitrogenase: the case for gated pockets from infrared spectroscopy and molecular dynamics.

ABSTRACT: 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.

SUBMITTER: Gee LB

PROVIDER: S-EPMC4522414 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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Docking and migration of carbon monoxide in nitrogenase: the case for gated pockets from infrared spectroscopy and molecular dynamics.

Gee Leland B LB Leontyev Igor I Stuchebrukhov Alexei A Scott Aubrey D AD Pelmenschikov Vladimir V Cramer Stephen P SP

Biochemistry 20150515 21

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 me ...[more]

PMID: 25919807

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