Kinetics and thermodynamics of gas diffusion in a NiFe hydrogenase

Proteins. 2012 Mar;80(3):677-82. doi: 10.1002/prot.23248. Epub 2011 Dec 21.

Abstract

We have investigated O₂ and H₂ transport across a NiFe hydrogenase at the atomic scale by means of computational methods. The Wild Type protein has been compared with the V74Q mutant. Two distinct methodologies have been applied to study the gas access to the active site. Temperature locally enhanced sampling simulations have emphasized the importance of protein dynamics on gas diffusion. The O₂ diffusion free energy profiles, obtained by umbrella sampling, are in agreement with the known kinetic data and show that in the V74Q mutant, the inhibition process is lowered from both a kinetic and a thermodynamic point of view.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Catalytic Domain
  • Desulfovibrio / chemistry
  • Desulfovibrio / enzymology*
  • Desulfovibrio / genetics
  • Diffusion
  • Hydrogen / chemistry
  • Hydrogen / metabolism*
  • Hydrogenase / chemistry
  • Hydrogenase / genetics
  • Hydrogenase / metabolism*
  • Kinetics
  • Models, Molecular
  • Oxygen / chemistry
  • Oxygen / metabolism*
  • Point Mutation
  • Thermodynamics

Substances

  • Hydrogen
  • nickel-iron hydrogenase
  • Hydrogenase
  • Oxygen