Work

Aerobic Damage to [FeFe]‐Hydrogenases: Activation Barriers for the Chemical Attachment of O2

Year: 2014

Type: article

Abstract: [FeFe]‐hydrogenases are the best natural hydrogen‐producing enzymes but their biotechnological exploitation is hampered by their extreme oxygen sensitivity. The free energy profile for the chemical attachment of O2 to the enzyme active site was investigated by using a range‐separated density functional re‐parametrized to reproduce high‐level ab initio data. An activation free‐energy barrier of 13 kcal mol−1 was obtained for chemical bond formation between the di‐iron active site and O2, a value in good agreement with experimental inactivation rates. The oxygen binding can be viewed as an inner‐sphere electron‐transfer process that is strongly influenced by Coulombic interactions with the proximal cubane cluster and the protein environment. The implications of these results for future mutation studies with the aim of increasing the oxygen tolerance of this enzyme are discussed.

Source: Angewandte Chemie

DOI: 10.1002/ange.201400534

Authors: Adam Kubas, David De Sancho, Robert B. Best, Jochen Blumberger

Institutions: University College London, University of Cambridge, National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases

Language: English

Topic: Metalloenzymes and iron-sulfur proteins

Subfield: Renewable Energy, Sustainability and the Environment

Field: Energy

Domain: Physical Sciences

Open Access status: bronze

Funders: National Institutes of Health, Engineering and Physical Sciences Research Council, National Institute of Diabetes and Digestive and Kidney Diseases