6GL6

apo [FeFe]-hydrogenase HydA1 from Chlamydomonas reinhardtii, variant C377H

Summary for 6GL6

• Entry DOI: 10.2210/pdb6gl6/pdb
• Related: 3LX4
• Descriptor: Fe-hydrogenase, IRON/SULFUR CLUSTER, CHLORIDE ION, ... (6 entities in total)
• Functional Keywords: [fefe]-hydrogenase, iron sulfur cluster binding, oxidoreductase
• Biological source: Chlamydomonas reinhardtii (Chlamydomonas smithii)
• Total number of polymer chains: 1
• Total formula weight: 49425.86

Authors

Kertess, L.,Happe, T.,Hofmann, E. (deposition date: 2018-05-23, release date: 2018-12-26, Last modification date: 2024-05-15)

Primary citation

Rodriguez-Macia, P.,Kertess, L.,Burnik, J.,Birrell, J.A.,Hofmann, E.,Lubitz, W.,Happe, T.,Rudiger, O.
His-Ligation to the [4Fe-4S] Subcluster Tunes the Catalytic Bias of [FeFe] Hydrogenase.
J.Am.Chem.Soc., 141:472-481, 2019

PubMed Abstract: [FeFe] hydrogenases interconvert H into protons and electrons reversibly and efficiently. The active site H-cluster is composed of two sites: a unique [2Fe] subcluster ([2Fe]) covalently linked via cysteine to a canonical [4Fe-4S] cluster ([4Fe-4S]). Both sites are redox active and electron transfer is proton-coupled, such that the potential of the H-cluster lies very close to the H thermodynamic potential, which confers the enzyme with the ability to operate quickly in both directions without energy losses. Here, one of the cysteines coordinating [4Fe-4S] (Cys362) in the [FeFe] hydrogenase from the green algae Chlamydomonas reinhardtii ( CrHydA1) was exchanged with histidine and the resulting C362H variant was shown to contain a [4Fe-4S] cluster with a more positive redox potential than the wild-type. The change in the [4Fe-4S] cluster potential resulted in a shift of the catalytic bias, diminishing the H production activity but giving significantly higher H oxidation activity, albeit with a 200 mV overpotential requirement. These results highlight the importance of the [4Fe-4S] cluster as an electron injection site, modulating the redox potential and the catalytic properties of the H-cluster.

PubMed: 30545220
DOI: 10.1021/jacs.8b11149

Experimental method

X-RAY DIFFRACTION (1.8 Å)