Structural highlights
6gm6 is a 1 chain structure with sequence from Chlre. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
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Ligands: | , , |
Related: | 3lx4, 4r0v |
Gene: | hyd1, HYD1, hydA, hydA1, CHLRE_03g199800v5, CHLREDRAFT_183963 (CHLRE) |
Activity: | Ferredoxin hydrogenase, with EC number 1.12.7.2 |
Resources: | FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT |
Publication Abstract from PubMed
The unmatched catalytic turnover rates of [FeFe]-hydrogenases require an exceptionally efficient proton-transfer (PT) pathway to shuttle protons as substrates or products between bulk water and catalytic center. For clostridial [FeFe]-hydrogenase CpI such a pathway has been proposed and analyzed, but mainly on a theoretical basis. Here, eleven enzyme variants of two different [FeFe]-hydrogenases (CpI and HydA1) with substitutions in the presumptive PT-pathway are examined kinetically, spectroscopically, and crystallographically to provide solid experimental proof for its role in hydrogen-turnover. Targeting key residues of the PT-pathway by site directed mutagenesis significantly alters the pH-activity profile of these variants and in presence of H2 their cofactor is trapped in an intermediate state indicative of precluded proton-transfer. Furthermore, crystal structures coherently explain the individual levels of residual activity, demonstrating e.g. how trapped H2O molecules rescue the interrupted PT-pathway. These features provide conclusive evidence that the targeted positions are indeed vital for catalytic proton-transfer.
Crystallographic and spectroscopic assignment of the proton transfer pathway in [FeFe]-hydrogenases.,Duan J, Senger M, Esselborn J, Engelbrecht V, Wittkamp F, Apfel UP, Hofmann E, Stripp ST, Happe T, Winkler M Nat Commun. 2018 Nov 9;9(1):4726. doi: 10.1038/s41467-018-07140-x. PMID:30413719[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Duan J, Senger M, Esselborn J, Engelbrecht V, Wittkamp F, Apfel UP, Hofmann E, Stripp ST, Happe T, Winkler M. Crystallographic and spectroscopic assignment of the proton transfer pathway in [FeFe]-hydrogenases. Nat Commun. 2018 Nov 9;9(1):4726. doi: 10.1038/s41467-018-07140-x. PMID:30413719 doi:http://dx.doi.org/10.1038/s41467-018-07140-x