5A4F

The mechanism of Hydrogen Activation by NiFe-hydrogenases.

5A4F の概要

• エントリーDOI: 10.2210/pdb5a4f/pdb
• 関連するPDBエントリー: 5A4I 5A4M
• 分子名称: Hydrogenase-1 large chain, CHLORIDE ION, Hydrogenase-1 small chain, ... (11 entities in total)
• 機能のキーワード: oxidoreductase, nife-hydrogenase, hydrogen lysis, redox, fes cluster, catalysis
• 由来する生物種: Escherichia coli str. K-12 substr. MC4100; 詳細
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 205781.84

構造登録者

Evans, R.M.,Brooke, E.J.,Wehlin, S.A.M.,Nomerotskaia, E.,Sargent, F.,Carr, S.B.,Phillips, S.E.V.,Armstrong, F.A. (登録日: 2015-06-09, 公開日: 2015-11-25, 最終更新日: 2024-11-06)

主引用文献

Evans, R.M.,Brooke, E.J.,Wehlin, S.A.,Nomerotskaia, E.,Sargent, F.,Carr, S.B.,Phillips, S.E.,Armstrong, F.A.
Mechanism of hydrogen activation by [NiFe] hydrogenases.
Nat. Chem. Biol., 12:46-50, 2016

PubMed Abstract: The active site of [NiFe] hydrogenases contains a strictly conserved arginine that suspends a guanidine nitrogen atom <4.5 Å above the nickel and iron atoms. The guanidine headgroup interacts with the side chains of two conserved aspartic acid residues to complete an outer-shell canopy that has thus far proved intractable to investigation by site-directed mutagenesis. Using hydrogenase-1 from Escherichia coli, the strictly conserved residues R509 and D574 have been replaced by lysine (R509K) and asparagine (D574N) and the highly conserved D118 has been replaced by alanine (D118A) or asparagine (D118N/D574N). Each enzyme variant is stable, and their [(RS)2Niμ(SR)2Fe(CO)(CN)2] inner coordination shells are virtually unchanged. The R509K variant had >100-fold lower activity than native enzyme. Conversely, the variants D574N, D118A and D118N/D574N, in which the position of the guanidine headgroup is retained, showed 83%, 26% and 20% activity, respectively. The special kinetic requirement for R509 implicates the suspended guanidine group as the general base in H2 activation by [NiFe] hydrogenases.

PubMed: 26619250
DOI: 10.1038/nchembio.1976

実験手法

X-RAY DIFFRACTION (1.25 Å)