8BTS

Nitrogenase MoFe protein from A. vinelandii alpha double mutant C45A/L158C

8BTS の概要

• エントリーDOI: 10.2210/pdb8bts/pdb
• 分子名称: Nitrogenase protein alpha chain, Nitrogenase molybdenum-iron protein beta chain, 3-HYDROXY-3-CARBOXY-ADIPIC ACID, ... (8 entities in total)
• 機能のキーワード: n2-fixation, nitrogenase, cooperativity, ammonia, hydrogen, metalloenzyme, femo-cofactor, p cluster, o2-sensitivity, oxidoreductase
• 由来する生物種: Azotobacter vinelandii DJ; 詳細
• タンパク質・核酸の鎖数: 8
• 化学式量合計: 472792.53

構造登録者

Wagner, T.,Maslac, N. (登録日: 2022-11-29, 公開日: 2023-06-07, 最終更新日: 2024-06-19)

主引用文献

Cadoux, C.,Ratcliff, D.,Maslac, N.,Gu, W.,Tsakoumagkos, I.,Hoogendoorn, S.,Wagner, T.,Milton, R.D.
Nitrogen Fixation and Hydrogen Evolution by Sterically Encumbered Mo-Nitrogenase.
Jacs Au, 3:1521-1533, 2023

PubMed Abstract: The substrate-reducing proteins of all nitrogenases (MoFe, VFe, and FeFe) are organized as αß(γ) multimers with two functional halves. While their dimeric organization could afford improved structural stability of nitrogenases , previous research has proposed both negative and positive cooperativity contributions with respect to enzymatic activity. Here, a 1.4 kDa peptide was covalently introduced in the proximity of the P cluster, corresponding to the Fe protein docking position. The Strep-tag carried by the added peptide simultaneously sterically inhibits electron delivery to the MoFe protein and allows the isolation of partially inhibited MoFe proteins (where the half-inhibited MoFe protein was targeted). We confirm that the partially functional MoFe protein retains its ability to reduce N to NH, with no significant difference in selectivity over obligatory/parasitic H formation. Our experiment concludes that wild-type nitrogenase exhibits negative cooperativity during the steady state regarding H and NH formation (under Ar or N), with one-half of the MoFe protein inhibiting turnover in the second half. This emphasizes the presence and importance of long-range (>95 Å) protein-protein communication in biological N fixation in .

PubMed: 37234119
DOI: 10.1021/jacsau.3c00165

実験手法

X-RAY DIFFRACTION (3.03 Å)