6E6Q

1.20 A resolution structure of the C-terminally truncated [2Fe-2S] ferredoxin (Bfd) from Pseudomonas aeruginosa

6E6Q の概要

• エントリーDOI: 10.2210/pdb6e6q/pdb
• 分子名称: Bacterioferritin-associated ferredoxin, FE2/S2 (INORGANIC) CLUSTER (3 entities in total)
• 機能のキーワード: iron mobilization, [2fe-2s] ferredoxin, bfd, anion binding site, electron transport
• 由来する生物種: Pseudomonas aeruginosa
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 12689.71

構造登録者

Lovell, S.,Wijerathne, H.,Battaile, K.P.,Yao, H.,Wang, Y.,Rivera, M. (登録日: 2018-07-25, 公開日: 2018-09-19, 最終更新日: 2023-10-11)

主引用文献

Wijerathne, H.,Yao, H.,Wang, Y.,Lovell, S.,Battaile, K.P.,Rivera, M.
Bfd, a New Class of [2Fe-2S] Protein That Functions in Bacterial Iron Homeostasis, Requires a Structural Anion Binding Site.
Biochemistry, 57:5533-5543, 2018

PubMed Abstract: Mobilization of iron from bacterioferritin (BfrB) requires specific interactions with a [2Fe-2S] ferredoxin (Bfd). Blocking the BfrB:Bfd interaction results in irreversible iron accumulation in BfrB and iron deficiency in the cytosol [Eshelman, K., et al. (2017) Metallomics 9, 646-659]. The only known Bfd structure, which was obtained in complex with BfrB (Protein Data Bank entry 4E6K ), indicated a new fold and suggested that the stability of Bfd is aided by an anion binding site consisting of R26, R29, and K46. We investigated the Bfd fold using site-directed mutagenesis, X-ray crystallography, and biochemistry in solution. The X-ray structure, which is nearly identical to that of Bfd in the BfrB:Bfd complex, shows that the [2Fe-2S] cluster preorganizes residues at the BfrB:Bfd interface into a structure complementary to the Bfd binding site on BfrB. Studies in solution showed rapid loss of the [2Fe-2S] cluster at a low ionic strength but higher stability with an increasing ionic strength, thus supporting a structural anion binding site. Structures of the R26E and R26E/K46Y mutants are nearly identical to that of Bfd, except for a new network of hydrogen bonds stabilizing the region encompassing the former anion binding site. The stability of the R26E and R26E/K46Y mutants, which is weakly and completely independent of solution ionic strength, respectively, corroborates that Bfd requires an anion binding site. The mutations, which caused only small changes to the strength of the BfrB:Bfd interaction and mobilization of iron from BfrB, indicate that the anion binding site in Bfd serves primarily a structural role.

PubMed: 30183257
DOI: 10.1021/acs.biochem.8b00823

実験手法

X-RAY DIFFRACTION (1.2 Å)