Conformational dynamics monitored by His‐179 and His‐200 of isolated thermophilic F1‐ATPase β subunit which reside at the entrance of the ‘conical tunnel’ in holoenzyme

FEBS Letters

Akutsu, Hideo²  Tozawa, Kaeko²  Yagi, Hiromasa²  Sekino, Nobuaki²  Soga, Masanobu²  Yoshida, Masasuke¹ 

[1] Research Laboratory of Resources Utilization, R-1, Tokyo Institute of Technology, Nagatsuta 4259, Midori-ku, Yokohama 226, Japan;Department of Bioengineering, Faculty of Engineering, Yokohama National University, 156 Tokiwadai, Hodogaya-ku, Tokohama 240, Japan

关键词: F1-ATPase;    Histidine residue;    1H NMR;    Ligand interaction;    Site-directed mutagenesis;    Thermophilic Bacillus;    TF1;    F1-ATPase from thermophilic Bacillus strain PS-3;    CF1;    and spinach chloroplasts;    respectively;    AMP-PNP;    5′adenylylinidodiphosphate;    HPLC;    high-performance liquid chromatography;   

DOI  :  10.1016/0014-5793(95)01276-2

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

When monitored by ¹H NMR at various pH values, most of the C-2 proton signals from 12 His residues of the isolated β subunit of thermophilic F₁-ATPase (TF₁) could be separately observed. Two of them were assigned to His-179 and His-200 which reside at the entrance of a ‘conial tunnel’ to reach catalytic site in the crystal structure of F₁-ATPase. His-200 gave doublet, suggesting that this region is not a rigid α-helix in the isolated β subunit. The binding of Mg · AMP-PNP changed the chemical shifts of His-179 and His-200 significantly. Although His-119 located at the opposite side of the conical tunnel was not affected by the nucleotide-binding, it contributed to the stability of β subunit and the efficiency of the catalysis of the holoenzyme.

【 授权许可】

Unknown