Influence of ADP, AMP‐PNP and of depletion of nucleotides on the structural properties of F1ATPase: a Fourier transform infrared spectroscopic study

FEBS Letters

Di Pancrazio, Francesca¹  Lippe, Giovanna¹  Dabbeni-Sala, Federica²  Bertoli, Enrico³  Tanfani, Fabio³ 

[1] Dipartimento di Scienze e Tecnologie Biomediche, Università di Udine, Via Gervasutta 48, Udine, Italy;Dipartimento di Farmacologia, Università di Padova, Largo Meneghetti, Padova, Italy;Istituto di Biochimica, Facoltà di Medicina e Chirurgia, Università di Ancona, Via Ranieri, 60131 Ancona, Italy

关键词: F1ATPase;    ATP synthase;    Infrared spectroscopy;    Protein structure;    FT-IR;    Fourier transform infrared;    Amide I′;    amide I band in a 2H2O medium;    AMP-PNP;    β;    γ-imidoadenosine 5′-triphosphate;    ADP/F1;    F1ATPase in the presence of ADP;    AMP-PNP/F1;    F1ATPase in the presence of AMP-PNP;    sol/F1;    soluble part of F1ATPase washed with a buffer in the absence of nucleotides;    insol/F1;    insoluble part of F1ATPase washed with a buffer in the absence of nucleotides;    TMPD;    temperature of maximum protein denaturation;   

DOI  :  10.1016/0014-5793(95)01022-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Mitochondrial F₁ATPase from beef heart was treated with different buffers in order to modulate the nucleotide content of the enzyme and then analysed by FT-IR spectroscopy. Treatment of F₁ATPase with a buffer lacking nucleotides and glycerol led to the formation of two fractions consisting of an inactive aggregated enzyme deprived almost completely of bound nucleotides and of an active enzyme containing ATP only in the tight sites and having a structure largely accessible to the solvent and a low thermal stability. Treatment of F₁ATPase with saturating ADP, which induced the hysteretic inhibition during turnover, or AMP-PNP did not affect remarkably the secondary structure of the enzyme complex but significantly increased its compactness and thermal stability. It was hypothesised that the formation of the inactive aggregated enzyme was mainly due to the destabilisation of the α-subunits of F₁ATPase and that the induction of the hysteretic inhibition is related to a particular conformation of the enzyme, which during turnover becomes unable to sustain catalysis.

【 授权许可】

Unknown