Ca2+ as cofactor of the mitochondrial H+ -translocating F1 FO -ATP(hydrol)ase.
Proteins
; 89(5): 477-482, 2021 05.
Article
em En
| MEDLINE
| ID: mdl-33378096
ABSTRACT
The mitochondrial F1 FO -ATPase in the presence of the natural cofactor Mg2+ acts as the enzyme of life by synthesizing ATP, but it can also hydrolyze ATP to pump H+ . Interestingly, Mg2+ can be replaced by Ca2+ , but only to sustain ATP hydrolysis and not ATP synthesis. When Ca2+ inserts in F1 , the torque generation built by the chemomechanical coupling between F1 and the rotating central stalk was reported as unable to drive the transmembrane H+ flux within FO . However, the failed H+ translocation is not consistent with the oligomycin-sensitivity of the Ca2+ -dependent F1 FO -ATP(hydrol)ase. New enzyme roles in mitochondrial energy transduction are suggested by recent advances. Accordingly, the structural F1 FO -ATPase distortion driven by ATP hydrolysis sustained by Ca2+ is consistent with the permeability transition pore signal propagation pathway. The Ca2+ -activated F1 FO -ATPase, by forming the pore, may contribute to dissipate the transmembrane H+ gradient created by the same enzyme complex.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Trifosfato de Adenosina
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Cálcio
/
Coenzimas
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ATPases Mitocondriais Próton-Translocadoras
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Magnésio
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Mitocôndrias Cardíacas
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Proteins
Assunto da revista:
BIOQUIMICA
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Itália