Journal
BIOCHIMIE
Volume 180, Issue -, Pages 222-228Publisher
ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER
DOI: 10.1016/j.biochi.2020.11.012
Keywords
F1FO-ATPase; Mitochondria; Midgut gland; Mytilus galloprovincialis; Permeability transition pore; Sulfide
Categories
Funding
- University of Bologna, Italy
Ask authors/readers for more resources
The study found that the F1FO-ATPase activity in mussel midgut gland mitochondria is insensitive to NaHS, which may help mussels cope with environmental sulfide.
The molecular mechanisms which rule the formation and opening of the mitochondrial permeability transition pore (mPTP), the lethal mechanism which permeabilizes mitochondria to water and solutes and drives the cell to death, are still unclear and particularly little investigated in invertebrates. Since Ca2+ increase in mitochondria is accompanied by mPTP opening and the participation of the mitochondrial FiFo-ATPase in the mPTP is increasingly sustained, the substitution of the natural cofactor Mg2+ by Ca2+ in the F1FO-ATPase activation has been involved in the mPTP mechanism. In mussel midgut gland mitochondria the similar kinetic properties of the Mg2+ - or Ca2+-dependent F1FO-ATPase activities, namely the same affinity for ATP and bi-site activation kinetics by the ATP substrate, in spite of the higher enzyme activity and coupling efficiency of the Mg2+-dependent F1FO-ATPase, suggest that both enzyme activities are involved in the bioenergetic machinery. Other than being a mitochondrial poison and environmental contaminant, sulfide at low concentrations acts as gaseous mediator and can induce post-translational modifications of proteins. The sulfide donor NaHS, at micromolar concentrations, does not alter the two F1FO-ATPase activities, but desensitizes the mPTP to Ca2+ input. Unexpectedly, NaHS, under the conditions tested, points out a chemical refractoriness of both F1FO-ATPase activities and a failed relationship between the Ca2+-dependent F1FO-ATPase and the mPTP in mussels. The findings suggest that mPTP role and regulation may be different in different taxa and that the F1FO-ATPase insensitivity to NaHS may allow mussels to cope with environmental sulfide. (C) 2020 Elsevier B.V. and Societe Francaise de Biochimie et Biologie Moleculaire (SFBBM). All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available