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Effect of denaturants on multisite and unisite ATP hydrolysis by bovine heart submitochondrial particles with and without inhibitor protein
- Source :
- Archives of biochemistry and biophysics. 439(1)
- Publication Year :
- 2005
-
Abstract
- The effect of guanidinium hydrochloride (GdnHCl) on multisite and unisite ATPase activity by F0F1 of submitochondrial particles from bovine hearts was studied. In particles without control by the inhibitor protein, 50 mM GdnHCl inhibited multisite hydrolysis by about 85%; full inhibition required around 500 mM. In the range of 500–650 mM, GdnHCl enhanced the rate of unisite catalysis by promoting product release; it also increased the rate of hydrolysis of ATP bound to the catalytic site without GdnHCl. GdnHCl diminished the affinity of the enzyme for aurovertin. The effects of GdnHCl were irreversible. The results suggest that disruption of intersubunit contacts in F0F1 abolishes multisite hydrolysis and stimulates of unisite hydrolysis. Particles under control by the inhibitor protein were insensitive to concentrations of GdnHCl that induce the aforementioned alterations of F0F1 free of inhibitor protein, indicating that the protein stabilizes the global structure of particulate F1.
- Subjects :
- Protein Denaturation
Hydrochloride
Submitochondrial Particles
Biophysics
Biochemistry
Mitochondria, Heart
Catalysis
Hydrolysis
chemistry.chemical_compound
Adenosine Triphosphate
ATP hydrolysis
Atpase activity
Animals
Submitochondrial particle
Molecular Biology
Guanidine
chemistry.chemical_classification
Uncoupling Agents
Proteins
Inhibitor protein
Aurovertins
Enzyme Activation
Proton-Translocating ATPases
Enzyme
chemistry
Cattle
Subjects
Details
- ISSN :
- 00039861
- Volume :
- 439
- Issue :
- 1
- Database :
- OpenAIRE
- Journal :
- Archives of biochemistry and biophysics
- Accession number :
- edsair.doi.dedup.....a60906d942a5f4612aaf56db75aeb4bc