The ATPase activity of purified mitochondrial ATPase (F1) of rat liver is inhibited less than 15% by sulfhydryl reagents when assayed in TrisCl buffer. In Trisbicarbonate buffer the ATPase activity of the enzyme is two- to three-fold higher than in TrisCl. Significantly, the ATPase activity stimulated by bicarbonate can be inhibited by mercurial agents such as p-chloromercuribenzoate. The number of sulfhydryl groups accessible to 14C-p-chloromercuribenzoate is the same in TrisCl and Trisbicarbonate buffers. These experiments suggest that mercurials most likely inhibit bicarbonate-stimulated ATPase activity by blocking a site associated with bicarbonate binding rather than by blocking distinct sulfhydryl-sensitive hydrolytic sites induced by bicarbonate.
|Original language||English (US)|
|Number of pages||7|
|Journal||Biochemical and Biophysical Research Communications|
|State||Published - Aug 23 1976|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology