1.
FEBS Lett
; 582(30): 4158-62, 2008 Dec 24.
Artigo
em Inglês
| MEDLINE
| ID: mdl-19041645
RESUMO
In the presence of the uncoupler, external zinc ions inhibit rapidly turnover of cytochrome c oxidase reconstituted in phospholipid vesicles or bound to the membrane of intact mitochondria. The effect is promoted by electron leaks into the oxidase during preincubation with Zn(2+). Inhibition of liposome-bound bovine cytochrome oxidase by external Zn(2+) titrates with a K(i) of 1+/-0.3 microM. Presumably, the Zn(2+)-binding group at the positively charged side is not reactive in the oxidized enzyme, but becomes accessible to the cation in some partially reduced state(s) of the oxidase; reduction of Cu(B) is tentatively proposed to be responsible for the effect.