Activation of a complex of ATPase with the natural protein inhibitor in submitochondrial particles

Khodjaev, E.Yu.; Komarnitsky, F.B.; Capozza, Giuseppe; Dukhovich, V.F.; Chernyak, Boris V.; Papa, Sergio

doi:10.1016/0014-5793(90)80469-y

Cited by 12 publications

(12 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The reactivation was slower at lower pH (curves 3A, 3B and 5B) and was completely prevented by MgATP (curve 4A). The reactivation of IF,-ATPase complex in submitochondrial particles from beef heart possesses the same features [13]. These data indicate that the inactivation of ATPase which is induced by uncoupler or rotenone and persisted after disruption of the cells is completely the result of inhibitor protein's action.…”

Section: Reactivation Of Mitochondrial Atpasesupporting

confidence: 54%

Mitochondrial ATP hydrolysis and ATP depletion in thymocytes and Ehrlich ascites carcinoma cells

Chernyak

Gabai

1994

FEBS Letters

Self Cite

View full text Add to dashboard Cite

When Ehrlich ascites carcinoma (EAC) cells and thymocytes were treated with uncoupler or rotenone in glucose-free medium, rapid ATP depletion was observed in both types of the cells. Oligomycin slowed down ATP loss in thymocytes, but not in EAC cells. Thus, mitochondrial ATP hydrolysis appears to be significant in deenergized thymocytes in contrast to EAC cells, in which other ATP consuming reactions were prevailing. Complete deenergization of mitochondria by uncoupler or rotenone in these cells resulted in inactivation of mitochondrial ATPase by 65-75%. The effect was observed after complete and rapid (20-30 s) disruption of the cells with detergent, Lubrol WX. ATPase was blocked by the specific inhibitor protein (IF,) as it was shown by the studies on reactivation of this enzyme. When respiration is blocked but ATP content is supported by glycolysis, mitochondrial ATPase is not suppressed by IF,, and maintains the energization of mitochondria. It is concluded that under complete de-energization of mitochondria IF, significantly inhibits mitochondrial ATP hydrolysis and may slow down ATP loss in thymocytes and EAC cells.

show abstract

Section: Reactivation Of Mitochondrial Atpasesupporting

confidence: 54%

Mitochondrial ATP hydrolysis and ATP depletion in thymocytes and Ehrlich ascites carcinoma cells

Chernyak

Gabai

1994

FEBS Letters

Self Cite

View full text Add to dashboard Cite

show abstract

“…Zn" at 40 PM caused release of Ca'+ from mitochondria [14] possibly by inhibition of respiration rather than a direct effect on a Ca"-transporter, and Zn2' at > 12.5 ,uM reversed inhibition of the F, ATPase of sub-mitochondrial particles by the natural inhibitor protein [15].…”

Section: Hepes Tes Rotenonementioning

confidence: 94%

The pH‐dependent anion‐conducting channel of the mitochondrial inner membrane is potently inhibited by zinc ions

Selwyn

Choo

1993

FEBS Letters

View full text Add to dashboard Cite

Zinc is a potent reversible inlubitor of the pH-dependent anion-conductmg channel m the mitochondrial inner membrane, 50% inhibition was produced by 1.5 PM added Zn" at which point free Zn" was 5 10~8 M. Inhibition by Zn" IS rapid but can be prevented or rapidly reversed by excess EDTA. Concentrations of Zn" higher than 4 PM caused reversal of inhibition to a variable extent depending on the anion. Under these conditions Zn*' did not inhibit ribose entry, the phosphate transporter, or the pH-Insensitive component of the NO,-uniport.

show abstract

“…pH is thought to affect the number of active enzyme molecules, in relation to the dissociation of the inhibitory peptide IF1, and not the catalytic turnover (Norling et al, 1990;Khodjaev et al, 1990;Chernyak et al, 1987). We have investigated whether a similar pH-dependency could be observed in mitochondria from plants.…”

Section: Ph Effect On the Rate Of Atp Hydrolysismentioning

confidence: 98%

“…It has been reported that alkaline pH favours ATP hydrolysis by F,-ATPase, in solution (Glaser et al, 1989;Norling et al, 1990) or bound to submitochondrial particles (Khodjaev et al, 1990). pH is thought to affect the number of active enzyme molecules, in relation to the dissociation of the inhibitory peptide IF1, and not the catalytic turnover (Norling et al, 1990;Khodjaev et al, 1990;Chernyak et al, 1987).…”

Section: Ph Effect On the Rate Of Atp Hydrolysismentioning

confidence: 99%

“…A partial inactivation of the ATPase was observed at pH < 8 in deenergized rat liver mitochondria (Chernyak et al, 1987). Similarly, alkaline pH favours the activation of the ATPase in inside-out vesicles from beef heart, even under deenergized conditions (Khodjaev et al, 1990). An inhibitory effect of low pH in the presence of IF1 was also observed in F, isolated from potato tuber mitochondria (Norling et al, 1990).…”

mentioning

confidence: 93%

See 1 more Smart Citation

Deactivation of F₀F₁ ATPase in intact plant mitochondria

Valerio¹,

Diolez²,

Haraux³

1994

European Journal of Biochemistry

View full text Add to dashboard Cite

By using a method especially adapted to intact (pea leaf) mitochondria, we studied the regulation of the F,F, ATPase by the electrochemical proton gradient (ApHt) and by the matricial pH. The kinetics of decay of the ATP hydrolase activity was studied immediately after the collapse of the electrochemical proton gradient by an uncoupler. At pH 7.5, three inhibitors of the ATPase (venturicidin, tri-n-butyl tin and aurovertin), used at non-saturating concentrations, inhibited ATP hydrolysis to the same extent throughout the decay. This showed that the activity was totally controlled by the ATPase during all the decay and rules out any involvement of the phosphate or nucleotide carriers. This interpretation was confirmed by the fact that carboxyatractyloside, an inhibitor of the ATP/ADP antiporter, had a strong effect only on the initial rate of ATP hydrolysis, but not on the rate measured after some tens of seconds of decay. Oligomycin, at variance with the other ATPase inhibitors, interfered with the deactivation process, suggesting that its effect depends on the conformational state of the enzyme. Between pH 6.5 and 7.5, the hydrolase activity rose continuously and was still kinetically controlled by the ATPase. At higher pH value, the activity slightly decreased and appeared limited by at least one of the carriers. The activity of the ATPase itself, free of any transport process, seemed to increase monotonously with pH from 6.5 to 8.The electrochemical proton gradient is required to maintain the ATPase active, whereas no effect can be observed on transport processes. Matricial pH, while modulating the apparent catalytic turnover, has no marked effect on the rate of deactivation. These results, obtained with intact mitochondria, extend previous observations on the isolated enzyme and question the binding of IF1 as a rate-limiting step for ATPase deactivation.

show abstract

Activation of a complex of ATPase with the natural protein inhibitor in submitochondrial particles

Cited by 12 publications

References 14 publications

Mitochondrial ATP hydrolysis and ATP depletion in thymocytes and Ehrlich ascites carcinoma cells

Mitochondrial ATP hydrolysis and ATP depletion in thymocytes and Ehrlich ascites carcinoma cells

The pH‐dependent anion‐conducting channel of the mitochondrial inner membrane is potently inhibited by zinc ions

Deactivation of F₀F₁ ATPase in intact plant mitochondria

Contact Info

Product

Resources

About

Activation of a complex of ATPase with the natural protein inhibitor in submitochondrial particles

Cited by 12 publications

References 14 publications

Mitochondrial ATP hydrolysis and ATP depletion in thymocytes and Ehrlich ascites carcinoma cells

Mitochondrial ATP hydrolysis and ATP depletion in thymocytes and Ehrlich ascites carcinoma cells

The pH‐dependent anion‐conducting channel of the mitochondrial inner membrane is potently inhibited by zinc ions

Deactivation of F0F1 ATPase in intact plant mitochondria

Contact Info

Product

Resources

About

Deactivation of F₀F₁ ATPase in intact plant mitochondria