ATP synthesis catalyzed by the mitochondrial F<sub>1</sub>‐F<sub>0</sub> ATP synthase is not a reversal of its ATPase activity

Сыроешкин, А. В.; Vasilyeva, Е. А.; Vinogradov, Andrei D.

doi:10.1016/0014-5793(95)00487-t

Cited by 46 publications

(31 citation statements)

References 39 publications

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“…This state is caused by ADP, formed by hydrolysis of ATP, which cannot detach from the enzyme, but becomes entrapped in a nucleotide-binding site (27)(28)(29)(30)(31)(32). The decline of pauses corresponding to the ADP inhibited state in the presence of tentoxin strongly suggests that tentoxin is relieving ADP inhibition.…”

Section: Tentoxin Inhibition Of Individual F 1 -Atpase Molecules 9687mentioning

confidence: 97%

Complete Inhibition and Partial Re-activation of Single F1-ATPase Molecules by Tentoxin

Pavlova

Shimabukuro

Hisabori

et al. 2004

Journal of Biological Chemistry

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We found that inhibition by tentoxin caused a virtually complete stop of rotation, which was partially relieved at higher tentoxin concentrations. Re-activation, however, was not simply a reversal of inhibition; while the torque appears unaffected as compared with the situation without tentoxin, F 1 under re-activating conditions was less susceptible to inhibitory ADP binding but displayed a large number of short pauses, indicating infringed energy conversion.F 1 -ATPase, the water-soluble part of F o F 1 -ATP synthase, splits ATP into ADP and inorganic phosphate (1, 2). The enzyme is found ubiquitously in bacteria, mitochondria, and chloroplasts and consists of five different subunits with a stoichiometry of ␣ 3 ␤ 3 ␥␦⑀. Its ␣ 3 ␤ 3 ␥ subcomplex is the minimal assembly capable of continuous hydrolysis of ATP. The ␣ and ␤ subunits, arranged in an alternating manner like the elements of an orange, form a hexagon with the ␥ subunit in its center (3). Rotation of the ␥ subunit within the ␣ 3 ␤ 3 ␥ hexagon during

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Section: Tentoxin Inhibition Of Individual F 1 -Atpase Molecules 9687mentioning

confidence: 97%

Complete Inhibition and Partial Re-activation of Single F1-ATPase Molecules by Tentoxin

Pavlova

Shimabukuro

Hisabori

et al. 2004

Journal of Biological Chemistry

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“…The membrane-bound F 0 ⅐F 1 in tightly coupled P. denitrificans vesicles is ideally suited for studies on the reversibility of the ⌬ H ϩ-supported ATP synthesis. In some respects, F 0 ⅐F 1 synthase of P. denitrificans seemed to be remarkably similar to the mitochondrial ADP(Mg 2ϩ )-inhibited enzyme form stabilized by azide (22) or to the thermophilic Bacillus PS3 mutant F 0 ⅐F 1 , which is incapable of ATP binding to the "non-catalytic" sites on ␣-subunits (33). This similarity is corroborated by recent reports demonstrating that the ATPase activity of coupled vesicles derived from P. denitrificans is susceptible to activation by sulfite and/or by energization (34,35).…”

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confidence: 99%

“…Several phenomena such as hysteresis in onset of the catalytic activity (17), slow inhibition of ATPase by Mg 2ϩ (18), activation of ATP hydrolysis by sulfite and other anions (9,19,20), and the inhibitory effect of azide (9) can be consistently explained by the kinetic scheme in which the slowly reversible interconversion between catalytically competent enzyme-ADP intermediate and its inactive "isomer" plays the central role (5). Perhaps the most intriguing property of the ADP(Mg 2ϩ )-deactivated ATPase is that being inactive in ATP hydrolysis, it is fully competent in the ATP synthase activity (21,22).…”

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confidence: 99%

Energy-dependent Transformation of F0·F1-ATPase in Paracoccus denitrificans Plasma Membranes

Zharova

Vinogradov

2004

Journal of Biological Chemistry

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F 0 ⅐F 1 -ATPases (ATP synthases) are the oligomeric molecular machines that couple ATP hydrolysis (synthesis) with proton translocation across the energy-transducing membranes in mitochondria, chloroplasts, and bacteria. The structural arrangement of the subunits within F 0 ⅐F 1 complexes of various organisms is assumed to be very similar (1-3). The hydrophilic F 1 is composed of a trimer of tightly packed ␣⅐␤-subunit pairs and one copy each of the ␦-, ⑀-, and ␥-subunits (Escherichia coli nomenclature for the subunits is used). Long rod-like ␥-subunit is asymmetrically positioned in the central cavity of the almost spherical globular ␣⅐␤ trimer. F 0 component is the hydrophobic complex composed of 10 -14 transmembraneously positioned c-, one a-, and two b-subunits. The hydrophilic parts of b-subunits are bound to F 1 (to one pair of ␣⅐␤-and one ␦-subunit), thus forming the peripheral stalk. The other central stalk is formed by ␥⅐⑀ complex, which interacts with c-subunit(s) arranged in a ring. F 1 bears three "catalytic" nucleotide-binding sites located on ␤-subunits, and F 0 serves as a proton-conducting path. It is generally believed that the coupling between the ATP hydrolysis (synthesis) and flow of protons across the membrane results from the consequence of the long distance conformational change: ␣⅐␤-pair-associated chemical catalysis 3 ␥⅐⑀ 3 ab 2 c n leading to rotation of the rotor (␥⅐⑀ bound to c-ring) within the stator (␣⅐␤ trimer fixed by two b-and one ␦-subunits) (4).The kinetics of ATP hydrolysis catalyzed by the soluble F 1 or membrane-bound F 0 ⅐F 1 preparations of the enzyme (coupled or uncoupled) are very complex (5). It has been documented that the key factor for such a complexity is a formation of so-called ADP(Mg 2ϩ )-inhibited form of the enzyme originally described (6) and kinetically characterized in a number of reports published by our (7-11) and other groups (12-16). Several phenomena such as hysteresis in onset of the catalytic activity (17), slow inhibition of ATPase by Mg 2ϩ (18), activation of ATP hydrolysis by sulfite and other anions (9,19,20), and the inhibitory effect of azide (9) can be consistently explained by the kinetic scheme in which the slowly reversible interconversion between catalytically competent enzyme-ADP intermediate and its inactive "isomer" plays the central role (5). Perhaps the most intriguing property of the ADP(Mg 2ϩ )-deactivated ATPase is that being inactive in ATP hydrolysis, it is fully competent in the ATP synthase activity (21,22).The ADP(Mg 2ϩ )/ATP-and possibly ⌬ H ϩ 1 -induced rearrangement within F 0 ⅐F 1 complex that trigger its ATP hydrolase and ATP synthase activities remains unclear. The ⑀-subunit, an endogenous inhibitor of the ATP hydrolase activity of F 1 and F 0 ⅐F 1 (23, 24), seems to be the most likely candidate for the triggering function. It has been shown that two distinct domains of the ⑀-subunit can exist in different conformations interacting differently with ␥-subunit (25-27). Most recently, it has been reported that the isolated ⑀...

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“…Further investigations of the mechanism of ATPase regulation by Dl H þ and IF1 should now take into account this possible additional form of ATP synthase. This IF1-dependent conversion of active ATPase into latent ATPase resembles that induced by MgADP and Dl H þ in bovine heart SMP [32,34] and in Pseudomonas denitrificans [46]. Whether the presently described latent state of ATPase could synthesize ATP under appropriate conditions or not has not been established so far.…”

Section: Discussionmentioning

confidence: 99%

“…Interaction of F 0 F 1 -ATPase with adenine nucleotides is very complex in itself. In addition to simple competitive inhibition of ATP hydrolysis, ADP causes hysteretic inhibition of ATPase activity in contrast to nonadenylic nucleotides IDP and GDP [32][33][34][35][36][37]. Likewise, MgADP-inhibited enzyme can undergo an energy-dependent transformation changing its functional properties [32][33][34].…”

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confidence: 99%

Functional transitions of F₀F₁‐ATPase mediated by the inhibitory peptide IF1 in yeast coupled submitochondrial particles

Galkin¹,

Venard²,

Vaillier³

et al. 2004

European Journal of Biochemistry

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The mechanism of inhibition of yeast F 0 F 1 -ATPase by its naturally occurring protein inhibitor (IF1) was investigated in submitochondrial particles by studying the IF1-mediated ATPase inhibition in the presence and absence of a protonmotive force. In the presence of protonmotive force, IF1 added during net NTP hydrolysis almost completely inhibited NTPase activity. At moderate IF1 concentration, subsequent uncoupler addition unexpectedly caused a burst of NTP hydrolysis. We propose that the protonmotive force induces the conversion of IF1-inhibited F 0 F 1 -ATPase into a new form having a lower affinity for IF1. This form remains inactive for ATP hydrolysis after IF1 release. Uncoupling simultaneously releases ATP hydrolysis and converts the latent form of IF1-free F 0 F 1 -ATPase back to the active form. The relationship between the different steps of the catalytic cycle, the mechanism of inhibition by IF1 and the interconversion process is discussed.Keywords: ATP synthase; catalytic state; inhibitory peptide; latent ATPase; protonmotive force; yeast.Energy-driven ATP synthesis in energy-transducing membranes is carried out by membrane-bound F 0 F 1 -ATPase complex or ATP synthase [1]. The extrinsic F 1 subcomplex is composed of five types of subunits in the stoichiometry a 3 b 3 cde. Three fast-exchangeable nucleotide-binding sites, presumably catalytic, and three slow-exchangeable nucleotide-binding sites, certainly noncatalytic, reside in a/b interfaces [2,3] (an alternative point of view can be found in [4]). The membranous F 0 subcomplex promotes proton translocation, energetically coupled to ATP synthesis/ hydrolysis via a stalk connecting F 0 and F 1 . F 1 can be biochemically separated from F 0 and remains competent for uncoupled ATP hydrolysis. Numerous data, including direct observations of the rotation of the central axis of F 0 F 1 relative to a 3 b 3 crown during ATP hydrolysis [5,6], indicate that F 0 F 1 is a rotary motor, with an asymmetrical rotor composed, in mitochondria, of c, d and e subunits, anchored to a membranous decameric ring of c subunits thought to compose a proton-driven turbine [7].Mitochondrial F 0 F 1 is regulated by a naturally occurring inhibitor protein called IF1 [8]. IF1 is a small acid-and heat-stable protein, which stoichiometrically binds to the F 1 sector of ATP synthase and inhibits ATP hydrolysis [8][9][10][11][12][13][14][15][16][17][18][19]. Dl H þ is believed to favour the release of IF1 from ATP synthase [10][11][12][13][14][15][16][17] or, alternatively, to shift this regulatory peptide from an inhibitory to a silent position on the enzyme [10,18,19]. The IF1 binding site was proposed to be located close to the C-terminus proximal DELSEED loop of the b-subunit [20], close to the catalytic site [21], at the a/b interface [22], or at the a/c interface [23]. A recent tridimensional model of the bovine MF 1 -IF1 complex drawn from radiocristallographic data showed IF1 bound at the a/b interface, and interacting weakly with c [24].The F 0 F 1 -IF1 interaction is m...

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ATP synthesis catalyzed by the mitochondrial F₁‐F₀ ATP synthase is not a reversal of its ATPase activity

Cited by 46 publications

References 39 publications

Complete Inhibition and Partial Re-activation of Single F1-ATPase Molecules by Tentoxin

Complete Inhibition and Partial Re-activation of Single F1-ATPase Molecules by Tentoxin

Energy-dependent Transformation of F0·F1-ATPase in Paracoccus denitrificans Plasma Membranes

Functional transitions of F₀F₁‐ATPase mediated by the inhibitory peptide IF1 in yeast coupled submitochondrial particles

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ATP synthesis catalyzed by the mitochondrial F1‐F0 ATP synthase is not a reversal of its ATPase activity

Cited by 46 publications

References 39 publications

Complete Inhibition and Partial Re-activation of Single F1-ATPase Molecules by Tentoxin

Complete Inhibition and Partial Re-activation of Single F1-ATPase Molecules by Tentoxin

Energy-dependent Transformation of F0·F1-ATPase in Paracoccus denitrificans Plasma Membranes

Functional transitions of F0F1‐ATPase mediated by the inhibitory peptide IF1 in yeast coupled submitochondrial particles

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ATP synthesis catalyzed by the mitochondrial F₁‐F₀ ATP synthase is not a reversal of its ATPase activity

Functional transitions of F₀F₁‐ATPase mediated by the inhibitory peptide IF1 in yeast coupled submitochondrial particles