ATP Synthase with Its γ Subunit Reduced to the N-terminal Helix Can Still Catalyze ATP Synthesis

Abstract

ATP synthase uses a unique rotary mechanism to couple ATP synthesis and hydrolysis to transmembrane proton translocation. As part of the synthesis mechanism, the torque of the rotor has to be converted into conformational rearrangements of the catalytic binding sites on the stator to allow synthesis and release of ATP. The γ subunit of the rotor, which plays a central role in the energy conversion, consists of two long helices inside the central cavity of the stator cylinder plus a globular portion outside the cylinder. Here, we show that the N-terminal helix alone is able to fulfill the function of full-length γ in ATP synthesis as long as it connects to the rest of the rotor. This connection can occur via the ϵ subunit. No direct contact between γ and the c ring seems to be required. In addition, the results indicate that the ϵ subunit of the rotor exists in two different conformations during ATP synthesis and ATP hydrolysis. ATP synthase uses a unique rotary mechanism to couple ATP synthesis and hydrolysis to transmembrane proton translocation. As part of the synthesis mechanism, the torque of the rotor has to be converted into conformational rearrangements of the catalytic binding sites on the stator to allow synthesis and release of ATP. The γ subunit of the rotor, which plays a central role in the energy conversion, consists of two long helices inside the central cavity of the stator cylinder plus a globular portion outside the cylinder. Here, we show that the N-terminal helix alone is able to fulfill the function of full-length γ in ATP synthesis as long as it connects to the rest of the rotor. This connection can occur via the ϵ subunit. No direct contact between γ and the c ring seems to be required. In addition, the results indicate that the ϵ subunit of the rotor exists in two different conformations during ATP synthesis and ATP hydrolysis. F1Fo-ATP synthase is responsible for the bulk of ATP synthesis from ADP and Pi in most organisms. F1Fo-ATP synthase consists of the membrane-embedded Fo subcomplex with, in most bacteria, a subunit composition of ab2cn (with n = 10–15) and the peripheral F1 subcomplex, with a subunit composition of α3β3γδϵ. The energy necessary for ATP synthesis is derived from an electrochemical transmembrane proton (or, in some organisms, sodium ion) gradient. Proton flow, down the gradient, through Fo is coupled to ATP synthesis on F1 by a unique rotary mechanism. The protons flow through channels at the interface of a and c subunits, which drives rotation of the ring of c subunits. The cn ring, together with F1 subunits γ and ϵ, forms the rotor. Rotation of γ leads to conformational changes in the catalytic nucleotide-binding sites on the β subunits, where ADP and Pi are bound. The conformational changes result in formation and release of ATP. Thus, ATP synthase converts electrochemical energy, the proton gradient, into mechanical energy in the form of subunit rotation and back into chemical energy as ATP. In bacteria, under certain physiological conditions, the process can run in reverse. ATP is hydrolyzed to generate a transmembrane proton gradient that the bacterium requires for such functions as nutrient import and locomotion (for reviews, see Refs. 1Noji H. Yoshida M. J. Biol. Chem. 2001; 276: 1665-1668Abstract Full Text Full Text PDF PubMed Scopus (159) Google Scholar, 2Weber J. Senior A.E. FEBS Lett. 2003; 545: 61-70Crossref PubMed Scopus (240) Google Scholar, 3Wilkens S. Adv. Protein Chem. 2005; 71: 345-382Crossref PubMed Scopus (44) Google Scholar, 4Weber J. Biochim. Biophys. Acta. 2006; 1757: 1162-1170Crossref PubMed Scopus (52) Google Scholar, 5Nakamoto R.K. Baylis Scanlon J.A. Al-Shawi M.K. Arch. Biochem. Biophys. 2008; 476: 43-50Crossref PubMed Scopus (131) Google Scholar, 6Junge W. Sielaff H. Engelbrecht S. Nature. 2009; 459: 364-370Crossref PubMed Scopus (302) Google Scholar). F1 (or “F1-ATPase”) has three catalytic nucleotide-binding sites, located on the β subunits, at the interface with the adjacent α subunit. The catalytic sites have pronounced differences in their nucleotide-binding affinity. During rotational catalysis, the sites switch their affinities in a synchronized manner; the position of γ determines which catalytic site is the high affinity site (Kd1 in the nanomolar range), which site is the medium affinity site (Kd2 ≈ 1 μm), and which site is the low affinity site (Kd3 ≈ 30–100 μm; see Refs. 7Weber J. Wilke-Mounts S. Lee R.S. Grell E. Senior A.E. J. Biol. Chem. 1993; 268: 20126-20133Abstract Full Text PDF PubMed Google Scholar, 8Weber J. Senior A.E. Methods Enzymol. 2004; 380: 132-152Crossref PubMed Scopus (17) Google Scholar). Only the high affinity site is catalytically active (9Baylis Scanlon J.A. Al-Shawi M.K. Le N.P. Nakamoto R.K. Biochemistry. 2007; 46: 8785-8797Crossref PubMed Scopus (30) Google Scholar). In the original crystal structure of bovine mitochondrial F1 (10Abrahams J.P. Leslie A.G. Lutter R. Walker J.E. Nature. 1994; 370: 621-628Crossref PubMed Scopus (2764) Google Scholar), one of the three catalytic sites was filled with the ATP analog AMPPNP, 3The abbreviations used are: AMPPNP5′-adenylyl-β,γ-imidodiphosphateACMA9-amino-6-chloro-2-methoxyacridineAp5AP1,P5-di(adenosine-5′)pentaphosphate; TF1 or TF1Fo (instead of F1 and F1Fo, respectively) refer specifically to the enzyme from the thermophilic bacterium Bacillus PS3γ′truncated γ subunit. a second one with ADP (plus azide; see Ref. 11Bowler M.W. Montgomery M.G. Leslie A.G. Walker J.E. J. Biol. Chem. 2007; 282: 14238-14242Abstract Full Text Full Text PDF PubMed Scopus (164) Google Scholar), and the third site was empty. Hence, the β subunits are referred to as βTP, βDP, and βE, respectively. The high affinity site is located on the βTP subunit (12Mao H.Z. Weber J. Proc. Natl. Acad. Sci. U.S.A. 2007; 104: 18478-18483Crossref PubMed Scopus (32) Google Scholar). 5′-adenylyl-β,γ-imidodiphosphate 9-amino-6-chloro-2-methoxyacridine P1,P5-di(adenosine-5′)pentaphosphate; TF1 or TF1Fo (instead of F1 and F1Fo, respectively) refer specifically to the enzyme from the thermophilic bacterium Bacillus PS3 truncated γ subunit. The coupling process between ATP synthesis or hydrolysis on β and rotation of γ is not yet fully understood on a residue level. A number of point mutations at the interfaces between α or β and γ and between γ, ϵ, and c have been described that result in varying degrees of uncoupling (13Al-Shawi M.K. Nakamoto R.K. Biochemistry. 1997; 36: 12954-12960Crossref PubMed Scopus (38) Google Scholar, 14Ketchum C.J. Nakamoto R.K. J. Biol. Chem. 1998; 273: 22292-22297Abstract Full Text Full Text PDF PubMed Scopus (24) Google Scholar, 15Peskova Y.B. Nakamoto R.K. Biochemistry. 2000; 39: 11830-11836Crossref PubMed Scopus (22) Google Scholar, 16Andrews S.H. Peskova Y.B. Polar M.K. Herlihy V.B. Nakamoto R.K. Biochemistry. 2001; 40: 10664-10670Crossref PubMed Scopus (18) Google Scholar, 17Lowry D.S. Frasch W.D. Biochemistry. 2005; 44: 7275-7281Crossref PubMed Scopus (16) Google Scholar). Some mutations at these interfaces were found that abolish ATP synthesis or hydrolysis activity or both (18Greene M.D. Frasch W.D. J. Biol. Chem. 2003; 278: 51594-51598Abstract Full Text Full Text PDF PubMed Scopus (31) Google Scholar, 19Boltz K.W. Frasch W.D. Biochemistry. 2005; 44: 9497-9506Crossref PubMed Scopus (9) Google Scholar, 20Boltz K.W. Frasch W.D. Biochemistry. 2006; 45: 11190-11199Crossref PubMed Scopus (7) Google Scholar). Considering the pronounced effect of these point mutations, some of which were even conservative substitutions, it came as a surprise when it was recently shown that an “axle-less” γ, consisting just of the globular portion, with the portions of the N- and C-terminal helices that reach into the α3β3 cylinder removed, displayed ATP-driven rotation in the correct direction (21Furuike S. Hossain M.D. Maki Y. Adachi K. Suzuki T. Kohori A. Itoh H. Yoshida M. Kinosita Jr., K. Science. 2008; 319: 955-958Crossref PubMed Scopus (93) Google Scholar). Some reports have implicated the ϵ subunit (corresponding to the δ subunit in the mitochondrial enzyme) as being involved in coupling (15Peskova Y.B. Nakamoto R.K. Biochemistry. 2000; 39: 11830-11836Crossref PubMed Scopus (22) Google Scholar, 22Xiao Y. Metzl M. Mueller D.M. J. Biol. Chem. 2000; 275: 6963-6968Abstract Full Text Full Text PDF PubMed Scopus (20) Google Scholar, 23Duvezin-Caubet S. Caron M. Giraud M.F. Velours J. di Rago J.P. Proc. Natl. Acad. Sci. U.S.A. 2003; 100: 13235-13240Crossref PubMed Scopus (45) Google Scholar, 24Rondelez Y. Tresset G. Nakashima T. Kato-Yamada Y. Fujita H. Takeuchi S. Noji H. Nature. 2005; 433: 773-777Crossref PubMed Scopus (305) Google Scholar, 25Cipriano D.J. Dunn S.D. J. Biol. Chem. 2006; 281: 501-507Abstract Full Text Full Text PDF PubMed Scopus (46) Google Scholar). It was shown that ϵ exists in different conformations that vary in the folding and positioning of the C-terminal domain. The x-ray structure of the mitochondrial enzyme (26Gibbons C. Montgomery M.G. Leslie A.G. Walker J.E. Nat. Struct. Biol. 2000; 7: 1055-1061Crossref PubMed Scopus (437) Google Scholar) shows the two helices of the C-terminal domain folded back on each other like a hairpin and positioned close to the interface between γ and the c ring (“down” conformation). In the crystal structure of a γϵ complex from Escherichia coli the hairpin is unfolded (27Rodgers A.J. Wilce M.C. Nat. Struct. Biol. 2000; 7: 1051-1054Crossref PubMed Scopus (153) Google Scholar); when integrated into F1 or F1Fo, the C terminus would reach “up,” coming close to the DELSEED-loop of the α and/or β subunits. While in this up conformation the angle between both helices of the C-terminal domain of ϵ is ∼90°, it has been postulated that this domain might also exist in a fully extended up conformation, stretching close to the N terminus of γ, with helical regions replacing the turn between the two helices (28Yagi H. Kajiwara N. Tanaka H. Tsukihara T. Kato-Yamada Y. Yoshida M. Akutsu H. Proc. Natl. Acad. Sci. U.S.A. 2007; 104: 11233-11238Crossref PubMed Scopus (96) Google Scholar). Fixing ϵ in either up conformation by cross-linking to γ has been shown to impair ATP hydrolysis but not synthesis. Freezing ϵ in the down position inhibited neither reaction (29Tsunoda S.P. Rodgers A.J. Aggeler R. Wilce M.C. Yoshida M. Capaldi R.A. Proc. Natl. Acad. Sci. U.S.A. 2001; 98: 6560-6564Crossref PubMed Scopus (164) Google Scholar, 30Suzuki T. Murakami T. R. Suzuki J. S. Y. Yoshida M. J. Biol. Chem. 2003; 278: Full Text Full Text PDF PubMed Scopus Google Scholar). Here, we a that is just as as the rotation of an In ATP synthase from the thermophilic bacterium Bacillus with γ subunit where the globular domain and the C-terminal helix were consisting of just the N-terminal or PS3 is used and were able to of ATP synthesis. to the crystal structure (26Gibbons C. Montgomery M.G. Leslie A.G. Walker J.E. Nat. Struct. Biol. 2000; 7: 1055-1061Crossref PubMed Scopus (437) Google Scholar), the of the two γ not contact either with c or with ϵ in the down Thus, the that ATP synthesis was that ϵ in an up conformation forms a complex with the truncated γ, which is able to ATP synthesis. when the was with an ϵ where the C-terminal domain was removed, ATP synthesis was The functions of the γ and ϵ subunits be in of the which the for the F1Fo-ATP synthase from thermophilic Bacillus PS3 T. H. N. Suzuki J. Yoshida M. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar), was used to generate the mutations and In to generate TF1Fo by the we that the E. coli of full-length PS3 γ, by a in a this an site was of the This of the of the for γ on an second site is between the for γ and of the and the was The were in such a in to the a site would be or to were by the and were into E. coli which not E. coli ATP synthase D.J. J. PubMed Google Scholar). E. coli or was at for in medium from E. coli thermophilic were as described T. H. N. Suzuki J. Yoshida M. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar, A.E. Arch. Biochem. Biophys. PubMed Scopus Google Scholar). The of in E. coli was by as by with The of the was via an or an from The was a and of The the globular portion of γ, used to the of this portion of the in the was a from Suzuki and Yoshida and of or PS3 ATP synthase in was as described A.E. Biochem. J. PubMed Scopus Google Scholar). were as described N. Suzuki T. Weber J. J. Biol. Chem. 2009; Full Text Full Text PDF PubMed Scopus (32) Google Scholar). ATP synthesis activity in was as The used to the in 1 of the at a different the reaction the to be at this were in a and and at was to activity of the Jr., J.E. Biochemistry. PubMed Scopus Google Scholar). The reaction was by the of and of the reaction of were into of for The were at for on and for 1 at The of ATP was by the ATP was at in a In in the of the ATP synthesis was in and ATP synthesis in in of on ATP synthesis of of in a The ATP synthesis was in a and at of and of the were The reaction was by the of The but in the of the is by of the at and ATP-driven in was via of at a of and were Proton was by or ATP to a of 1 and by 1 The was and the was Protein of were by the J. Biol. Chem. Full Text PDF PubMed Google Scholar) bovine as The and the globular portion of γ and the C-terminal just a of the N-terminal helix the contact site between the truncated γ in the and the N-terminal domain of ϵ would be to a with would be between and the N-terminal domain of ϵ γ be able to reach the ring of c subunits would be located γ and ϵ in an ϵ subunit consisting of just the N-terminal the C-terminal domain was an E. coli and were as described under and an a from the globular domain of γ that this domain was from the γ and (for see an or an was used to the of TF1Fo in the the results are in The show that it is to generate a ATP In it has been on in that δ and ϵ subunits are for binding of TF1 to M. H. N. H. Y. Proc. Natl. Acad. Sci. U.S.A. PubMed Scopus Google Scholar). the of the to ATP synthesis in we on of E. coli with the As of the a enzyme was the as that of the which not ATP In TF1Fo either or the that γ requires N-terminal helix to effect the conformational changes in β to ATP synthesis. these we ATP synthesis by in the enzyme not show synthesis both γ displayed ATP synthesis to of the activity of the enzyme for see also the of the contact between ϵ in the down conformation and in the and the of with in the it that a complex between and the C-terminal domain of ϵ in the up conformation might be responsible for the ATP synthesis in the this we the γ with a of the C-terminal domain of ϵ, an As shown D.J. Dunn S.D. J. Biol. Chem. 2006; 281: 501-507Abstract Full Text Full Text PDF PubMed Scopus (46) Google Scholar), in enzyme with full-length γ the C-terminal domain of ϵ is not necessary for ATP of the domain in the in ATP synthesis was able to ATP that in this the between and the N-terminal domain of ϵ is to couple proton rotation of the c ring to ATP synthesis. In the to ATP synthesis 1 and The that the ATP synthesis in the of direct between and the N-terminal domain of ϵ, the C-terminal domain of ϵ can the N-terminal domain and that can role in ATP synthesis. with their ATP synthase the ATP hydrolysis activity of the was In the activity was of that of the at in the of the this was found for the enzyme the not ATP-driven proton not The activity is low to up a proton gradient the of the proton in ATP synthase in the of as for the that or of the γ subunit and/or of the ϵ subunit not with proton of the of of in a The results of the that the globular portion and the C-terminal helix of γ, together for of the of γ, are not for ATP synthesis The N-terminal domain of γ alone is to generate the conformational changes in the catalytic sites necessary for ATP synthesis and γ is in ATP synthesis is it was shown that γ this one consisting of just the globular portion, both the N-terminal and the C-terminal helix inside the α3β3 cylinder in the correct direction ATP hydrolysis (21Furuike S. Hossain M.D. Maki Y. Adachi K. Suzuki T. Kohori A. Itoh H. Yoshida M. Kinosita Jr., K. Science. 2008; 319: 955-958Crossref PubMed Scopus (93) Google Scholar). activity of subcomplex was not that of α3β3 (21Furuike S. Hossain M.D. Maki Y. Adachi K. Suzuki T. Kohori A. Itoh H. Yoshida M. Kinosita Jr., K. Science. 2008; 319: 955-958Crossref PubMed Scopus (93) Google Scholar), and the torque by ATP hydrolysis a portion of both helices inside the α3β3 cylinder was in the the torque of that of M.D. S. Maki Y. Adachi K. Suzuki T. Kohori A. Itoh H. Yoshida M. Kinosita Jr., K. Biophys. J. 2008; Full Text Full Text PDF PubMed Scopus Google Scholar). This the to that helix in the of the of plays a role in torque M.D. S. Maki Y. Adachi K. Suzuki T. Kohori A. Itoh H. Yoshida M. Kinosita Jr., K. Biophys. J. 2008; Full Text Full Text PDF PubMed Scopus Google Scholar). The results this a of torque is to effect the conformational changes in the β subunits necessary to and release and this torque is just the N-terminal helix of the of the (21Furuike S. Hossain M.D. Maki Y. Adachi K. Suzuki T. Kohori A. Itoh H. Yoshida M. Kinosita Jr., K. Science. 2008; 319: 955-958Crossref PubMed Scopus (93) Google Scholar, M.D. S. Maki Y. Adachi K. Suzuki T. Kohori A. Itoh H. Yoshida M. Kinosita Jr., K. Biophys. J. 2008; Full Text Full Text PDF PubMed Scopus Google Scholar) and the results it that the portion of γ that is most involved in coupling of and rotation is the of the N-terminal helix between and to the x-ray (10Abrahams J.P. Leslie A.G. Lutter R. Walker J.E. Nature. 1994; 370: 621-628Crossref PubMed Scopus (2764) Google Scholar, C. Montgomery M.G. Leslie A.G. Walker J.E. Nat. Struct. Biol. 2000; 7: 1055-1061Crossref PubMed Scopus (437) Google Scholar, Walker J.E. Leslie A.G. 2001; Full Text Full Text PDF PubMed Scopus Google Scholar), the of the N-terminal helix of γ with the α3β3 ring are with the a structure the in the C-terminal of and βE, as as with the subunit. The that the γ ATP synthesis the of the DELSEED-loop for coupling of rotation and is contact between the N-terminal helix of γ and βTP, which the catalytically active high affinity nucleotide-binding site (9Baylis Scanlon J.A. Al-Shawi M.K. Le N.P. Nakamoto R.K. Biochemistry. 2007; 46: 8785-8797Crossref PubMed Scopus (30) Google Scholar, H.Z. Weber J. Proc. Natl. Acad. Sci. U.S.A. 2007; 104: 18478-18483Crossref PubMed Scopus (32) Google Scholar, W. J. M. Proc. Natl. Acad. Sci. U.S.A. 2003; 100: PubMed Scopus Google Scholar). In some of the enzyme mechanism R.K. Baylis Scanlon J.A. Al-Shawi M.K. Arch. Biochem. Biophys. 2008; 476: 43-50Crossref PubMed Scopus (131) Google Scholar, W. M. 2005; Full Text Full Text PDF PubMed Scopus Google Scholar, H.Z. Weber J. J. Biol. Chem. 2008; Full Text Full Text PDF PubMed Scopus Google Scholar), a function of the γ subunit in ATP synthesis is to the torque by proton rotation to the βTP subunit to release the ATP. results for this Rotation of the N-terminal helix of γ by in ATP synthesis direction the portion of the helix in contact with the βTP subunit and it This the DELSEED-loop and it to the subunit and it into conformation, ATP. No other of γ for the N-terminal helix to be for this just as of the the role of the ϵ subunit. It been shown that the C-terminal domain of ϵ can different with different the between the different conformations was found to be by R. Murakami T. S. Kato-Yamada Y. Suzuki T. Yoshida M. J. Biol. Chem. 2005; Full Text Full Text PDF PubMed Scopus Google Scholar). Here, we that ϵ is in an up position during ATP synthesis. in the contact with the N-terminal domain of ϵ the enzyme can that the C-terminal domain of ϵ in the up conformation might to the rest of the rotor. of the C-terminal domain of ϵ ATP synthesis. the two up conformations of the C-terminal domain of ϵ or the conformation by x-ray structure (27Rodgers A.J. Wilce M.C. Nat. Struct. Biol. 2000; 7: 1051-1054Crossref PubMed Scopus (153) Google Scholar) is to form a complex with the N-terminal domain of γ by a different position in the of the rest of γ, it seems to have contact with the C-terminal domain of ϵ in this In cross-linking T. Murakami T. R. Suzuki J. S. Y. Yoshida M. J. Biol. Chem. 2003; 278: Full Text Full Text PDF PubMed Scopus Google Scholar) the that the C terminus of ϵ in a fully extended conformation close to the N terminus of an between the C-terminal helix of ϵ and the N-terminal helix of γ has been in the E. coli enzyme T. Scholar). As the with indicate that ϵ in the of portion of γ, ATP synthesis. It is to the C-terminal domain of ϵ also the between and the N-terminal domain of ϵ in the ATP at for it be into that for the enzyme of the C-terminal domain of ϵ ATP at in the in While has of the synthesis activity of the has of the activity of Thus, one that in this as the C-terminal domain of ϵ to the of the rotor on the crystal structure of the E. coli γϵ complex (28Yagi H. Kajiwara N. Tanaka H. Tsukihara T. Kato-Yamada Y. Yoshida M. Akutsu H. Proc. Natl. Acad. Sci. U.S.A. 2007; 104: 11233-11238Crossref PubMed Scopus (96) Google Scholar), direct between and the N-terminal domain of ϵ might and of between the of and the of and between the of and the of It be that the γ two and which were as for high affinity binding of γ to the c ring Y. K. T. FEBS J. 2008; 275: PubMed Scopus Google Scholar). As for other in ATP synthase J. Wilke-Mounts S. Senior A.E. J. Biol. Chem. 2003; 278: Full Text Full Text PDF PubMed Scopus Google Scholar), the high binding affinity between full-length γ and the c ring to be not but an of ATP the down conformation of ϵ, by direct binding to ϵ (28Yagi H. Kajiwara N. Tanaka H. Tsukihara T. Kato-Yamada Y. Yoshida M. Akutsu H. Proc. Natl. Acad. Sci. U.S.A. 2007; 104: 11233-11238Crossref PubMed Scopus (96) Google Scholar). ϵ in this position by cross-linking of the activity by ϵ (29Tsunoda S.P. Rodgers A.J. Aggeler R. Wilce M.C. Yoshida M. Capaldi R.A. Proc. Natl. Acad. Sci. U.S.A. 2001; 98: 6560-6564Crossref PubMed Scopus (164) Google Scholar). Thus, the down conformation to be the one that ϵ during ATP hydrolysis. two different of ϵ for ATP synthesis and hydrolysis has it that the for ATP synthesis and hydrolysis not necessary have to be the of each other J. Biol. 2000; PubMed Google Scholar, Suzuki T. Yoshida M. Biochim. Biophys. Acta. 2006; 1757: PubMed Scopus Google Scholar). this one of the during ATP the to ADP in the of an of ATP J. Senior A.E. FEBS Lett. 2003; 545: 61-70Crossref PubMed Scopus (240) Google Scholar, J. Senior A.E. Biochim. Biophys. Acta. 2000; PubMed Scopus Google Scholar). ATP hydrolysis conditions, is catalytic site that ADP with a affinity at in the of Pi H.Z. W.D. Weber J. FEBS Lett. 2006; PubMed Scopus (7) Google Scholar). ϵ in the up position might the affinities for a site that It is that ϵ not ATP synthesis by (28Yagi H. Kajiwara N. Tanaka H. Tsukihara T. Kato-Yamada Y. Yoshida M. Akutsu H. Proc. Natl. Acad. Sci. U.S.A. 2007; 104: 11233-11238Crossref PubMed Scopus (96) Google Scholar, Suzuki T. Yoshida M. J. Biol. Chem. 2007; 282: Full Text Full Text PDF PubMed Scopus Google Scholar), it is to in of this As we show that has ATP synthesis activity that the C-terminal domain of ϵ, which is in the is ATP synthesis. In one in the role of the ϵ subunit is the that ϵ from different ATP the function of ϵ in the from E. coli and Bacillus PS3 is not the in E. coli ATP synthase or the of of activity is a of ATP up to D.J. Dunn S.D. J. Biol. Chem. 2006; 281: 501-507Abstract Full Text Full Text PDF PubMed Scopus (46) Google Scholar, J. Dunn S.D. Senior A.E. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). In in the PS3 enzyme the is at low ATP Y. M. K. T. Yoshida M. J. Biol. Chem. Full Text Full Text PDF PubMed Scopus Google Scholar). it be that the results recently (21Furuike S. Hossain M.D. Maki Y. Adachi K. Suzuki T. Kohori A. Itoh H. Yoshida M. Kinosita Jr., K. Science. 2008; 319: 955-958Crossref PubMed Scopus (93) Google Scholar) and the of ATP synthase being from and or J.E. Chem. 268: Scholar, Nat. 2007; PubMed Scopus Google Scholar). that ATP synthase some with of γ, that of structure full-length γ can as a rotor in ATP