Ground State Structure of F1-ATPase from Bovine Heart Mitochondria at 1.9 Aå Resolution

The structure of bovine F1-ATPase, crystallized in the presence of AMP-PNP and ADP, but in the absence of azide, has been determined at 1.9Aå resolution. This structure has been compared with the previously described structure of bovine F1-ATPase determined at 1.95Aå resolution with crystals grown under the same conditions but in the presence of azide. The two structures are extremely similar, but they differ in the nucleotides that are bound to the catalytic site in the βDP-subunit. In the present structure, the nucleotide binding sites in the βDP- and βTP-subunits are both occupied by AMP-PNP, whereas in the earlier structure, the βTP site was occupied by AMP-PNP and the βDP site by ADP, where its binding is enhanced by a bound azide ion. Also, the conformation of the side chain of the catalytically important residue, αArg-373 differs in the βDP- and βTP-subunits. Thus, the structure with bound azide represents the ADP inhibited state of the enzyme, and the new structure represents a ground state intermediate in the active catalytic cycle of ATP hydrolysis. The structure of bovine F1-ATPase, crystallized in the presence of AMP-PNP and ADP, but in the absence of azide, has been determined at 1.9Aå resolution. This structure has been compared with the previously described structure of bovine F1-ATPase determined at 1.95Aå resolution with crystals grown under the same conditions but in the presence of azide. The two structures are extremely similar, but they differ in the nucleotides that are bound to the catalytic site in the βDP-subunit. In the present structure, the nucleotide binding sites in the βDP- and βTP-subunits are both occupied by AMP-PNP, whereas in the earlier structure, the βTP site was occupied by AMP-PNP and the βDP site by ADP, where its binding is enhanced by a bound azide ion. Also, the conformation of the side chain of the catalytically important residue, αArg-373 differs in the βDP- and βTP-subunits. Thus, the structure with bound azide represents the ADP inhibited state of the enzyme, and the new structure represents a ground state intermediate in the active catalytic cycle of ATP hydrolysis. Our current understanding of the molecular mechanism of F1-ATPase is based on the structural analysis by x-ray crystallography of the enzyme from bovine heart mitochondria. The first high resolution structure (1Abrahams J.P. Leslie A.G.W. Lutter R. Walker J.E. Nature. 1994; 370: 621-628Crossref PubMed Scopus (2736) Google Scholar), now known as the “reference” structure, determined at 2.8 Aå resolution with crystals grown in the presence of both ADP and the nonhydrolyzable ATP analog AMP-PNP, 3The abbreviation used is: AMP-PNP, adenosine 5′-(β,γ-imino)triphosphate. 3The abbreviation used is: AMP-PNP, adenosine 5′-(β,γ-imino)triphosphate. showed that the three noncatalytic α-subunits and the three catalytic β-subunits are arranged in alternation around an asymmetric α-helical structure in the single γ-subunit. The α- and β-subunits have similar folds consisting of an N-terminal domain with six β-strands, a central nucleotide binding domain made of both α-helices and β-strands and an α-helical C-terminal domain containing six α-helices in β-subunits and seven in α-subunits. Because of the asymmetry of the γ-subunit, the catalytic β-subunits adopt different conformations with different nucleotide occupancies. Two of them have similar conformations, but one, designated as βDP, contains bound ADP, and the second, βTP, has bound AMP-PNP. The third has adopted a radically different conformation in which the nucleotide binding domain has been disrupted by an outward hinging movement of part of the domain and the attached C-terminal domain in response to the curvature of the central α-helical structure of the γ-subunit. This β-subunit has no bound nucleotide, and so it is known as the “empty” or open state, designated as βE. To explain the interconversion of catalytic sites through “tight,” “loose,” and “open” states required by a binding change mechanism of catalysis of ATP hydrolysis by F1-ATPase (2Boyer P.D. Biochim. Biophys. Acta. 1993; 1140: 215-250Crossref PubMed Scopus (913) Google Scholar), it was proposed that the interconversion of sites is effected by a mechanical rotation of the γ-subunit, each 360° rotation taking each β-subunit through the three states and thereby hydrolyzing three ATP molecules. It was shown subsequently that during ATP hydrolysis, either in an α3β3γ complex or in the intact F1Fo-ATPase, that the direction of rotation is counterclockwise (as viewed from the membrane domain of the enzyme) during ATP hydrolysis and clockwise during ATP synthesis (3Noji H. Yasuda R. Yoshida M. Kinosita Jr., K. Nature. 1997; 386: 299-302Crossref PubMed Scopus (1942) Google Scholar, 4Sambongi Y. Iko Y. Tanabe M. Omote H. Iwamoto-Kihara Y. M. PubMed Scopus Google This first structure of bovine F1-ATPase was as a state in the active catalytic the state of the enzyme, or The crystals used in analysis grown in the presence of azide, to during the of in the presence of ADP, azide is an of F1-ATPase 1994; PubMed Google Scholar), but of the resolution of the its presence was in the in a structure at Aå determined with crystals grown under conditions to used in the first structural azide was in the Leslie A.G.W. Walker J.E. PubMed Scopus Google It is the of its central with the of ADP and the of its two with in the of the nucleotide binding site and with the catalytically residue, azide to the binding of ADP to the βDP site and to the state of the the present crystals of bovine F1-ATPase grown in the presence of both ADP and AMP-PNP under conditions to that azide was The structure of complex determined at Aå resolution in the presence of both ADP and AMP-PNP, both the βTP and βDP nucleotide binding sites occupied by AMP-PNP. described structure is the to of an intermediate in the catalytic cycle of ATP hydrolysis by the and of the resolution are shown in the resolution are shown in is at the to Aå is as in the of the the resolution are shown in where is the of the resolution are shown in where and are the and structure where and are the and structure and is the of from in the resolution are shown in The is at the to Aå is as in the of the where is the of where and are the and structure where and are the and structure and is the of from in in a new and F1-ATPase was as described previously R. J.P. Leslie A.G.W. Walker J.E. 1993; PubMed Scopus Google Scholar), that the was by a and was in the of bovine F1-ATPase was in of F1-ATPase grown in with molecular of AMP-PNP, ADP, and in was to the and the was The of AMP-PNP, ADP, and was with the same containing from in was in of in a during in a of of from in a conditions of crystals of bovine F1-ATPase Leslie A.G.W. Walker J.E. PubMed Scopus Google the crystals in a of and at the crystals to Aå resolution on a from at at the The with A.G.W. and on and from the 1994; PubMed Scopus Google and and of the structure was by molecular with 1997; Scopus Google the structure Leslie A.G.W. Walker J.E. PubMed Scopus Google as a ADP and AMP-PNP as bound in and The was with 1997; PubMed Scopus Google with with K. PubMed Scopus Google with 1993; PubMed Google was with K. PubMed Scopus Google Scholar), and and with The Google of the catalytic sites in the βDP- and βTP-subunits in the structure of the The is in and the βDP and βTP catalytic sites are and In the is from an similar to that shown in In the the movement of αArg-373 by a the in the βDP catalytic site is of in the of the of the to the in the structures of bovine F1-ATPase and in In the bovine enzyme, the side chain of has two conformations in each at The of the side chain of in the enzyme is of F1-ATPase with in the of with the crystals of bovine F1-ATPase grown in the presence of azide Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar), the of the present crystals by to to which is an high resolution a and The crystals to the are a and and is complex in the asymmetric The structure, known as was by molecular to structure of F1-ATPase inhibited with azide is known as and are in The contains the and βTP βDP and and and and The of the of the in the a by the central and as has been in structures Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar, Walker J.E. Leslie A.G.W. PubMed Scopus Google the of the by Aå to a of Aå to the domain of the in structures with a of Aå are of and the of AMP-PNP in the the βDP- and The noncatalytic nucleotide binding sites AMP-PNP Thus, the in the and structures differ in so as the ADP and azide and the AMP-PNP. conformations differ the of is and the of the α- and and catalytic side are similar The the two F1-ATPase is βDP binding site in the structure of the F1-ATPase from bovine heart mitochondria. The is in The the at its in the is shown as a The ADP and αArg-373 are shown as a at The and the catalytic and a of the of the of the in the structure but the two sites In the a movement of the of αArg-373 the of Aå to the the of AMP-PNP and it by the that is by In the in the has Aå to the in the of the structure and have been previously in the in the structure of bovine F1-ATPase where is bound to both the βDP and βTP sites R. K. Leslie A.G.W. Walker J.E. PubMed Scopus Google of the nucleotide binding sites in the βDP- and βTP-subunits in the structure of the The are in and and the are shown as the structure of the F1-ATPase from has been described at 2.8 Aå resolution based on crystals grown in the presence of AMP-PNP and ADP and in the absence of azide Walker J.E. Leslie A.G.W. PubMed Scopus Google In structure, AMP-PNP is bound to both the βDP- and βTP-subunits. of the structures of the of the of the bovine F1-ATPase and the F1-ATPase that the of the nucleotides and of the side in the nucleotide binding sites are similar of αArg-373 in the of the F1-ATPase has that the in the catalytic has two conformations, each at and conformation of the side chain of is from the catalytic site in the and the is The conformation is similar to the conformation of the side chain of in F1-ATPase Walker J.E. Leslie A.G.W. PubMed Scopus Google Scholar), which is in the of a ion. It that the side chain in the bovine enzyme the two conformations and the is bound in a similar in the bovine structure is its during of the bovine enzyme was that in the of the of the βDP- and in structure of bovine F1-ATPase described where AMP-PNP is bound in to ADP to the nucleotide binding sites in both the βDP- and the the two and the AMP-PNP ADP at the of nucleotides in the are with the in the enzyme, which that AMP-PNP and ATP have a both sites ADP 1997; PubMed Scopus Google Scholar, 1993; PubMed Google in of the structures that have been described of the bovine F1-ATPase (1Abrahams J.P. Leslie A.G.W. Lutter R. Walker J.E. Nature. 1994; 370: 621-628Crossref PubMed Scopus (2736) Google Scholar, Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar, Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar, R. K. Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar, J.P. Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar, Leslie A.G.W. K. Walker J.E. PubMed Scopus Google Scholar, J.P. Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar, K. Leslie A.G.W. Walker J.E. PubMed Scopus Google and in that of the enzyme Walker J.E. Leslie A.G.W. PubMed Scopus Google Scholar), the βDP- and binding sites are to each This structural the structure of F1-ATPase is the of βDP- and βTP-subunits with α-subunits they different in the structure to the and they are to different of the γ-subunit. structural βDP- and βTP-subunits them as of structural the current structure and that determined in the presence of azide Leslie A.G.W. Walker J.E. PubMed Scopus Google that the βDP and the βTP ADP and azide but it AMP-PNP In the βTP site ADP and azide, but it has a high AMP-PNP. in both the current structure and in the structure R. K. Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar), the in the is to the of ATP its in the in a state analog structure in the presence of ADP and structure K. Leslie A.G.W. Walker J.E. PubMed Scopus Google the state analog of ATP hydrolysis has in the βDP whereas ATP is bound to the This and the that the ATP bound to the and the ATP bound to the is the nucleotide that is to the state and hydrolysis at site to the of and the of the the structure of the F1-ATPase described represents a of three different structures of β-subunits that in the ground state of the catalytic cycle of ATP hydrolysis by structure and that of it is that the structure the structure of represents a state to the state of the enzyme and that conformation is an of an intermediate in the active catalytic Our current understanding of the molecular mechanism of F1-ATPase is based on the structural analysis by x-ray crystallography of the enzyme from bovine heart mitochondria. The first high resolution structure (1Abrahams J.P. Leslie A.G.W. Lutter R. Walker J.E. Nature. 1994; 370: 621-628Crossref PubMed Scopus (2736) Google Scholar), now known as the “reference” structure, determined at 2.8 Aå resolution with crystals grown in the presence of both ADP and the nonhydrolyzable ATP analog AMP-PNP, 3The abbreviation used is: AMP-PNP, adenosine 5′-(β,γ-imino)triphosphate. 3The abbreviation used is: AMP-PNP, adenosine 5′-(β,γ-imino)triphosphate. showed that the three noncatalytic α-subunits and the three catalytic β-subunits are arranged in alternation around an asymmetric α-helical structure in the single γ-subunit. The α- and β-subunits have similar folds consisting of an N-terminal domain with six β-strands, a central nucleotide binding domain made of both α-helices and β-strands and an α-helical C-terminal domain containing six α-helices in β-subunits and seven in α-subunits. Because of the asymmetry of the γ-subunit, the catalytic β-subunits adopt different conformations with different nucleotide occupancies. Two of them have similar conformations, but one, designated as βDP, contains bound ADP, and the second, βTP, has bound AMP-PNP. The third has adopted a radically different conformation in which the nucleotide binding domain has been disrupted by an outward hinging movement of part of the domain and the attached C-terminal domain in response to the curvature of the central α-helical structure of the γ-subunit. This β-subunit has no bound nucleotide, and so it is known as the “empty” or open state, designated as βE. To explain the interconversion of catalytic sites through “tight,” “loose,” and “open” states required by a binding change mechanism of catalysis of ATP hydrolysis by F1-ATPase (2Boyer P.D. Biochim. Biophys. Acta. 1993; 1140: 215-250Crossref PubMed Scopus (913) Google Scholar), it was proposed that the interconversion of sites is effected by a mechanical rotation of the γ-subunit, each 360° rotation taking each β-subunit through the three states and thereby hydrolyzing three ATP molecules. It was shown subsequently that during ATP hydrolysis, either in an α3β3γ complex or in the intact F1Fo-ATPase, that the direction of rotation is counterclockwise (as viewed from the membrane domain of the enzyme) during ATP hydrolysis and clockwise during ATP synthesis (3Noji H. Yasuda R. Yoshida M. Kinosita Jr., K. Nature. 1997; 386: 299-302Crossref PubMed Scopus (1942) Google Scholar, 4Sambongi Y. Iko Y. Tanabe M. Omote H. Iwamoto-Kihara Y. M. PubMed Scopus Google This first structure of bovine F1-ATPase was as a state in the active catalytic the state of the enzyme, or The crystals used in analysis grown in the presence of azide, to during the of in the presence of ADP, azide is an of F1-ATPase 1994; PubMed Google Scholar), but of the resolution of the its presence was in the in a structure at Aå determined with crystals grown under conditions to used in the first structural azide was in the Leslie A.G.W. Walker J.E. PubMed Scopus Google It is the of its central with the of ADP and the of its two with in the of the nucleotide binding site and with the catalytically residue, azide to the binding of ADP to the βDP site and to the state of the In the present crystals of bovine F1-ATPase grown in the presence of both ADP and AMP-PNP under conditions to that azide was The structure of complex determined at Aå resolution in the presence of both ADP and AMP-PNP, both the βTP and βDP nucleotide binding sites occupied by AMP-PNP. described structure is the to of an intermediate in the catalytic cycle of ATP hydrolysis by the and F1-ATPase was as described previously R. J.P. Leslie A.G.W. Walker J.E. 1993; PubMed Scopus Google Scholar), that the was by a and was in the of bovine F1-ATPase was in of F1-ATPase grown in with molecular of AMP-PNP, ADP, and in was to the and the was The of AMP-PNP, ADP, and was with the same containing from in was in of in a during in a of of from in a conditions of crystals of bovine F1-ATPase Leslie A.G.W. Walker J.E. PubMed Scopus Google the crystals in a of and at the crystals to Aå resolution on a from at at the The with A.G.W. and on and from the 1994; PubMed Scopus Google and and of the structure was by molecular with 1997; Scopus Google the structure Leslie A.G.W. Walker J.E. PubMed Scopus Google as a ADP and AMP-PNP as bound in and The was with 1997; PubMed Scopus Google with with K. PubMed Scopus Google with 1993; PubMed Google was with K. PubMed Scopus Google Scholar), and and with The Google of the of the to the in the structures of bovine F1-ATPase and in In the bovine enzyme, the side chain of has two conformations in each at The of the side chain of in the enzyme is and F1-ATPase was as described previously R. J.P. Leslie A.G.W. Walker J.E. 1993; PubMed Scopus Google Scholar), that the was by a and was in the of bovine F1-ATPase was in of F1-ATPase grown in with molecular of AMP-PNP, ADP, and in was to the and the was The of AMP-PNP, ADP, and was with the same containing from in was in of in a during in a of of from in a conditions of crystals of bovine F1-ATPase Leslie A.G.W. Walker J.E. PubMed Scopus Google the crystals in a of and at K. the crystals to Aå resolution on a from at at the The with A.G.W. and on and from the 1994; PubMed Scopus Google and and of the structure was by molecular with 1997; Scopus Google the structure Leslie A.G.W. Walker J.E. PubMed Scopus Google as a ADP and AMP-PNP as bound in and The was with 1997; PubMed Scopus Google with with K. PubMed Scopus Google with 1993; PubMed Google was with K. PubMed Scopus Google Scholar), and and with The Google of F1-ATPase with in the of with the crystals of bovine F1-ATPase grown in the presence of azide Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar), the of the present crystals by to to which is an high resolution a and The crystals to the are a and and is complex in the asymmetric The structure, known as was by molecular to structure of F1-ATPase inhibited with azide is known as and are in The contains the and βTP βDP and and and and The of the of the in the a by the central and as has been in structures Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar, Walker J.E. Leslie A.G.W. PubMed Scopus Google the of the by Aå to a of Aå to the domain of the in structures with a of Aå are of and the of AMP-PNP in the the βDP- and The noncatalytic nucleotide binding sites AMP-PNP Thus, the in the and structures differ in so as the ADP and azide and the AMP-PNP. conformations differ the of is and the of the α- and and catalytic side are similar The the two F1-ATPase is of the of the of the in the structure but the two sites In the a movement of the of αArg-373 the of Aå to the the of AMP-PNP and it by the that is by In the in the has Aå to the in the of the structure and have been previously in the in the structure of bovine F1-ATPase where is bound to both the βDP and βTP sites R. K. Leslie A.G.W. Walker J.E. PubMed Scopus Google of the nucleotide binding sites in the βDP- and βTP-subunits in the structure of the The are in and and the are shown as the structure of the F1-ATPase from has been described at 2.8 Aå resolution based on crystals grown in the presence of AMP-PNP and ADP and in the absence of azide Walker J.E. Leslie A.G.W. PubMed Scopus Google In structure, AMP-PNP is bound to both the βDP- and βTP-subunits. of the structures of the of the of the bovine F1-ATPase and the F1-ATPase that the of the nucleotides and of the side in the nucleotide binding sites are similar of αArg-373 in the of the F1-ATPase has that the in the catalytic has two conformations, each at and conformation of the side chain of is from the catalytic site in the and the is The conformation is similar to the conformation of the side chain of in F1-ATPase Walker J.E. Leslie A.G.W. PubMed Scopus Google Scholar), which is in the of a ion. It that the side chain in the bovine enzyme the two conformations and the is bound in a similar in the bovine structure is its during of the bovine enzyme was that in the of the of the βDP- and in structure of bovine F1-ATPase described where AMP-PNP is bound in to ADP to the nucleotide binding sites in both the βDP- and the the two and the AMP-PNP ADP at the of nucleotides in the are with the in the enzyme, which that AMP-PNP and ATP have a both sites ADP 1997; PubMed Scopus Google Scholar, 1993; PubMed Google in of the structures that have been described of the bovine F1-ATPase (1Abrahams J.P. Leslie A.G.W. Lutter R. Walker J.E. Nature. 1994; 370: 621-628Crossref PubMed Scopus (2736) Google Scholar, Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar, Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar, R. K. Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar, J.P. Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar, Leslie A.G.W. K. Walker J.E. PubMed Scopus Google Scholar, J.P. Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar, K. Leslie A.G.W. Walker J.E. PubMed Scopus Google and in that of the enzyme Walker J.E. Leslie A.G.W. PubMed Scopus Google Scholar), the βDP- and binding sites are to each This structural the structure of F1-ATPase is the of βDP- and βTP-subunits with α-subunits they different in the structure to the and they are to different of the γ-subunit. structural βDP- and βTP-subunits them as of structural the current structure and that determined in the presence of azide Leslie A.G.W. Walker J.E. PubMed Scopus Google that the βDP and the βTP ADP and azide but it AMP-PNP In the βTP site ADP and azide, but it has a high AMP-PNP. in both the current structure and in the structure R. K. Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar), the in the is to the of ATP its in the in a state analog structure in the presence of ADP and structure K. Leslie A.G.W. Walker J.E. PubMed Scopus Google the state analog of ATP hydrolysis has in the βDP whereas ATP is bound to the This and the that the ATP bound to the and the ATP bound to the is the nucleotide that is to the state and hydrolysis at site to the of and the of the the structure of the F1-ATPase described represents a of three different structures of β-subunits that in the ground state of the catalytic cycle of ATP hydrolysis by structure and that of it is that the structure the structure of represents a state to the state of the enzyme and that conformation is an of an intermediate in the active catalytic The of F1-ATPase with in the of with the crystals of bovine F1-ATPase grown in the presence of azide Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar), the of the present crystals by to to which is an high resolution a and The crystals to the are a and and is complex in the asymmetric The structure, known as was by molecular to structure of F1-ATPase inhibited with azide is known as and are in The contains the and βTP βDP and and and and The of the of the in the a by the central and as has been in structures Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar, Walker J.E. Leslie A.G.W. PubMed Scopus Google the of the by Aå to a of Aå to the domain of the in structures with a of Aå are of and the of AMP-PNP in the the βDP- and The noncatalytic nucleotide binding sites AMP-PNP Thus, the in the and structures differ in so as the ADP and azide and the AMP-PNP. conformations differ the of is and the of the α- and and catalytic side are similar The the two F1-ATPase is of the of the of the in the structure but the two sites In the a movement of the of αArg-373 the of Aå to the the of AMP-PNP and it by the that is by In the in the has Aå to the in the of the structure and have been previously in the in the structure of bovine F1-ATPase where is bound to both the βDP and βTP sites R. K. Leslie A.G.W. Walker J.E. PubMed Scopus Google the structure of the F1-ATPase from has been described at 2.8 Aå resolution based on crystals grown in the presence of AMP-PNP and ADP and in the absence of azide Walker J.E. Leslie A.G.W. PubMed Scopus Google In structure, AMP-PNP is bound to both the βDP- and βTP-subunits. of the structures of the of the of the bovine F1-ATPase and the F1-ATPase that the of the nucleotides and of the side in the nucleotide binding sites are similar of αArg-373 in the of the F1-ATPase has that the in the catalytic has two conformations, each at and conformation of the side chain of is from the catalytic site in the and the is The conformation is similar to the conformation of the side chain of in F1-ATPase Walker J.E. Leslie A.G.W. PubMed Scopus Google Scholar), which is in the of a ion. It that the side chain in the bovine enzyme the two conformations and the is bound in a similar in the bovine structure is its during of the bovine enzyme was that in the of the of the βDP- and in structure of bovine F1-ATPase described where AMP-PNP is bound in to ADP to the nucleotide binding sites in both the βDP- and the the two and the AMP-PNP ADP at the of nucleotides in the are with the in the enzyme, which that AMP-PNP and ATP have a both sites ADP 1997; PubMed Scopus Google Scholar, 1993; PubMed Google in of the structures that have been described of the bovine F1-ATPase (1Abrahams J.P. Leslie A.G.W. Lutter R. Walker J.E. Nature. 1994; 370: 621-628Crossref PubMed Scopus (2736) Google Scholar, Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar, Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar, R. K. Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar, J.P. Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar, Leslie A.G.W. K. Walker J.E. PubMed Scopus Google Scholar, J.P. Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar, K. Leslie A.G.W. Walker J.E. PubMed Scopus Google and in that of the enzyme Walker J.E. Leslie A.G.W. PubMed Scopus Google Scholar), the βDP- and binding sites are to each This structural the structure of F1-ATPase is the of βDP- and βTP-subunits with α-subunits they different in the structure to the and they are to different of the γ-subunit. structural βDP- and βTP-subunits them as of structural the current structure and that determined in the presence of azide Leslie A.G.W. Walker J.E. PubMed Scopus Google that the βDP and the βTP ADP and azide but it AMP-PNP In the βTP site ADP and azide, but it has a high AMP-PNP. in both the current structure and in the structure R. K. Leslie A.G.W. Walker J.E. PubMed Scopus Google Scholar), the in the is to the of ATP its in the in a state analog structure in the presence of ADP and structure K. Leslie A.G.W. Walker J.E. PubMed Scopus Google the state analog of ATP hydrolysis has in the βDP whereas ATP is bound to the This and the that the ATP bound to the and the ATP bound to the is the nucleotide that is to the state and hydrolysis at site to the of and the of the Thus, the structure of the F1-ATPase described represents a of three different structures of β-subunits that in the ground state of the catalytic cycle of ATP hydrolysis by structure and that of it is that the structure the structure of represents a state to the state of the enzyme and that conformation is an of an intermediate in the active catalytic the at the with with with