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Trypanosoma brucei F1-ATPaseTrypanosoma brucei F1-ATPase
Structural highlights
Function[ATP18_TRYBB] Mitochondrial membrane ATP synthase (F(1)F(o) ATP synthase) produces ATP from ADP in the presence of a proton gradient across the membrane which is generated by electron transport complexes of the respiratory chain (PubMed:19436713, PubMed:29247468). F-type ATPases consist of two structural domains, F(1) - containing the extramembraneous catalytic core, and F(o) - containing the membrane proton channel, linked together by a central stalk and a peripheral stalk (PubMed:19436713, PubMed:29247468, PubMed:29440423). During catalysis, ATP synthesis in the catalytic domain of F(1) is coupled via a rotary mechanism of the central stalk subunits to proton translocation. Subunits alpha and beta form the catalytic core in F(1) (PubMed:19436713, PubMed:29440423). Rotation of the central stalk against the surrounding alpha(3)beta(3) subunits leads to hydrolysis of ATP in three separate catalytic sites on the beta subunits (Probable). Contrary to the procyclic, insect form that requires F(1)F(o) ATP synthase for ATP synthesis, the bloodstream form relies on ATP hydrolysis by F(1)F(o) ATP synthase to maintain its mitochondrial membrane potential (PubMed:29247468).[1] [2] [3] [ATPD_TRYBB] Mitochondrial membrane ATP synthase (F(1)F(o) ATP synthase) produces ATP from ADP in the presence of a proton gradient across the membrane which is generated by electron transport complexes of the respiratory chain (PubMed:19436713, PubMed:29247468). F-type ATPases consist of two structural domains, F(1) - containing the extramembraneous catalytic core, and F(o) - containing the membrane proton channel, linked together by a central stalk and a peripheral stalk (PubMed:19436713, PubMed:29247468, PubMed:29440423). During catalysis, ATP synthesis in the catalytic domain of F(1) is coupled via a rotary mechanism of the central stalk subunits to proton translocation. Subunits alpha and beta form the catalytic core in F(1) (PubMed:19436713, PubMed:29440423). Rotation of the central stalk against the surrounding alpha(3)beta(3) subunits leads to hydrolysis of ATP in three separate catalytic sites on the beta subunits (Probable). Contrary to the procyclic, insect form that requires F(1)F(o) ATP synthase for ATP synthesis, the bloodstream form relies on ATP hydrolysis by F(1)F(o) ATP synthase to maintain its mitochondrial membrane potential (PubMed:29247468).[4] [5] [6] [ATPA_TRYBB] Mitochondrial membrane ATP synthase (F(1)F(o) ATP synthase) produces ATP from ADP in the presence of a proton gradient across the membrane which is generated by electron transport complexes of the respiratory chain (PubMed:19436713, PubMed:29247468). F-type ATPases consist of two structural domains, F(1) - containing the extramembraneous catalytic core, and F(o) - containing the membrane proton channel, linked together by a central stalk and a peripheral stalk (PubMed:19436713, PubMed:29247468, PubMed:29440423). During catalysis, ATP synthesis in the catalytic domain of F(1) is coupled via a rotary mechanism of the central stalk subunits to proton translocation. Subunits alpha and beta form the catalytic core in F(1) (PubMed:19436713, PubMed:29440423). Rotation of the central stalk against the surrounding alpha(3)beta(3) subunits leads to hydrolysis of ATP in three separate catalytic sites on the beta subunits (Probable). Subunit alpha does not bear the catalytic high-affinity ATP-binding sites (PubMed:29440423). Contrary to the procyclic, insect form that requires F(1)F(o) ATP synthase for ATP synthesis, the bloodstream form relies on ATP hydrolysis by F(1)F(o) ATP synthase to maintain its mitochondrial membrane potential (PubMed:29247468).[7] [8] [9] [ATPB_TRYBB] Mitochondrial membrane ATP synthase (F(1)F(o) ATP synthase) produces ATP from ADP in the presence of a proton gradient across the membrane which is generated by electron transport complexes of the respiratory chain (PubMed:19436713, PubMed:29247468). F-type ATPases consist of two structural domains, F(1) - containing the extramembraneous catalytic core, and F(o) - containing the membrane proton channel, linked together by a central stalk and a peripheral stalk (PubMed:19436713, PubMed:29247468, PubMed:29440423). During catalysis, ATP synthesis in the catalytic domain of F(1) is coupled via a rotary mechanism of the central stalk subunits to proton translocation. Subunits alpha and beta form the catalytic core in F(1) (PubMed:19436713, PubMed:29440423). Rotation of the central stalk against the surrounding alpha(3)beta(3) subunits leads to hydrolysis of ATP in three separate catalytic sites on the beta subunits (Probable). Contrary to the procyclic, insect form that requires F(1)F(o) ATP synthase for ATP synthesis, the bloodstream form relies on ATP hydrolysis by F(1)F(o) ATP synthase to maintain its mitochondrial membrane potential (PubMed:29247468).[10] [11] [12] [ATP5E_TRYBB] Mitochondrial membrane ATP synthase (F(1)F(o) ATP synthase) produces ATP from ADP in the presence of a proton gradient across the membrane which is generated by electron transport complexes of the respiratory chain (PubMed:19436713, PubMed:29247468). F-type ATPases consist of two structural domains, F(1) - containing the extramembraneous catalytic core, and F(o) - containing the membrane proton channel, linked together by a central stalk and a peripheral stalk (PubMed:19436713, PubMed:29247468, PubMed:29440423). During catalysis, ATP synthesis in the catalytic domain of F(1) is coupled via a rotary mechanism of the central stalk subunits to proton translocation. Subunits alpha and beta form the catalytic core in F(1) (PubMed:19436713, PubMed:29440423). Rotation of the central stalk against the surrounding alpha(3)beta(3) subunits leads to hydrolysis of ATP in three separate catalytic sites on the beta subunits (Probable). Contrary to the procyclic, insect form that requires F(1)F(o) ATP synthase for ATP synthesis, the bloodstream form relies on ATP hydrolysis by F(1)F(o) ATP synthase to maintain its mitochondrial membrane potential (PubMed:29247468).[13] [14] [15] Publication Abstract from PubMedThe structures and functions of the components of ATP synthases, especially those subunits involved directly in the catalytic formation of ATP, are widely conserved in metazoans, fungi, eubacteria, and plant chloroplasts. On the basis of a map at 32.5-A resolution determined in situ in the mitochondria of Trypanosoma brucei by electron cryotomography, it has been proposed that the ATP synthase in this species has a noncanonical structure and different catalytic sites in which the catalytically essential arginine finger is provided not by the alpha-subunit adjacent to the catalytic nucleotide-binding site as in all species investigated to date, but rather by a protein, p18, found only in the euglenozoa. A crystal structure at 3.2-A resolution of the catalytic domain of the same enzyme demonstrates that this proposal is incorrect. In many respects, the structure is similar to the structures of F1-ATPases determined previously. The alpha3beta3-spherical portion of the catalytic domain in which the three catalytic sites are found, plus the central stalk, are highly conserved, and the arginine finger is provided conventionally by the alpha-subunits adjacent to each of the three catalytic sites found in the beta-subunits. Thus, the enzyme has a conventional catalytic mechanism. The structure differs from previous described structures by the presence of a p18 subunit, identified only in the euglenozoa, associated with the external surface of each of the three alpha-subunits, thereby elaborating the F1-domain. Subunit p18 is a pentatricopeptide repeat (PPR) protein with three PPRs and appears to have no function in the catalytic mechanism of the enzyme. ATP synthase from Trypanosoma brucei has an elaborated canonical F1-domain and conventional catalytic sites.,Montgomery MG, Gahura O, Leslie AGW, Zikova A, Walker JE Proc Natl Acad Sci U S A. 2018 Feb 27;115(9):2102-2107. doi:, 10.1073/pnas.1720940115. Epub 2018 Feb 12. PMID:29440423[16] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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