Subunit interactions in the F₁ adenosine triphosphatase from the thermophilic bacterium PS3 determined by chemical cross-linking

Abstract

Sone, N., Hou, C. & Bragg, P. D. (1986) Subunit interactions in the FI adenosine triphosphatase from the thermophilic bacterium PS3 determined by chemical cross-linking. Biochem. Cell Biol. 64, 229-237The arrangement of the subunits in TFI , the adenosine triphosphatase of the thermophilic bacterium PS3, has been investigated using bifunctional chemical cross-linking agents to covalently link adjacent subunits in the enzyme molecule. The cross-linked products resulting from the reaction of the enzyme with 2,2'-and 3,3'-dithiobis(succinimidyl propionate), 3,3'-dithiobis(su1-fosuccinimidyl propionate), le disuccinimidyl tartarate, le dimethyl suberimidate, le I-ethyl-3[3-dimtthylamino)propyl]carand 1,2:3,4-diepoxybutane were analyzed by sodium dodecyl sufate -polyacrylamide gel electrophoresis. Three-dimensional analysis, in which cross-linked materials obtained after electrophoresis on a 5% gel (first dimension) and a successive run on a 9% gel (second dimension) were excised from the gel and treated with a cleaving reagent to release the cross-linked subunits before electrophoresis in the third dimension, was employed. The following cross-linked dimers were identified: a a , u p , a y , p y , a s , and ye. Two trirners, a 2 6 and y a 6 , were recognized. The significance of these results is discussed in relationship to models for the arrangement of the subunits in the TF, molecule. Sone, N., Hou, C. & Bragg, P. D. (1986) Subunit interactions in the FI adenosine triphosphatase from the thermophilic bacterium PS3 determined by chemical cross-linking. Biochem. Cell Biol. 64, 229-237Utilisant des agents reticulants chimiques bifonctionnels pour lier de faqon covalente les sous-unites adjacentes dans la molecule enzymatique, nous avons examine la disposition des sous-unites dans le TFI , l'adenosine triphosphatase de la bacttrie thermophile PS3. Nous avons analysC par Clectrophorkse sur gel de polyacrylamide avec dodCcyl sulfate de sodium les produits dticults resultant de la reaction de l'enzyme avec le 2,2'-et le 3,3'-dithiobis(succinimidyl propionate), le 3,3'-dithiobis(su1-fosuccinimidyl propionate), le disuccinimidyl tartarate, le dimkthyl subtrimidate, le 1-tthyl-3[3-dim6thylamino)propyl]carbodiimide et le 1,2:3,4-dikpoxybutane. Nous avons effectuC une analyse tridimensionnelle au cours de laquelle les produits dticulCs obtenus aprks Clectrophorkse d'abord sur un gel 5% (premikre dimension) et ensuite sur un gel 9% (seconde dimension) ont Ct C coup& du gel et trait& avec un reactif de clivage pour libkrer les sous-unites rCticulees avant I'Clectrophorkse dans la troisikme dimension. Nous avons identifit les dimkres r6ticults suivants: a a , a p , cry, p y , a 6 et ye. Nous avons reconnu deux trimkres: a26 et y a 8 . NOUS discutons de I'importance de ces rtsultats en relation avec des modkles de la disposition des sous-unites dans la molCcule de TFI.[Traduit par la revue] IntroductionThe catalytic sites for ATP formation by oxidative or photophosphorylation in mitochondria, bacterial cell membranes, chloroplasts,...

Hybrid Rhodospirillum rubrumF0F1 ATP Synthases Containing Spinach Chloroplast F1 β or α and β Subunits Reveal the Essential Role of the α Subunit in ATP Synthesis and Tentoxin Sensitivity

“…Earlier biochemical evidence has shown that a readily formed disulfide link between the EcF 1 ␦ and one of the ␣ subunits did not inhibit ATPase activity (44,45). Furthermore, with bifunctional cross-linking reagents, ␣-␦ dimers and ␣-␣-␦ trimers, but not ␤-␦ dimers, were identified in EcF 1 (46) and TF 1 (47). The formation of such dimers and trimers as well as b-␦ and b-b dimers have recently been observed by crosslinking of introduced cysteine residues in EcF 0 F 1 ␣, ␦, and b subunits (48,49).…”