The peripheral stalk of the mitochondrial ATP synthase

Abstract

The peripheral stalk of F-ATPases is an essential component of these enzymes. It extends from the membrane distal point of the F1 catalytic domain along the surface of the F1 domain with subunit a in the membrane domain. Then, it reaches down some 45 A to the membrane surface, and traverses the membrane, where it is associated with the a-subunit. Its role is to act as a stator to hold the catalytic alpha3beta3 subcomplex and the a-subunit static relative to the rotary element of the enzyme, which consists of the c-ring in the membrane and the attached central stalk. The central stalk extends up about 45 A from the membrane surface and then penetrates into the alpha3beta3 subcomplex along its central axis. The mitochondrial peripheral stalk is an assembly of single copies of the oligomycin sensitivity conferral protein (the OSCP) and subunits b, d and F6. In the F-ATPase in Escherichia coli, its composition is simpler, and it consists of a single copy of the delta-subunit with two copies of subunit b. In some bacteria and in chloroplasts, the two copies of subunit b are replaced by single copies of the related proteins b and b' (known as subunits I and II in chloroplasts). As summarized in this review, considerable progress has been made towards establishing the structure and biophysical properties of the peripheral stalk in both the mitochondrial and bacterial enzymes. However, key issues are unresolved, and so our understanding of the role of the peripheral stalk and the mechanism of synthesis of ATP are incomplete.

Aging-induced alterations in gene transcripts and functional activity of mitochondrial oxidative phosphorylation complexes in the heart

“…Complex V is composed of two linked multi-subunit complexes, F 0 , the integral membrane-spanning component comprising the proton channel and F 1 , the catalytic portion of mitochondrial ATP synthase linked by a central and peripheral stalk (Carbajo et al, 2005;Walker and Dickson, 2006). We found that 9 of the 21 genes that code for subunits of complex V were downregulated in aged hearts (Fig.…”

“…Mitochondrial F 0 F 1 ATP synthase (Complex V) catalyzes ATP synthesis, utilizing the electrochemical gradient generated by proton efflux across the inner membrane during electron transfer (Walker and Dickson, 2006). Complex V is composed of two linked multi-subunit complexes, F 0 , the integral membrane-spanning component comprising the proton channel and F 1 , the catalytic portion of mitochondrial ATP synthase linked by a central and peripheral stalk (Carbajo et al, 2005;Walker and Dickson, 2006).…”

Detection of Alternative Splice Variants at the Proteome Level in Aspergillus flavus

“…43 F1 is the catalytic domain made of subunits. The mitochondrial F1 ATPase subunit alpha gene is conserved in Eukaryota including human, mouse, rat, chicken, fruit fly, worm, yeast, and plant.…”

Mechanism of inhibition of bovine F 1 -ATPase by resveratrol and related polyphenols

“…The ATP synthase is a multisubunit assembly found in the inner membrane of the organelle. It is composed of the F 1 catalytic domain (subunit composition ␣ 3 ␤ 3 ␥ 1 ␦ 1 1 ) attached by central (16) and peripheral stalks (17,18) to a membrane-embedded proton-translocating domain known as F o (19)(20)(21). The synthesis of ATP from ADP and phosphate is coupled by a mechanical rotary mechanism to a transmembrane proton-motive force generated by oxidative metabolism.…”