ATP synthase structure

Dimroth P, Ballmoos Cv, Meier T, Kaim G. 2003. Electrical power fuels rotary ATP synthase. Structure 11 1469. 

Muller, V., and Gruber, G. (2003). ATP synthases Structure, function and evolution of unique energy converters. Cell. Mol. Life Sci. 60, 474-494. 

Vogel, P. D.. (2000) Insights into ATP synthase structure and function using affinity and site-specific spin labeling, Journal of Bioenergetics and Biomembranes 32, 413-421. 

FIGURE 21.25 A model of the Fj and Fg components of the ATP synthase, a rotating molecnlar motor. The a, b, a, /3, and 8 snbnnits constitute the stator of the motor, and the c, y, and e subunits form the rotor. Flow of protons through the structure turns the rotor and drives the cycle of conformational changes in a and fi that synthesize ATP. 

FIGURE 21.31 Structures of several uiicouplers, molecules that dissipate the proton gradient across the inner mitochondrial membrane and thereby destroy the tight coupling between electron transport and the ATP synthase reaction. 

Deckers-Hebestreit, G. and Altendorf, K. (1996). The FoFi-type ATP synthases of bacteria structure and function of the F0 complex, Ann. Rev. Microbiol., 50, 791-824. 

Figure 5.18 Structure of ATP synthase. (From Berg et al., 2002. Reproduced with permission from W.H. Freeman and Co.)...

Das A, Ljungdahl LG. 1997. Composition and primary structure of the FiFq ATP synthase from the obhgately anaerobic bacterium Clostridium thermoaceticum. J Bacteriol 179 3746-55. 

The concept of rotational catalysis by ATP synthase is based on (a) P and 0 exchange rate data attesting to strong cooperativity with sequential participation of several catalytic sites (b) Pi and ATP 0-isotopomer distributions indicating that all catalytic sites exhibit identical catalysis and (c) that catalysis is strongly influenced by the y-subunit whose primary structure was not likely to account for spatially similar interactions with the /3-subunits . The model was found to be compatible with the 2.8 A resolution structure of bovine heart mitochondrial Fi-ATPase. ... 

ATP synthesis takes place by conformational changes at the catalytic binding sites. Recent structural [21, 27], biochemical [13, 28, 31], spectroscopic [32, 33] and microscopic [34, 35] studies indicate that these conformational changes arise from rotation of the y- subunit in a static barrel of agPj subunits in ATP synthase, making it the world s smallest molecular machine with a rotor radius of 1 nm (Fig. 1). 

In the Walker crystal structure of Fj-ATPase, the three non-catalytic a sites are liganded with the non-hydrolyzable ATP analog MgAMP-PNP. In contrast, the three catalytic (3 sites possess different conformations. One of the catalytic sites in the structure binds the analog MgAMP-PNP and is designated as Pjp another site binds MgADP and is denoted by (3dp, while the third site is empty and distorted and is called (3e [21]. In further contrast, the nucleotide-free subcomplex of ATP synthase is a symmetric trimer [36]. 

FIGURE 11-39 Structure of the F F] ATPase/ATP synthase. F-type ATPases have a peripheral domain, F, consisting of three cr subunits, three j3 subunits, one S subunit (purple), and a central shaft (the y subunit, green). The integral portion of F-type ATPases, F0 (yellow), has multiple copies of c, one a, and two b subunits. F0 provides a transmembrane channel through which about four protons are pumped (red arrows) for each ATP hydrolyzed on the j3 subunits of F,. The remarkable mechanism by which these two events are coupled is described in detail in Chapter 19. It involves rotation of F0 relative to F, (black arrow). The structures of V0Vi and AoA, are essentially similar to that of F0F, and the mechanisms are probably similar, too. 

For the continued synthesis of ATP, the enzyme must cycle between a form that binds ATP very tightly and a form that releases ATP. Chemical and crystallographic studies of the ATP synthase have revealed the structural basis for this alternation in function. 

Detailed review of the structures that underlie proton-driven rotary motion of ATP synthase and bacterial flagella. 

An advanced review of kinetic, structural, and biochemical evidence for the ATP synthase mechanism. 

We now recognize not only that these complexes are discrete structural units but also that they are functional units. Complete X-ray crystallographic structures are available for complexes III and IV and for much of the ATP synthase complex. As is indicated in Fig. 18-5, complexes I - IV are linked by two soluble electron carriers, ubiquinone and cytochrome c. 

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