ATP synthase peripheral stalk subunit b, mitochondrial (ATP5PB)

ATP synthase peripheral stalk subunit b, mitochondrial (ATP5PB), is a structural component of the mitochondrial ATP synthase complex. It is part of the peripheral stalk (the stator), which physically connects the catalytic F₁ head to the membrane-embedded F₀ domain and prevents the rotation of the F₁ sector with the central rotor during ATP synthesis. Subunit b ensures the integrity and the proper functioning of the ATP synthase holoenzyme, facilitating the conversion of the proton motive force into chemical energy (ATP) by maintaining the structural and mechanical coupling essential for the rotary catalytic mechanism[2][3][4]. Dysfunction or mutation in ATP5PB can impair mitochondrial ATP production and is implicated in a range of mitochondrial pathologies and energy-related diseases. The subunit is nuclear-encoded and imported into mitochondria to integrate with other ATP synthase subunits into the inner mitochondrial membrane[2].

Other names

ATP5PBATP synthase peripheral stalk-membrane subunit bATPase subunit bATP synthase F(0) complex subunit B1, mitochondrialATP synthase proton-transporting mitochondrial F(0) complex subunit B1ATP synthase subunit bATP5F1ATP synthase B chain, mitochondrialPIG47cell proliferation-inducing protein 47

Inhibitors such as oligomycin bind the F₀ domain (where subunit b is present), blocking proton translocation, which prevents ATP synthesis and affects cell viability[4].