Rotation of F_1-ATPase at extremely low ATP concentrations
نویسندگان
چکیده
منابع مشابه
Acceleration of the ATP-binding rate of F1-ATPase by forcible forward rotation.
F1-ATPase (F1) is a reversible ATP-driven rotary motor protein. When its rotary shaft is reversely rotated, F1 produces ATP against the chemical potential of ATP hydrolysis, suggesting that F1 modulates the rate constants and equilibriums of catalytic reaction steps depending on the rotary angle of the shaft. Although the chemomechanical coupling scheme of F1 has been determined, it is unclear ...
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We have analyzed the movement of single 22S dynein molecules from Tetrahymena cilia by using a nanometer measuring system equipped with optical tweezers. Statistical analysis proved that a single molecule of 22S dynein can move processively and develop force at low concentrations of ATP (<20 microM). The maximum force was approximately 4.7 pN, and the force-velocity curve was convex down. Durin...
متن کاملF1-ATPase, the C-terminal End of Subunit Is Not Required for ATP Hydrolysis-driven Rotation*
ATP hydrolysis by the isolated F1-ATPase drives the rotation of the central shaft, subunit , which is located within a hexagon formed by subunits ( )3. The C-terminal end of forms an -helix which properly fits into the “hydrophobic bearing” provided by loops of subunits and . This “bearing” is expected to be essential for the rotary function. We checked the importance of this contact region by ...
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F(1)-ATPase is an ATP-driven rotary molecular motor that synthesizes ATP when rotated in reverse. To elucidate the mechanism of ATP synthesis, we imaged binding and release of fluorescently labelled ADP and ATP while rotating the motor in either direction by magnets. Here we report the binding and release rates for each of the three catalytic sites for 360° of the rotary angle. We show that the...
متن کاملRotation of F1-ATPase: how an ATP-driven molecular machine may work.
F1-ATPase is a rotary motor made of a single protein molecule. Its rotation is driven by free energy obtained by ATP hydrolysis. In vivo, another motor, Fo, presumably rotates the F1 motor in the reverse direction, reversing also the chemical reaction in F1 to let it synthesize ATP. Here we attempt to answer two related questions, How is free energy obtained by ATP hydrolysis converted to the m...
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ژورنال
عنوان ژورنال: Seibutsu Butsuri
سال: 2003
ISSN: 0582-4052,1347-4219
DOI: 10.2142/biophys.43.s135_3