Axle-Less F 1 -ATPase Rotates in the Correct Direction
2008; American Association for the Advancement of Science; Volume: 319; Issue: 5865 Linguagem: Inglês
10.1126/science.1151343
ISSN1095-9203
AutoresShou Furuike, Mohammad Delawar Hossain, Yasushi Maki, Kengo Adachi, Toshiharu Suzuki, Ayako Kohori, Hiroyasu Itoh, Masasuke Yoshida, Kazuhiko Kinosita,
Tópico(s)Biochemical and Molecular Research
ResumoF1-adenosine triphosphatase (ATPase) is an ATP-driven rotary molecular motor in which the central gamma subunit rotates inside a cylinder made of three alpha and three beta subunits alternately arranged. The rotor shaft, an antiparallel alpha-helical coiled coil of the amino and carboxyl termini of the gamma subunit, deeply penetrates the central cavity of the stator cylinder. We truncated the shaft step by step until the remaining rotor head would be outside the cavity and simply sat on the concave entrance of the stator orifice. All truncation mutants rotated in the correct direction, implying torque generation, although the average rotary speeds were low and short mutants exhibited moments of irregular motion. Neither a fixed pivot nor a rigid axle was needed for rotation of F1-ATPase.
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