Kinesin's moonwalk.
Kinesin-1 is a single-molecule walking machine, driven by ATP turnover. Recent optical trapping experiments show that pulling backwards on a walking kinesin-1 molecule causes the mechanical walking action to reverse, while the coupled chemical cycle of ATP turnover continues, apparently, to run forwards -- kinesin can moonwalk. Individual forward- and back-steps are fast, and each appears to be a single event, complete in a few tens of microseconds, with no substeps. Between steps, kinesin pauses, waiting for the next ATP to arrive. Several lines of evidence indicate that during these between-step dwells, only one of the two heads is strongly attached to the microtubule. The position of the other head during the dwells is less certain, and more controversial.
Carter
Nicholas J
NJ
Molecular Motors Group, Marie Curie Research Institute, The Chart, Oxted, Surrey, RH8 0TE UK.
Cross
Robert A
RA
D000255:Adenosine Triphosphate / Q000737:chemistry; D016547:Kinesins / Q000737:chemistry* / Q000378:metabolism; D008870:Microtubules / Q000378:metabolism; D008954:Models, Biological; D020409:Molecular Motor Proteins / Q000378:metabolism*; D009068:Movement; D011487:Protein Conformation; D013997:Time Factors
D020409:Molecular Motor Proteins; D000255:Adenosine Triphosphate; D016547:Kinesins