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Movies Kinesin & AMP-PNP [AVI format] [QuickTime format] This movie shows an experiment from: "Release of Isolated Single Kinesin Molecules from Microtubules." Yuliya Vugmeyster, Elise Berliner, and Jeff Gelles (1998) Biochemistry 37, pp. 747 -757. [abstract] [full text*] *Available only if you or your institution subscribe to the electronic edition of the journal. This movie was made by differential interference contrast video light microscopy. In this experiment, we see a single molecule of the biotinated kinesin derivative K448-BIO moving along a microtubule (the faint, nearly vertical line in the background).  The kinesin molecule is labeled with a 100 nm, streptavidin conjugated polystyrene bead to render it visible in the microscope.  The solution contains 1 mM ATP, kinesin's substrate, together with 1 mM AMP-PNP, an ATP analog that is a kinesin inhibitor.  In this experiment, it is possible to detect the binding of AMP-PNP to the single kinesin molecule moving the bead, because such inhibitor binding results in a detectable pause in the movement of the kinesin-bead conjugate.  When AMP-PNP is subsequently released, movement is resumed.  Such single-molecule experiments permit us to elucidate enzyme mechanisms and measure the kinetics of single reaction steps under normal, steady-state turnover conditions.