Recent advances in single-molecule labeling and detection techniques allow high-resolution imaging of the motion of single molecules. Molecular motors are biological machines that convert chemical energy into mechanical work. Myosin Va (MyoVa) is a well-characterized processive molecular motor, essential for cargo transport in living organisms. Quantum dots (Qdots) are fluorescent semiconductor nanocrystals that are extremely useful for single-molecule studies in biological sciences. High-resolution video microscopy and single-particle tracking of a Qdot-labeled MyoVa motor molecule allow the detection of individual steps in vitro and in live cells.
