Molecular Motors, Beauty in Complexity

摘要

Among the most fascinating enzymes are the molecular motors, which exquisitely couple adenosine tri-phosphate (ATP) hydrolysis to directional mechanical motion. They power the movement of intracellular vesicles, chromosomes, and messenger RNA-protein complexes through the cytoplasm of nearly all eukary-otic cells, using actin filaments and microtu-bules as their tracks. A prominent theme in these motors is allostery, or communications that occur across the enzyme at several nanometer distances. Chemical events occurring in the motor's active site, for instance, are coordinated with tight binding of the motor to the track along which it moves, and then its subsequent release, and with mechanical elements that amplify small movements occurring near the active site. In the 1980s,