A Molecular Machine in Action

Researchers at the Lawrence Berkeley National Laboratory have used advanced imaging techniques to solve the structure of one of nature’s most important molecular machines. A clearer picture of this motor-like protein, which spins along strands of bacterial messenger RNA to read and translate it into proteins, may help pharmaceutical researchers develop new antibiotics. The researchers studied a version of the protein called Rho from E. coli bacteria. This type of protein, called a transcription factor, is also important in human development and disease.

In the video below, Rho, which is shaped like a hexagon with a hole in the center, is shown in cross section as it walks along the RNA strand, shown in orange. Rho spirals in such a way that it can only move in one direction along the RNA strand, which is crucial to making proteins properly.

In order to get a better picture of Rho, the Berkeley researchers used the lab’s Advanced Light Source, which accelerates electrons to very high energies in order to create some of the brightest x-rays in the world. Using these x-rays, they were able to see a part of Rho’s structure that was previously not very well understood.