Michael G. Rossmann of Purdue University and his colleagues studied the T4 virus, which alters its shape as it prepares to strike. The researchers obtained the highest-resolution images yet of the process of T4 attacking an E. coli bacterium using an electron microscope and strung them together into a film. In particular, the pictures focus on a part of the virus known as the baseplate, which is made up of 16 kinds of protein molecules. "Instead of a still photo of the baseplate, we now have a movie of it opening," Rossmann explains. "A better understanding of the infection process is a step forward for fundamental science, but it also could allow scientists to alter the baseplate so that the virus could infect cells other than E. coli. T4 might then be used to deliver beneficial genes to damaged or infected human tissue."
Writing in the latest issue of the journal Cell, the researchers describe the intricate movements of the baseplate's proteins. "Viruses are among the tiniest of biological entities, Rossman says, "yet nature has designed them to perform very complicated tasks. The team hopes to get an even better close-up of T4's machinery in the future.