As inventors and factory owners learned during the Industrial Revolution, the best way to manufacture a lot of products is with an assembly line that follows a set of precisely organized steps employing many copies of identical and interchangeable parts. Some viruses are among life’s original mass producers: They use sophisticated organization principles to turn bacterial cells into virus particle factories.
Scientists at the University of California, San Diego, and the University of California, San Francisco, used cutting-edge techniques to watch a bacteria-infecting virus (bacteriophage) set up its particle-making factory inside a host cell.
The image above shows this happening inside a Pseudomonas chlororaphis, a soil-borne bacterium that protects plants against fungal pathogens. The virus builds a compartment (red, rough circle surrounding the center) that helps organize an assembly line for making copies of itself. The compartment looks like a cell nucleus, which bacteria do not have, and it functions like a nucleus by keeping activities that directly involve DNA separate from other cellular functions. Continue reading