carboxysome

Carboxysomes are small compartments inside photosynthetic bacteria where the machinery for capturing carbon dioxide is concentrated. You can see carboxysomes and their characteristic virus-like shape when you look at slices of these bacteria under an electron microscope: Until recently, no one had looked at carboxysomes under the microscope in cells that were still alive. My labmates Dave and Bruno developed a way to label carboxysomes with fluorescent proteins and track them under a microscope as the cells grow, and their amazing paper in Science details some of the fascinating systems they…

Animal cells are made up of many smaller membrane-bound compartments called organelles that perform highly specialized functions necessary for life. Incredibly, several of these organelles have been shown to be evolutionarily related to free-living bacteria, captured and incorporated inside a larger cell billions of years ago in a complex mutually beneficial relationship, known as endosymbiosis (a partnership between two species where one of the species is inside the other). The mitochondria that power our cells, generating energy by breaking down sugars are in fact relatives of regular old…