Staphylococcus aureus

Bacterial cells of Staphylococcus aureus, which is one of the causal agents of mastitis in dairy cows. Its large capsule protects the organism from attack by the cows immunological defenses. This image was taken at 50,000X magnification on a Transmission Electron Microscope of a heavy-metal coated replica of a freeze dried sample, (TEM) Plate #.9514.