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Pseudomonas bacteria infect a thale cress

The scanning electron microscope images show rod-shaped Pseudomonas bacteria located around a stoma on the leaf of a thale cress (Arabidopsis thaliana). The plant uses stomata to take up carbon dioxide for photosynthesis. The bacteria release messenger substances that cause the plant to open the stomata further. This allows the bacteria to enter the inside of the leaf more easily.