what is a function of a bacterium's capsule?

A function of a bacterium's capsule is to protect the bacterium from phagocytosis by immune cells, such as macrophages, thereby helping the bacterium evade the host immune system. Additionally, the capsule prevents desiccation (drying out) by retaining water, facilitates adhesion to surfaces and other bacteria, and can shield the bacterium from toxins and viral attacks. This protective layer also acts as a virulence factor, enhancing the bacterium's ability to cause disease.