Bacterial Capsules

**Definition:** An envelope of loose gel surrounding a bacterial cell which is associated with the virulence of pathogenic bacteria. Some capsules have a well-defined border, whereas others form a slime layer that trails off into the medium. Most capsules consist of relatively simple polysaccharides but there are some bacteria whose capsules are made of polypeptides.

**Tree numbers:** - A20.186

**Synonyms:** - Bacterial Capsule - Capsule, Bacterial - Capsules, Bacterial