Capsule [cracked] — Poly D Glutamic Acid

The PDA capsule is encoded on the (60–95 kb) in B. anthracis .

The is a unique polypeptide-based capsule found primarily in Bacillus anthracis (the causative agent of anthrax). Unlike most bacterial capsules composed of polysaccharides (e.g., in Streptococcus pneumoniae or Haemophilus influenzae ), the PDA capsule is made of amino acids. poly d glutamic acid capsule

The operon capBCAD drives expression under appropriate conditions (e.g., host environment, CO₂/bicarbonate). The PDA capsule is encoded on the (60–95 kb) in B

The capsule is anchored to the bacterial surface by a specific enzyme, typically a Phagocytic cells (such as macrophages and neutrophils) are

The primary function of the capsule is to protect the bacteria from phagocytosis. Phagocytic cells (such as macrophages and neutrophils) are the body's first line of defense; they engulf and destroy foreign invaders. The thick, tenacious PGA capsule makes the B. anthracis cell surface slippery and highly resistant to being engulfed by these immune cells.