Capsular polysaccharide type 5 (CP5)

Capsular polysaccharide type 5 (CP5) is a specific extracellular polysaccharide capsule produced by certain strains of Staphylococcus aureus. It is one of the two predominant capsule types, the other being type 8, found in clinical S. aureus isolates[8][7]. CP5 consists of repeating trisaccharide units containing N-acetylmannosaminuronic acid, N-acetyl-L-fucosamine, and N-acetyl-D-fucosamine, with partial O-acetylation[1][3]. The capsule plays a major role as a virulence factor by protecting S. aureus from host immune responses, especially by inhibiting phagocytosis by neutrophils and macrophages, thus promoting bacterial persistence during infection[7][2][9]. Its expression is associated with increased virulence and is subject to regulation by environmental and genetic factors[5][4]. Due to its key role in immune evasion, CP5 has been explored as an antigen for vaccine development to induce protective immunity against S. aureus infections[8][7]. CP5 itself is not an enzyme, receptor, or transporter, but rather a carbohydrate structure serving as a target for antibodies and vaccines.

Other names

Staphylococcus aureus type 5 capsular polysaccharideS. aureus CP5Type 5 capsule

Induction of specific antibody response to facilitate opsonophagocytic killing\nNeutralization of antiphagocytic properties