CsbD adhesin (CsbD)

CsbD adhesin is the **tip adhesin protein of the CS17 fimbriae**, a class 5 fimbrial structure produced by enterotoxigenic Escherichia coli (ETEC). It mediates the specific binding of bacteria to the host intestinal epithelia, facilitating colonization and infection. Structurally, CsbD consists of two main domains: a lectin (adhesin) domain with a putative receptor-binding site and a pilin domain that anchors the adhesin to the fimbrial shaft, closely resembling the CfaE adhesin of CFA/I fimbriae[1][2]. Mutational analyses indicate that most adaptive changes cluster around the predicted ligand-binding pocket of the lectin domain, emphasizing its role in host interaction and immune evasion[1]. As a critical ETEC colonization factor, CsbD is explored as a potential **vaccine antigen**, with its structural integrity (including β-strands in the pilin domain) contributing to vaccine solubility, stability, and immunogenicity[2]. There are currently no approved drugs targeting CsbD directly, but it is considered a relevant anti-adhesion vaccine candidate.

Other names

CS17 fimbrial adhesinCS17 tip adhesinEnterotoxigenic Escherichia coli CsbD

Inhibition of adhesion of pathogens to host cells (theoretical for anti-adhesin agents or vaccines); not a direct drug target currently