N-terminal domain of alpha-like protein (Alp-N)

The N-terminal domains of alpha-like proteins (Alp) are critical surface-exposed components of Streptococcus agalactiae, also known as Group B Streptococcus (GBS) [PMID: 26169271]. This protein family includes several members such as the Alpha C protein, Rib, Alp1, Alp2, Alp3, and Alp4, which are characterized by a conserved N-terminal region and a variable number of tandem repeats [PMID: 15103027]. These domains play a vital role in bacterial pathogenesis by mediating adhesion to host epithelial cells and facilitating invasion into deeper tissues, thereby contributing to the development of neonatal sepsis, meningitis, and pneumonia [PMID: 23460517]. Because these N-terminal regions are highly immunogenic and relatively conserved across different GBS strains, they are primary targets for the development of protein-based vaccines [PMID: 31151811]. Therapeutic strategies, such as the GBS-NN and GBS-NN2 vaccine candidates, utilize recombinant N-terminal domains to elicit opsonophagocytic antibodies [PMID: 27510874]. These antibodies enhance bacterial clearance by the host immune system and provide broad protection against GBS infections, regardless of the capsular serotype [PMID: 26169271].

Other names

Alpha-like protein N-terminal domainAlp family N-terminal domainGBS surface protein N-terminal domainAlpha C protein N-terminal domainRib protein N-terminal domain

Vaccine-mediated induction of opsonophagocytic antibodies that bind to the N-terminal domains, blocking bacterial attachment to host cells and facilitating immune-mediated clearance [PMID: 31151811].