This is the second domain on the N-terminal region found on the alpha C protein (ACP). ACP is found in Streptococcus and acts as an invasin which plays a role in the internalisation and translocation of the organism across human epithelial surfaces [ ...
This is the second domain on the N-terminal region found on the alpha C protein (ACP). ACP is found in Streptococcus and acts as an invasin which plays a role in the internalisation and translocation of the organism across human epithelial surfaces [1]. Group B Streptococcus is the leading cause of diseases including bacterial pneumonia, sepsis and meningitis. ACP consists of an N-terminal domain (NtACP; 170 amino acids) followed by a variable number of tandem repeats (82 amino acids each) and a C-terminal domain (45 amino acids) containing an LPXTG peptidoglycan-anchoring motif. The NtACP, contains two structural domains, D1 and D2. D1, the more distal (amino-terminal) portion Pfam:PF08829 and consists of a beta sandwich with strong structural homology to fibronectin's integrin-binding region (FnIII10). This entry, D2 (connects distally to Domain 1 and proximally to the repeat region) [1] consists of three antiparallel alpha helix coils [2]. It is suggested that the GAG-binding region of ACP may extend from Domain 2 into the repeat region [3].
The region featured in this family is found repeated in a number of bacterial surface proteins, such as Rib (Swiss:P72362) and alpha (Swiss:Q02192). These are expressed by group B streptococci, and Rib is thought to confer protective immunity.