An IgG-like domain in the minor pilin GBS52 of Streptococcus agalactiae mediates lung epithelial cell adhesion.

摘要: Summary Streptococcus agalactiae is the leading cause of neonatal pneumonia, sepsis, and meningitis. The pathogen assembles heterotrimeric pilus structures on its surface; however, their function in pathogenesis poorly understood. We report here crystal structure pilin GBS52, which reveals two IgG-like fold domains, N1 N2. Each domain comprised seven antiparallel β strands, an arrangement similar to observed Staphylococcus aureus adhesin Cna. Consistent with role as adhesin, deletion gbs52 gene significantly reduces bacterial adherence pulmonary epithelial cells. Moreover, latex beads linked the GBS52 protein adhere but not many other cells; binding former specifically inhibited by antibodies against GBS52. Nonetheless, substantial is only N2 domain-conjugated beads. This study presents a Gram-positive that utilizes distinct IgG variant mediate specific tissue.