6BBT

Structure of the major pilin protein (T-13) from Streptococcus pyogenes serotype GAS131465

Summary for 6BBT

• Entry DOI: 10.2210/pdb6bbt/pdb
• Descriptor: Major pilin backbone protein T-antigen, T13, GLYCEROL, CALCIUM ION, ... (5 entities in total)
• Functional Keywords: trypsin-resistant surface protein tee13, lancefield t-antigen, serotyping, pili, fimbriae proteins, streptococcus pyogenes, isopeptide bond., structural protein
• Biological source: Streptococcus pyogenes
• Total number of polymer chains: 2
• Total formula weight: 62385.24

Authors

Young, P.G.,Baker, E.N.,Moreland, N.J. (deposition date: 2017-10-19, release date: 2018-10-24, Last modification date: 2024-11-06)

Primary citation

Young, P.G.,Raynes, J.M.,Loh, J.M.,Proft, T.,Baker, E.N.,Moreland, N.J.
Group AStreptococcusT Antigens Have a Highly Conserved Structure Concealed under a Heterogeneous Surface That Has Implications for Vaccine Design.
Infect.Immun., 87:-, 2019

PubMed Abstract: Group A (GAS) () is an important human pathogen associated with significant global morbidity and mortality for which there is no safe and efficacious vaccine. The T antigen, a protein that polymerizes to form the backbone of the GAS pilus structure, is a potential vaccine candidate. Previous surveys of the gene, which encodes the T antigen, have identified 21 different types and subtypes such that any T antigen-based vaccine must be multivalent and carefully designed to provide broad strain coverage. In this study, the crystal structures of three two-domain T antigens (T3.2, T13, and T18.1) were determined and found to have remarkable structural similarity to the previously reported T1 antigen, despite moderate overall sequence similarity. This has enabled reliable modeling of all major two-domain T antigens to reveal that T antigen sequence variation is distributed along the full length of the protein and shields a highly conserved core. Immunoassays performed with sera from immunized animals and commercial T-typing sera identified a significant cross-reactive antibody response between T18.1, T18.2, T3.2, and T13. The existence of shared epitopes between T antigens, combined with the remarkably conserved structure and high level of surface sequence divergence, has important implications for the design of multivalent T antigen-based vaccines.

PubMed: 30936156
DOI: 10.1128/IAI.00205-19

Experimental method

X-RAY DIFFRACTION (1.9 Å)