6S5Y

Structure of tandemly arrayed consecutive Rib domains (Rib2R) from Group B Streptococcal species Streptococcus agalactiae

Summary for 6S5Y

• Entry DOI: 10.2210/pdb6s5y/pdb
• Descriptor: Group B streptococcal R4 surface protein (2 entities in total)
• Functional Keywords: rib domain, bacterial cell surface, immunoglobulin fold, profile-hmm, domain atrophy, structural protein
• Biological source: Streptococcus agalactiae
• Total number of polymer chains: 8
• Total formula weight: 135035.64

Authors

Whelan, F.,Griffiths, S.C.,Bateman, A.,Potts, J.R. (deposition date: 2019-07-02, release date: 2019-12-11, Last modification date: 2024-06-19)

Primary citation

Whelan, F.,Lafita, A.,Griffiths, S.C.,Cooper, R.E.M.,Whittingham, J.L.,Turkenburg, J.P.,Manfield, I.W.,St John, A.N.,Paci, E.,Bateman, A.,Potts, J.R.
Defining the remarkable structural malleability of a bacterial surface protein Rib domain implicated in infection.
Proc.Natl.Acad.Sci.USA, 116:26540-26548, 2019

PubMed Abstract: groups A and B cause serious infections, including early onset sepsis and meningitis in newborns. Rib domain-containing surface proteins are found associated with invasive strains and elicit protective immunity in animal models. Yet, despite their apparent importance in infection, the structure of the Rib domain was previously unknown. Structures of single Rib domains of differing length reveal a rare case of domain atrophy through deletion of 2 core antiparallel strands, resulting in the loss of an entire sheet of the β-sandwich from an immunoglobulin-like fold. Previously, observed variation in the number of Rib domains within these bacterial cell wall-attached proteins has been suggested as a mechanism of immune evasion. Here, the structure of tandem domains, combined with molecular dynamics simulations and small angle X-ray scattering, suggests that variability in Rib domain number would result in differential projection of an N-terminal host-colonization domain from the bacterial surface. The identification of 2 further structures where the typical B-D-E immunoglobulin β-sheet is replaced with an α-helix further confirms the extensive structural malleability of the Rib domain.

PubMed: 31818940
DOI: 10.1073/pnas.1911776116

Experimental method

X-RAY DIFFRACTION (2.3 Å)