Structural Insights of Shigella Translocator IpaB and Its Chaperone IpgC in Solution - Institut Pasteur Access content directly
Journal Articles Frontiers in Cellular and Infection Microbiology Year : 2021

Structural Insights of Shigella Translocator IpaB and Its Chaperone IpgC in Solution

Abstract

Bacterial Type III Secretion Systems (T3SSs) are specialized multicomponent nanomachines that mediate the transport of proteins either to extracellular locations or deliver Type III Secretion effectors directly into eukaryotic host cell cytoplasm. Shigella, the causing agent of bacillary dysentery or shigellosis, bears a set of T3SS proteins termed translocators that form a pore in the host cell membrane. IpaB, the major translocator of the system, is a key factor in promoting Shigella pathogenicity. Prior to secretion, IpaB is maintained inside the bacterial cytoplasm in a secretion competent folding state thanks to its cognate chaperone IpgC. IpgC couples T3SS activation to transcription of effector genes through its binding to MxiE, probably after the delivery of IpaB to the secretion export gate. Small Angle X-ray Scattering experiments and modeling reveal that IpgC is found in different oligomeric states in solution, as it forms a stable heterodimer with fulllength IpaB in contrast to an aggregation-prone homodimer in the absence of the translocator. These results support a stoichiometry of interaction 1:1 in the IpgC/IpaB complex and the multi-functional nature of IpgC under different T3SS states.
Fichier principal
Vignette du fichier
fcimb-11-673122(1).pdf (35.87 Mo) Télécharger le fichier
Origin Publication funded by an institution

Dates and versions

pasteur-03217402 , version 1 (04-05-2021)

Licence

Identifiers

Cite

Mariana L Ferrari, Spyridoula N Charova, Philippe J Sansonetti, Efstratios Mylonas, Anastasia Gazi. Structural Insights of Shigella Translocator IpaB and Its Chaperone IpgC in Solution. Frontiers in Cellular and Infection Microbiology, 2021, 11, pp.673122. ⟨10.3389/fcimb.2021.673122⟩. ⟨pasteur-03217402⟩
60 View
30 Download

Altmetric

Share

Gmail Mastodon Facebook X LinkedIn More