4Q1Q

Crystal structure of TibC-catalyzed hyper-glycosylated TibA55-350 fragment

Summary for 4Q1Q

• Entry DOI: 10.2210/pdb4q1q/pdb
• Descriptor: Adhesin/invasin TibA autotransporter, D-glycero-alpha-D-manno-heptopyranose (3 entities in total)
• Functional Keywords: beta-helix, adhesion, cell adhesion
• Biological source: Escherichia coli
• Total number of polymer chains: 2
• Total formula weight: 75057.14

Authors

Yao, Q.,Lu, Q.,Shao, F. (deposition date: 2014-04-04, release date: 2014-09-17, Last modification date: 2024-04-03)

Primary citation

Lu, Q.,Yao, Q.,Xu, Y.,Li, L.,Li, S.,Liu, Y.,Gao, W.,Niu, M.,Sharon, M.,Ben-Nissan, G.,Zamyatina, A.,Liu, X.,Chen, S.,Shao, F.
An iron-containing dodecameric heptosyltransferase family modifies bacterial autotransporters in pathogenesis
Cell Host Microbe, 16:351-363, 2014

PubMed Abstract: Autotransporters deliver virulence factors to the bacterial surface by translocating an effector passenger domain through a membrane-anchored barrel structure. Although passenger domains are diverse, those found in enteric bacteria autotransporters, including AIDA-I in diffusely adhering Escherichia coli (DAEC) and TibA in enterotoxigenic E. coli, are commonly glycosylated. We show that AIDA-I is heptosylated within the bacterial cytoplasm by autotransporter adhesin heptosyltransferase (AAH) and its paralogue AAH2. AIDA-I heptosylation determines DAEC adhesion to host cells. AAH/AAH2 define a bacterial autotransporter heptosyltransferase (BAHT) family that contains ferric ion and adopts a dodecamer assembly. Structural analyses of the heptosylated TibA passenger domain reveal 35 heptose conjugates forming patterned and solenoid-like arrays on the surface of a β helix. Additionally, CARC, the AIDA-like autotransporter from Citrobacter rodentium, is essential for colonization in mice and requires heptosylation by its cognate BAHT. Our study establishes a bacterial glycosylation system that regulates virulence and is essential for pathogenesis.

PubMed: 25211077
DOI: 10.1016/j.chom.2014.08.008

Experimental method

X-RAY DIFFRACTION (2.11 Å)