3URM

Crystal structure of the periplasmic sugar binding protein ChvE

Summary for 3URM

• Entry DOI: 10.2210/pdb3urm/pdb
• Related: 3UUG
• Descriptor: Multiple sugar-binding periplasmic receptor ChvE, beta-D-galactopyranose (3 entities in total)
• Functional Keywords: periplasmic binding protein, sugar-binding protein, sugar, periplasmic, sugar binding protein
• Biological source: Agrobacterium tumefaciens
• Cellular location: Periplasm: P25548
• Total number of polymer chains: 2
• Total formula weight: 72097.17

Authors

Hu, X.,Zhao, J.,Binns, A.,Degrado, W. (deposition date: 2011-11-22, release date: 2012-11-28, Last modification date: 2023-09-13)

Primary citation

Hu, X.,Zhao, J.,Degrado, W.F.,Binns, A.N.
Agrobacterium tumefaciens recognizes its host environment using ChvE to bind diverse plant sugars as virulence signals.
Proc.Natl.Acad.Sci.USA, 110:678-683, 2013

PubMed Abstract: Agrobacterium tumefaciens is a broad host range plant pathogen that combinatorially recognizes diverse host molecules including phenolics, low pH, and aldose monosaccharides to activate its pathogenic pathways. Chromosomal virulence gene E (chvE) encodes a periplasmic-binding protein that binds several neutral sugars and sugar acids, and subsequently interacts with the VirA/VirG regulatory system to stimulate virulence (vir) gene expression. Here, a combination of genetics, X-ray crystallography, and isothermal calorimetry reveals how ChvE binds the different monosaccharides and also shows that binding of sugar acids is pH dependent. Moreover, the potency of a sugar for vir gene expression is modulated by a transport system that also relies on ChvE. These two circuits tune the overall system to respond to sugar concentrations encountered in vivo. Finally, using chvE mutants with restricted sugar specificities, we show that there is host variation in regard to the types of sugars that are limiting for vir induction.

PubMed: 23267119
DOI: 10.1073/pnas.1215033110

Experimental method

X-RAY DIFFRACTION (1.801 Å)