1P9R

Crystal Structure of Vibrio cholerae putative NTPase EpsE

Summary for 1P9R

• Entry DOI: 10.2210/pdb1p9r/pdb
• Related: 1P9R
• Descriptor: General secretion pathway protein E, ZINC ION, CHLORIDE ION, ... (4 entities in total)
• Functional Keywords: bacterial type ii secretion system cytoplasmic protein - gspe, putative atpase/ atp binding protein, metalloprotein (metal-cys4 site), protein transport
• Biological source: Vibrio cholerae
• Cellular location: Cytoplasm (Probable): P37093
• Total number of polymer chains: 1
• Total formula weight: 47219.77

Authors

Robien, M.A.,Krumm, B.E.,Sandkvist, M.,Hol, W.G.J. (deposition date: 2003-05-12, release date: 2003-10-14, Last modification date: 2024-11-06)

Primary citation

Robien, M.A.,Krumm, B.E.,Sandkvist, M.,Hol, W.G.J.
Crystal structure of the extracellular protein secretion NTPase EpsE of Vibrio cholerae
J.Mol.Biol., 333:657-674, 2003

PubMed Abstract: Type II secretion systems consist of an assembly of 12-15 Gsp proteins responsible for transporting a variety of virulence factors across the outer membrane in several pathogenic bacteria. In Vibrio cholerae, the major virulence factor cholera toxin is secreted by the Eps Type II secretion apparatus consisting of 14 Eps proteins. One of these, EpsE, is a cytoplasmic putative NTPase essential for the functioning of the Eps system and member of the GspE subfamily of Type II secretion ATPases. The crystal structure of a truncated form of EpsE in nucleotide-liganded and unliganded state has been determined, and reveals a two-domain architecture with the four characteristic sequence "boxes" of the GspE subfamily clustering around the nucleotide-binding site of the C-domain. This domain contains two C-terminal subdomains not reported before in this superfamily of NTPases. One of these subdomains contains a four-cysteine motif that appears to be involved in metal binding as revealed by anomalous difference density. The EpsE subunits form a right-handed helical arrangement in the crystal with extensive and conserved contacts between the C and N domains of neighboring subunits. Combining the most conserved interface with the quaternary structure of the C domain in a distant homolog, a hexameric model for EpsE is proposed which may reflect the assembly of this critical protein in the Type II secretion system. The nucleotide ligand contacts both domains in this model. The N2-domain-containing surface of the hexamer appears to be highly conserved in the GspE family and most likely faces the inner membrane interacting with other members of the Eps system.

PubMed: 14556751
DOI: 10.1016/j.jmb.2003.07.015

Experimental method

X-RAY DIFFRACTION (2.5 Å)