PDBsum entry: 1ouv

Hydrolase

PDB id: 1ouv

Contents

Protein chain

265 a.a. *

Waters ×175

* Residue conservation analysis

PDB id:

1ouv

Name:

Hydrolase

Title:

Helicobacter cysteine rich protein c (hcpc)

Structure:

Conserved hypothetical secreted protein. Chain: a. Synonym: helicobacter cysteine rich protein c, hcpc. Engineered: yes

Source:

Helicobacter pylori. Organism_taxid: 85962. Strain: 26695. Gene: hp1098. Expressed in: escherichia coli bl21(de3). Expression_system_taxid: 469008.

Biol. unit:

Dimer (from PQS)

Resolution:

2.00Å R-factor: 0.202 R-free: 0.249

Authors:

P.R.Mittl,L.Luethy

Key ref:

L.Lüthy et al. (2004). The crystal structure of Helicobacter cysteine-rich protein C at 2.0 A resolution: similar peptide-binding sites in TPR and SEL1-like repeat proteins. J Mol Biol, 340, 829-841. PubMed id: 15223324 DOI: 10.1016/j.jmb.2004.04.055

Date:

25-Mar-03 Release date: 30-Mar-04

Protein chain

O25728  (HCPC_HELPY) -  Putative beta-lactamase hcpC

Seq: 290 a.a.

Struc: 265 a.a.

Enzyme reactions

• Enzyme class: E.C.3.5.2.6 - Beta-lactamase.
• Pathway: Penicillin Biosynthesis and Metabolism
• Reaction: A beta-lactam + H₂O = a substituted beta-amino acid
• Cofactor: Zinc

 Gene Ontology (GO) functional annotation 

• Biochemical function: binding (2 terms)

DOI no: 10.1016/j.jmb.2004.04.055

J Mol Biol 340:829-841 (2004)

PubMed id: 15223324

The crystal structure of Helicobacter cysteine-rich protein C at 2.0 A resolution: similar peptide-binding sites in TPR and SEL1-like repeat proteins.

L.Lüthy, M.G.Grütter, P.R.Mittl.

ABSTRACT

Helicobacter pylori is a Gram-negative human pathogen that infects the gastric mucosa and causes an inflammatory process leading to gastritis, ulceration and cancer. Bacterial cell-surface and secreted proteins often play an important role in pathogen-host interactions and are thought to be selective mediators for the pathology of the infection. The Helicobacter cysteine-rich proteins (Hcp) represent a large family of secreted proteins that seem to be specific for microorganisms from the epsilon-subfamily of proteobacteria. Although significantly elevated levels of anti-Hcp antibodies were observed in many patients infected with H.pylori, details on the biological functions of Hcp proteins are sparse. Hcps belong to a large family of Sel1-like multi-repeat proteins. The crystal structure of HcpC was refined at 2.0 A resolution and revealed a super-helical topology composed of seven disulfide bridged alpha/alpha-repeats, an N-terminal capping helix and an extended C-terminal coil consisting of alternating hydrophobic and hydrophilic residues. In the crystal packing, the C-terminal coil interacts with the concave surface of a symmetry-related HcpC super-helix. A hydrophobic pocket and a cluster of negatively charged residues recognize the side-chains of Val290 and Lys287 from the C-terminal coil, respectively. The peptide nitrogen atom of His291 forms a short hydrogen bond with the side-chain of Asn66. The interactions seen in this crystal contact are strikingly similar to the peptide-binding modes of the Hsp70/Hsp90 organizing protein and the PEX5 receptor. The conservation of the peptide-binding mode suggests that HcpC might recognize its binding partner in a similar way.

Selected figure(s)

Figure 1.
Figure 1. (a) Stereo plot of HcpC in a ribbon representation. The N-terminal capping helix, helix A and helix B are shown in green, red and blue, respectively. The disulphide bridges are indicated. (b) Sketch of the HcpC super-helix. Helices A and B form a right-handed super-helix (emphasized in light and dark grey), which again winds around a central axis. (c) Molecular surface of HcpC. Red and blue areas indicate negative and positive charge density, respectively.

Figure 2.
Figure 2. (a) Stereo plot of the superposition of Hcp-repeats from HcpB[24.] and HcpC. The N-terminal, central and C-terminal repeats are shown in yellow, blue and red, respectively. (b) Stereo plot of HcpC residues 62-108. Side-chains of conserved residues are shown and the numbering refers to the position in the repeat. Hyphenated numbers refer to the previous repeat. (c) Alignment of repeats in HcpB and HcpC. Conserved residues are emphasized in black (short side-chain), blue (positively charged), green (cysteine residue) and magenta (hydrophobic side-chain). Residues that are involved in crystal contact I are underlined. At the top the consensus sequence for 80% of the family of SEL1-like proteins is indicated (taken from http://smart.embl-heidelberg.de/).[27.] Residues are abbreviated as follows: A, alanine; G, glycine; h, hydrophobic; l, isoleucine, valine or leucine; p, polar; s, small; t, turnlike; u, alanine, glycine or serine.

The above figures are reprinted by permission from Elsevier: J Mol Biol (2004, 340, 829-841) copyright 2004.

Figures were selected by an automated process.