PDBsum entry: 1klx

Hydrolase

PDB id: 1klx

Contents

Protein chain

133 a.a. *

Waters ×189

* Residue conservation analysis

PDB id:

1klx

Name:

Hydrolase

Title:

Helicobacter pylori cysteine rich protein b (hcpb)

Structure:

Cysteine rich protein b. Chain: a. Engineered: yes

Source:

Helicobacter pylori. Organism_taxid: 210. Gene: hp0336. Expressed in: escherichia coli bl21(de3). Expression_system_taxid: 469008.

Biol. unit:

Dimer (from PQS)

Resolution:

1.95Å R-factor: 0.192 R-free: 0.238

Authors:

L.Luethy,M.G.Gruetter,P.R.E.Mittl

Key ref:

L.Luthy et al. (2002). The crystal structure of Helicobacter pylori cysteine-rich protein B reveals a novel fold for a penicillin-binding protein. J Biol Chem, 277, 10187-10193. PubMed id: 11777911 DOI: 10.1074/jbc.M108993200

Date:

13-Dec-01 Release date: 11-Sep-02

Protein chain

O25103  (HCPB_HELPY) -  Beta-lactamase hcpB

Seq: 138 a.a.

Struc: 133 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 

• Biological process: response to antibiotic (1 term)
• Biochemical function: binding (3 terms)

DOI no: 10.1074/jbc.M108993200

J Biol Chem 277:10187-10193 (2002)

PubMed id: 11777911

The crystal structure of Helicobacter pylori cysteine-rich protein B reveals a novel fold for a penicillin-binding protein.

L.Luthy, M.G.Grutter, P.R.Mittl.

ABSTRACT

Colonization of the gastric mucosa with the spiral-shaped Gram-negative proteobacterium Helicobacter pylori is probably the most common chronic infection in humans. The genomes of H. pylori strains J99 and 26695 have been completely sequenced. Functional and three-dimensional structural information is available for less than one third of all open reading frames. We investigated the function and three-dimensional structure of a member from a family of cysteine-rich hypothetical proteins that are unique to H. pylori and Campylobacter jejuni. The structure of H. pylori cysteine-rich protein (Hcp) B possesses a modular architecture consisting of four alpha/alpha-motifs that are cross-linked by disulfide bridges. The Hcp repeat is similar to the tetratricopeptide repeat, which is frequently found in protein/protein interactions. In contrast to the tetratricopeptide repeat, the Hcp repeat is 36 amino acids long. HcpB is capable of binding and hydrolyzing 6-amino penicillinic acid and 7-amino cephalosporanic acid derivatives. The HcpB fold is distinct from the fold of any known penicillin-binding protein, indicating that the Hcp proteins comprise a new family of penicillin-binding proteins. The putative penicillin binding site is located in an amphipathic groove on the concave side of the molecule.

Selected figure(s)

Figure 3.
Fig. 3. a, CD spectrum of refolded HcpB. b, ellipticity at a wavelength of 222 nm as a function of GdmHCl concentration. mdeg, millidegrees.

Figure 4.
Fig. 4. a, water molecules and 2Fo-Fc electron density (contour level of 1.3 ) in the putative ligand binding site. The density is explained by 11 water molecules. N-acetylmuramic acid was modeled into the electron density of the water molecule cluster. b, modeled N-acetylmuramic acid/HcpB complex. The ligand could form hydrogen bonds with residues in the loops between helices A and B of motifs 1, 2, and 3.

The above figures are reprinted by permission from the ASBMB: J Biol Chem (2002, 277, 10187-10193) copyright 2002.

Figures were selected by an automated process.