PDBsum entry: 2bib

Hydrolase

PDB id: 2bib

Contents

Protein chain

541 a.a. *

Ligands

_PC

BTB ×7

Metals

_CA ×2

_ZN ×2

Waters ×432

* Residue conservation analysis

PDB id:

2bib

Name:

Hydrolase

Title:

Crystal structure of the complete modular teichioic acid phosphorylcholine esterase pce (cbpe) from streptococcus pneumoniae

Structure:

Teichoic acid phosphorylcholine esterase/ choline protein. Chain: a. Fragment: residues 26-572. Synonym: cbpe. Engineered: yes

Source:

Streptococcus pneumoniae. Organism_taxid: 1313. Expressed in: escherichia coli. Expression_system_taxid: 562

Resolution:

1.92Å R-factor: 0.197 R-free: 0.233

Authors:

J.A.Hermoso,L.Lagartera,A.Gonzalez,P.Garcia,M.Martinez-Ripol J.L.Garcia,M.Menendez

Key ref:

J.A.Hermoso et al. (2005). Insights into pneumococcal pathogenesis from the crystal structure of the modular teichoic acid phosphorylcholine esterase Pce. Nat Struct Mol Biol, 12, 533-538. PubMed id: 15895092 DOI: 10.1038/nsmb940

Date:

20-Jan-05 Release date: 09-May-05

Protein chain

Q8DQ62  (Q8DQ62_STRR6) -  Teichoic acid phosphorylcholine esterase/choline binding protein E (CbpE)

Seq: 627 a.a.

Struc: 542 a.a.

 Gene Ontology (GO) functional annotation 

• Biochemical function: hydrolase activity (1 term)

DOI no: 10.1038/nsmb940

Nat Struct Mol Biol 12:533-538 (2005)

PubMed id: 15895092

Insights into pneumococcal pathogenesis from the crystal structure of the modular teichoic acid phosphorylcholine esterase Pce.

J.A.Hermoso, L.Lagartera, A.González, M.Stelter, P.García, M.Martínez-Ripoll, J.L.García, M.Menéndez.

ABSTRACT

Phosphorylcholine, a specific component of the pneumococcal cell wall, is crucial in pathogenesis. It directly binds to the human platelet-activating factor (PAF) receptor and acts as a docking station for the family of surface-located choline-binding proteins (CBP). The first structure of a complete pneumococcal CBP, Pce (or CbpE), has been solved in complex with the reaction product and choline analogs. Pce has a novel modular structure, with a globular N-terminal module containing a binuclear Zn(2+) catalytic center, and an elongated choline-binding module. Residues involved in substrate binding and catalysis are described and modular configuration of the active center accounts for in vivo features of teichoic acid hydrolysis. The hydrolysis of PAF by Pce and its regulatory role in phosphorylcholine decoration of the bacterial surface provide new insights into the critical function of Pce in pneumococcal adherence and invasiveness.

Selected figure(s)

Figure 1.
Figure 1. Structure of Pce in complex with PC and choline analogs. (a) View of the Pce structure with modules colored differently: N-terminal catalytic module, blue; choline-binding module, yellow; linker, orange. The loop (residues 36 -61) involved in intermodular interactions is cyan. The PC molecule at the active site is in ball-and-stick, whereas Bis-Tris molecules bound to the choline-binding sites and metal ions (Zn, yellow; Ca, dark red) are spheres. Side chains for the two putative binding sites (the first one formed by residues from repeat p1, and the second one by residues from p10 and C-tail region) are shown. Residues blocking choline binding at the p8-p9 interface are also in ball-and-stick. (b) The Pce molecular surface colored according to its electrostatic potential. The yellow dotted line denotes the boundary between modules. The PC molecule (green) and Bis-Tris molecules (orange) are spheres.

Figure 2.
Figure 2. Metal-binding sites in Pce. (a) Stereo view showing the contact network at the active site. Broken lines indicate bonds between PC and Zn2+ ions with Pce residues (Zn1: His85, His87 and Asn183; Zn2: Asp89, His90 and His229; Asp203 bridges both Zn2+ ions). Interactions of phosphate oxygens from PC with two waters (red spheres) are omitted for clarity. (b) Close-up, stick representation view of calcium cluster showing the pentagonal bipyramidal ligation of the calcium ions with the relevant Pce residues; residues from loop 36 -61 are cyan.

The above figures are reprinted by permission from Macmillan Publishers Ltd: Nat Struct Mol Biol (2005, 12, 533-538) copyright 2005.

Figures were selected by an automated process.