PDBsum entry 4g9s

Hydrolase/hydrolase inhibitor

PDB id: 4g9s

Contents

Protein chains

187 a.a.

111 a.a.

Ligands

FLC

Metals

_CL

Waters ×541

PDB id:

4g9s

Name:

Hydrolase/hydrolase inhibitor

Title:

Crystal structure of escherichia coli plig in complex with atlantic salmon g-type lysozyme

Structure:

Goose-type lysozyme. Chain: a. Fragment: unp residues 22-200. Synonym: lysozyme g. Engineered: yes. Mutation: yes. Inhibitor of g-type lysozyme. Chain: b. Fragment: unp residues 23-133.

Source:

Salmo salar. Atlantic salmon. Organism_taxid: 8030. Gene: lysg, lyg. Expressed in: escherichia coli. Expression_system_taxid: 469008. Escherichia coli. Organism_taxid: 562. Gene: plig, ycgk.

Resolution:

0.95Å R-factor: 0.129 R-free: 0.136

Authors:

S.Leysen,L.Vanderkelen,S.D.Weeks,C.W.Michiels,S.V.Strelkov

Key ref:

S.Leysen et al. (2013). Structural basis of bacterial defense against g-type lysozyme-based innate immunity. Cell Mol Life Sci, 70, 1113-1122. PubMed id: 23086131 DOI: 10.1007/s00018-012-1184-1

Date:

24-Jul-12 Release date: 07-Nov-12

Protein chain

A6PZ97  (A6PZ97_SALSA) -  Lysozyme g from Salmo salar

Seq: 200 a.a.

Struc: 187 a.a.*

Protein chain

P76002  (PLIG_ECOLI) -  Inhibitor of g-type lysozyme from Escherichia coli (strain K12)

Seq: 133 a.a.

Struc: 111 a.a.

* PDB and UniProt seqs differ at 9 residue positions (black crosses)

Enzyme reactions

• Enzyme class: Chain A: E.C.3.2.1.17 - lysozyme.
• Reaction: Hydrolysis of the 1,4-beta-linkages between N-acetyl-D-glucosamine and N-acetylmuramic acid in peptidoglycan heteropolymers of the prokaryotes cell walls.

DOI no: 10.1007/s00018-012-1184-1

Cell Mol Life Sci 70:1113-1122 (2013)

PubMed id: 23086131

Structural basis of bacterial defense against g-type lysozyme-based innate immunity.

S.Leysen, L.Vanderkelen, S.D.Weeks, C.W.Michiels, S.V.Strelkov.

ABSTRACT

Gram-negative bacteria can produce specific proteinaceous inhibitors to defend themselves against the lytic action of host lysozymes. So far, four different lysozyme inhibitor families have been identified. Here, we report the crystal structure of the Escherichia coli periplasmic lysozyme inhibitor of g-type lysozyme (PliG-Ec) in complex with Atlantic salmon g-type lysozyme (SalG) at a resolution of 0.95 Å, which is exceptionally high for a complex of two proteins. The structure reveals for the first time the mechanism of g-type lysozyme inhibition by the PliG family. The latter contains two specific conserved regions that are essential for its inhibitory activity. The inhibitory complex formation is based on a double 'key-lock' mechanism. The first key-lock element is formed by the insertion of two conserved PliG regions into the active site of the lysozyme. The second element is defined by a distinct pocket of PliG accommodating a lysozyme loop. Computational analysis indicates that this pocket represents a suitable site for small molecule binding, which opens an avenue for the development of novel antibacterial agents that suppress the inhibitory activity of PliG.