PDBsum entry 5vba

Chaperone, hydrolase

PDB id: 5vba

Contents

Protein chains

408 a.a.

Metals

_CL ×10

Waters ×56

PDB id:

5vba

Name:

Chaperone, hydrolase

Title:

Structure of espg1 chaperone from the type vii (esx-1) secretion system determined with the assistance of n-terminal t4 lysozyme fusion

Structure:

Lysozyme, esx-1 secretion-associated protein espg1 chimera. Chain: a, b. Fragment: t4 lysozyme (unp residues 2-162) + espg1 (unp residues 16- 271). Synonym: espg1. Engineered: yes. Mutation: yes

Source:

Enterobacteria phage t4, mycobacterium kansasii atcc 12478. Organism_taxid: 10665, 557599. Gene: e, t4tp126. Expressed in: escherichia coli bl21(de3). Expression_system_taxid: 469008

Resolution:

2.27Å R-factor: 0.216 R-free: 0.251

Authors:

K.V.Korotkov

Key ref:

A.T.Tuukkanen et al. (2019). Structural Variability of EspG Chaperones from Mycobacterial ESX-1, ESX-3, and ESX-5 Type VII Secretion Systems. J Mol Biol, 431, 289-307. PubMed id: 30419243 DOI: 10.1016/j.jmb.2018.11.003

Date:

29-Mar-17 Release date: 05-Jul-17

Protein chains

P00720  (ENLYS_BPT4) -  Endolysin from Enterobacteria phage T4

Seq: 164 a.a.

Struc: 408 a.a.*

Protein chains

X7YCN8  (X7YCN8_MYCKA) -  ESX-1 secretion-associated protein EspG1 from Mycobacterium kansasii 824

Seq: 283 a.a.

Struc: 408 a.a.*

* PDB and UniProt seqs differ at 24 residue positions (black crosses)

Enzyme reactions

• Enzyme class: 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: 10.1016/j.jmb.2018.11.003

J Mol Biol 431:289-307 (2019)

PubMed id: 30419243

Structural Variability of EspG Chaperones from Mycobacterial ESX-1, ESX-3, and ESX-5 Type VII Secretion Systems.

A.T.Tuukkanen, D.Freire, S.Chan, M.A.Arbing, R.W.Reed, T.J.Evans, G.Zenkeviciutė, J.Kim, S.Kahng, M.R.Sawaya, C.T.Chaton, M.Wilmanns, D.Eisenberg, A.H.A.Parret, K.V.Korotkov.

ABSTRACT

Type VII secretion systems (ESX) are responsible for transport of multiple proteins in mycobacteria. How different ESX systems achieve specific secretion of cognate substrates remains elusive. In the ESX systems, the cytoplasmic chaperone EspG forms complexes with heterodimeric PE-PPE substrates that are secreted from the cells or remain associated with the cell surface. Here we report the crystal structure of the EspG₁ chaperone from the ESX-1 system determined using a fusion strategy with T4 lysozyme. EspG₁ adopts a quasi 2-fold symmetric structure that consists of a central β-sheet and two α-helical bundles. In addition, we describe the structures of EspG₃ chaperones from four different crystal forms. Alternate conformations of the putative PE-PPE binding site are revealed by comparison of the available EspG₃ structures. Analysis of EspG₁, EspG₃, and EspG₅ chaperones using small-angle X-ray scattering reveals that EspG₁ and EspG₃ chaperones form dimers in solution, which we observed in several of our crystal forms. Finally, we propose a model of the ESX-3 specific EspG₃-PE5-PPE4 complex based on the small-angle X-ray scattering analysis.