PDBsum entry 4yo1

Hydrolase

PDB id: 4yo1

Contents

Protein chain

276 a.a.

Metals

_CD ×5

PDB id:

4yo1

Name:

Hydrolase

Title:

Structure of legionella pneumophila degq (delta pdz2 variant)

Structure:

Degq. Chain: a. Fragment: unp residues 31-369. Engineered: yes. Mutation: yes

Source:

Legionella pneumophila. Organism_taxid: 446. Gene: htra, lpg1331. Expressed in: escherichia coli. Expression_system_taxid: 562.

Resolution:

2.80Å R-factor: 0.222 R-free: 0.275

Authors:

R.Wrase,R.Hilgenfeld,G.Hansen

Key ref:

A.Schubert et al. (2015). Structures of DegQ from Legionella pneumophila Define Distinct ON and OFF States. J Mol Biol, 427, 2840-2851. PubMed id: 26205420 DOI: 10.1016/j.jmb.2015.06.023

Date:

11-Mar-15 Release date: 24-Jun-15

Protein chain

Q5ZVV9  (Q5ZVV9_LEGPH) -  Protease DO from Legionella pneumophila subsp. pneumophila (strain Philadelphia 1 / ATCC 33152 / DSM 7513)

Seq: 466 a.a.

Struc: 276 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

Enzyme reactions

• Enzyme class: E.C.3.4.21.- - ?????

DOI no: 10.1016/j.jmb.2015.06.023

J Mol Biol 427:2840-2851 (2015)

PubMed id: 26205420

Structures of DegQ from Legionella pneumophila Define Distinct ON and OFF States.

A.Schubert, R.Wrase, R.Hilgenfeld, G.Hansen.

ABSTRACT

HtrA (high-temperature requirement A) family proteins play important roles in protein-quality control processes in the bacterial periplasm. A common feature of all members of this family is their modular organization comprising a chymotrypsin-like protease domain and at least one PDZ (postsynaptic density of 95kDa, disks large homolog 1 and zonula occludens 1) domain. All characterized HtrA proteins assemble into complex oligomers consisting of typically 3-24 monomers, which allow a tight regulation of proteolytic activity. Here, we provide evidence that the assembly of proteolytically active, higher-order complexes of DegQ from Legionella pneumophila is triggered by the binding of substrate-derived peptides. Crystal structures of inactive 3-mers and active 12-mers of DegQ reveal molecular details of elements of a conserved allosteric activation cascade that defines distinct protease ON and OFF states. Results from DegQLp variants harboring structure-based amino acid substitutions indicate that peptide binding to the PDZ1 domain is critical for proteolytic activity but not for the formation of higher-order oligomers. Combining structural, mutagenesis and biochemical data, we show that, in contrast to the proteolytic activity, the chaperone function of DegQ is not affected by the state of the activation cascade.