PDBsum entry: 1dt2

Toxin, hydrolase

PDB id: 1dt2

Contents

Protein chain

245 a.a. *

Waters ×9

* Residue conservation analysis

PDB id:

1dt2

Name:

Toxin, hydrolase

Title:

Crystal structure of exfoliative toxin b

Structure:

Exfoliative toxin b. Chain: a. Engineered: yes

Source:

Staphylococcus aureus. Organism_taxid: 1280. Expressed in: escherichia coli. Expression_system_taxid: 562. Other_details: chromosomal DNA of s. Aureus isolated from a patient with staphylococcal scalded skin disease

Biol. unit:

Dimer (from PQS)

Resolution:

2.80Å R-factor: 0.224 R-free: 0.251

Authors:

A.C.Papageorgiou,L.R.W.Plano,C.M.Collins,K.R.Acharya

Key ref:

A.C.Papageorgiou et al. (2000). Structural similarities and differences in Staphylococcus aureus exfoliative toxins A and B as revealed by their crystal structures. Protein Sci, 9, 610-618. PubMed id: 10752623 Ref: Full text

Date:

11-Jan-00 Release date: 21-Jan-03

Protein chain

P09332  (ETB_STAAU) -  Exfoliative toxin B

Seq: 277 a.a.

Struc: 245 a.a.

 Gene Ontology (GO) functional annotation 

• Biological process: pathogenesis (2 terms)
• Biochemical function: catalytic activity (5 terms)

Full text	Protein Sci 9:610-618 (2000)
PubMed id: 10752623

Structural similarities and differences in Staphylococcus aureus exfoliative toxins A and B as revealed by their crystal structures.

A.C.Papageorgiou, L.R.Plano, C.M.Collins, K.R.Acharya.

ABSTRACT

Staphylococcal aureus epidermolytic toxins (ETs) A and B are responsible for the induction of staphylococcal scalded skin syndrome, a disease of neonates and young children. The clinical features of this syndrome vary from localized blisters to severe exfoliation affecting most of the body surface. Comparison of the crystal structures of two subtypes of ETs-rETA (at 2.0 A resolution), rETB (at 2.8 A resolution), and an active site variant of rETA, Ser195Ala at 2.0 A resolution has demonstrated that their overall topology resembles that of a "trypsin-like" serine protease, but with significant differences at the N- and C-termini and loop regions. The details of the catalytic site in both ET structures are very similar to those in glutamate-specific serine proteases, suggesting a common catalytic mechanism. However, the "oxyanion hole," which is part of the catalytic sites of glutamate specific serine proteases, is in the closed or inactive conformation for rETA, yet in the open or active conformation for rETB. The ETs contain a unique amphipathic helix at the N-terminus, and it appears to be involved in optimizing the conformation of the catalytic site residues. Determination of the structure of the rETA catalytic site variant, Ser195Ala, showed no significant perturbation at the active site, establishing that the loss of biological and esterolytic activity can be attributed solely to disruption of the catalytic serine residue. Finally, the crystal structure of ETs, together with biochemical data and mutagenesis studies, strongly confirms the classification of these molecules as "serine proteases" rather than "superantigens."