 |
PDBsum entry 1exf
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Complex (toxin/peptide)
|
PDB id
|
|
|
|
1exf
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
 |
Contents |
 |
|
|
|
|
|
|
|
|
|
|
|
|
* Residue conservation analysis
|
|
|
|
|
References listed in PDB file
|
|
|
Key reference
|
|
|
Title
|
|
The structure of the superantigen exfoliative toxin a suggests a novel regulation as a serine protease.
|
|
|
Authors
|
|
G.M.Vath,
C.A.Earhart,
J.V.Rago,
M.H.Kim,
G.A.Bohach,
P.M.Schlievert,
D.H.Ohlendorf.
|
|
|
Ref.
|
|
Biochemistry, 1997,
36,
1559-1566.
[DOI no: ]
|
|
|
PubMed id
|
|
|
|
|
|
Abstract
|
|
|
Exfoliative toxin A (ETA) causes staphylococcal scalded skin syndrome which is
characterized by a specific intraepidermal separation of layers of the skin. The
mechanism by which ETA causes skin separation is unknown although protease or
superantigen activity has been implicated. The X-ray crystal structure of ETA
has been solved in two crystal forms to 2.1 and 2.3 A resolution and R-factors
of 17% and 19%, respectively. The structures indicate that ETA belongs to the
chymotrypsin-like family of serine proteases and cleaves substrates after acidic
residues. The conformation of a loop adjacent to the catalytic site is suggested
to be key in regulating the proteolytic activity of ETA through controlling
whether the main chain carbonyl group of Pro192 occupies the oxyanion hole. A
unique amino-terminal domain containing a 15-residue amphipathic alpha helix may
also be involved in protease activation through binding a specific receptor.
Substitution of the active site serine residue with cysteine abolishes the
ability of ETA to produce the characteristic separation of epidermal layers but
not its ability to induce T cell proliferation.
|
|
|
|
|
|
|
