1DKI

CRYSTAL STRUCTURE OF THE ZYMOGEN FORM OF STREPTOCOCCAL PYROGENIC EXOTOXIN B ACTIVE SITE (C47S) MUTANT

Summary for 1DKI

• Entry DOI: 10.2210/pdb1dki/pdb
• Descriptor: PYROGENIC EXOTOXIN B ZYMOGEN, SULFATE ION (3 entities in total)
• Functional Keywords: zymogen, cysteine protease, papain-like, toxin
• Biological source: Streptococcus pyogenes
• Cellular location: Secreted: P0C0J0
• Total number of polymer chains: 4
• Total formula weight: 161658.36

Authors

Kagawa, T.F.,Cooney, J.C.,Baker, H.M.,McSweeney, S.,Liu, M.,Gubba, S.,Musser, J.M.,Baker, E.N. (deposition date: 1999-12-07, release date: 2000-03-01, Last modification date: 2024-02-07)

Primary citation

Kagawa, T.F.,Cooney, J.C.,Baker, H.M.,McSweeney, S.,Liu, M.,Gubba, S.,Musser, J.M.,Baker, E.N.
Crystal structure of the zymogen form of the group A Streptococcus virulence factor SpeB: an integrin-binding cysteine protease.
Proc.Natl.Acad.Sci.USA, 97:2235-2240, 2000

PubMed Abstract: Pathogenic bacteria secrete protein toxins that weaken or disable their host, and thereby act as virulence factors. We have determined the crystal structure of streptococcal pyrogenic exotoxin B (SpeB), a cysteine protease that is a major virulence factor of the human pathogen Streptococcus pyogenes and participates in invasive disease episodes, including necrotizing fasciitis. The structure, determined for the 40-kDa precursor form of SpeB at 1.6-A resolution, reveals that the protein is a distant homologue of the papain superfamily that includes the mammalian cathepsins B, K, L, and S. Despite negligible sequence identity, the protease portion has the canonical papain fold, albeit with major loop insertions and deletions. The catalytic site differs from most other cysteine proteases in that it lacks the Asn residue of the Cys-His-Asn triad. The prosegment has a unique fold and inactivation mechanism that involves displacement of the catalytically essential His residue by a loop inserted into the active site. The structure also reveals the surface location of an integrin-binding Arg-Gly-Asp (RGD) motif that is a feature unique to SpeB among cysteine proteases and is linked to the pathogenesis of the most invasive strains of S. pyogenes.

PubMed: 10681429
DOI: 10.1073/pnas.040549997

Experimental method

X-RAY DIFFRACTION (1.6 Å)