1FNV

STRUCTURE OF STREPTOCOCCAL PYROGENIC EXOTOXIN A

1FNV の概要

• エントリーDOI: 10.2210/pdb1fnv/pdb
• 関連するPDBエントリー: 1FNU 1FNW
• 分子名称: EXOTOXIN TYPE A PRECURSOR (ALLELE 1), CADMIUM ION (2 entities in total)
• 機能のキーワード: exotoxin a, superantigen, toxin
• 由来する生物種: Streptococcus pyogenes phage T12
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 105246.97

構造登録者

Earhart, C.A.,Vath, G.M.,Roggiani, M.,Schlievert, P.M.,Ohlendorf, D.H. (登録日: 2000-08-23, 公開日: 2000-11-17, 最終更新日: 2024-10-30)

主引用文献

Earhart, C.A.,Vath, G.M.,Roggiani, M.,Schlievert, P.M.,Ohlendorf, D.H.
Structure of streptococcal pyrogenic exotoxin A reveals a novel metal cluster.
Protein Sci., 9:1847-1851, 2000

PubMed Abstract: The streptococcal pyrogenic toxins A, B, and C (SPEA, SPEB, and SPEC) are responsible for the fever, rash, and other toxicities associated with scarlet fever and streptococcal toxic shock syndrome. This role, together with the ubiquity of diseases caused by Streptococcus pyogenes, have prompted structural analyses of SPEA by several groups. Papageorgiou et al. (1999) have recently reported the structure of SPEA crystallized in the absence of zinc. Zinc has been shown to be important in the ability of some staphylococcal and streptococcal toxins to stimulate proliferation of CD4+ T-cells. Since cadmium is more electron dense than zinc and typically binds interchangeably, we grew crystals in the presence of 10 mM CdCl2. Crystals have been obtained in three space groups, and the structure in the P2(1)2(1)2(1) crystal form has been refined to 1.9 A resolution. The structural analysis revealed an identical tetramer as well as a novel tetrahedral cluster of cadmium in all three crystal forms on a disulfide loop encompassing residues 87-98. No cadmium was bound at the site homologous to the zinc site in staphylococcal enterotoxins C (SECs) despite the high structural homology between SPEA and SECs. Subsequent soaking of crystals grown in the presence of cadmium in 10 mM ZnCl2 showed that zinc binds in this site (indicating it can discriminate between zinc and cadmium ions) using the three ligands (Asp77, His106, and His110) homologous to the SECs plus a fourth ligand (Glu33).

PubMed: 11045630

実験手法

X-RAY DIFFRACTION (3.6 Å)