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1dm0
From Proteopedia
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| , resolution 2.5Å | |||||||
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| Activity: | rRNA N-glycosylase, with EC number 3.2.2.22 | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
SHIGA TOXIN
Overview
Shigella dysenteriae is the pathogen responsible for the severe form of dysentery in humans. It produces Shiga toxin, the prototype of a family of closely related bacterial protein toxins. We have determined the structure of the holotoxin, an AB5 hexamer, by X-ray crystallography. The five B subunits form a pentameric ring, encircling a helix at the carboxy terminus of the A subunit. The A subunit interacts with the B pentamer via this C-terminal helix and a four-stranded mixed beta-sheet. The fold of the rest of the A subunit is similar to that of the A chain of the plant toxin ricin; both are N-glycosidases. However, the active site in the bacterial holotoxin is blocked by a segment of polypeptide chain. These residues of the A subunit would be released as part of the activation mechanism of the toxin.
About this Structure
1DM0 is a Protein complex structure of sequences from Shigella dysenteriae. Full crystallographic information is available from OCA.
Reference
Crystal structure of the holotoxin from Shigella dysenteriae at 2.5 A resolution., Fraser ME, Chernaia MM, Kozlov YV, James MN, Nat Struct Biol. 1994 Jan;1(1):59-64. PMID:7656009
Page seeded by OCA on Sun Mar 30 19:44:07 2008
