2j3v
From Proteopedia
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CRYSTAL STRUCTURE OF THE ENZYMATIC COMPONENT C2-I OF THE C2-TOXIN FROM CLOSTRIDIUM BOTULINUM AT PH 3.0
Overview
C2 toxin from Clostridium botulinum is composed of the enzyme component, C2-I, which ADP-ribosylates actin, and the binding and translocation, component C2-II, responsible for the interaction with eukaryotic cell, receptors and the following endocytosis. Three C2-I crystal structures at, resolutions of up to 1.75 A are presented together with a crystal, structure of C2-II at an appreciably lower resolution and a model of the, prepore formed by fragment C2-IIa. The C2-I structure was determined at pH, 3.0 and at pH 6.1. The structural differences are small, indicating that, C2-I does not unfold, even at a pH value as low as 3.0. The ADP-ribosyl, transferase activity of C2-I was determined for alpha and beta/gamma-actin, and related to that of Iota toxin and of mutant S361R of C2-I that, introduced the arginine observed in Iota toxin. The substantial activity, differences between alpha and beta/gamma-actin cannot be explained by the, protein structures currently available. The structure of the transport, component C2-II at pH 4.3 was established by molecular replacement using a, model of the protective antigen of anthrax toxin at pH 6.0. The C-terminal, receptor-binding domain of C2-II could not be located but was present in, the crystals. It may be mobile. The relative orientation and positions of, the four other domains of C2-II do not differ much from those of the, protective antigen, indicating that no large conformational changes occur, between pH 4.3 and pH 6.0. A model of the C2-IIa prepore structure was, constructed based on the corresponding assembly of the protective antigen., It revealed a surprisingly large number of asparagine residues lining the, pore. The interaction between C2-I and C2-IIa and the translocation of, C2-I into the target cell are discussed.
About this Structure
2J3V is a Single protein structure of sequence from Clostridium botulinum with SO4 and GOL as ligands. Structure known Active Site: AC1. Full crystallographic information is available from OCA.
Reference
Structure and action of the binary C2 toxin from Clostridium botulinum., Schleberger C, Hochmann H, Barth H, Aktories K, Schulz GE, J Mol Biol. 2006 Dec 8;364(4):705-15. Epub 2006 Sep 5. PMID:17027031
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