1m24
From Proteopedia
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Trichotoxin_A50E, An Ion Channel-Forming Polypeptide
Overview
Trichotoxin_A50E is an 18-residue peptaibol antibiotic which forms, multimeric transmembrane channels through self-association. The crystal, structure of trichotoxin has been determined at a resolution of 0.9 A. The, trichotoxin sequence contains nine helix-promoting Aib residues, which, contribute to the formation of an entirely helical structure that has a, central bend of 8-10 degrees located between residues 10-13. Trichotoxin, is the first solved structure of the peptaibol family that is all, alpha-helix as opposed to containing part or all 3(10)-helix. Gln residues, in positions 6 and 17 produce a polar face, and are proposed to form the, channel lumen. An octameric model channel has been constructed from the, crystal structure. It has a central pore of approximately 4-5 A radius, a, size sufficient to enable transport of ions, with a constricted region at, one end, formed by a ring of Gln6 residues. Electrostatic calculations are, consistent with it being a cationic channel.
About this Structure
1M24 is a Protein complex structure of sequences from Trichoderma viride with ACE and CCN as ligands. Full crystallographic information is available from OCA.
Reference
Model for a helical bundle channel based on the high-resolution crystal structure of trichotoxin_A50E., Chugh JK, Bruckner H, Wallace BA, Biochemistry. 2002 Oct 29;41(43):12934-41. PMID:12390019
Page seeded by OCA on Sun Nov 25 03:40:50 2007
