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2g23
From Proteopedia
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| , resolution 2.30Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , , | ||||||
| Gene: | phsA (Streptomyces antibioticus) | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
The crystal structure of hexameric phenoxazinone synthase
Overview
The multicopper oxidase phenoxazinone synthase (PHS) catalyzes the penultimate step in the biosynthesis of the antibiotic actinomycin D by Streptomyces antibioticus. PHS exists in two oligomeric forms: a dimeric form and a hexameric form, with older actinomycin-producing cultures containing predominately the hexameric form. The structure of hexameric PHS has been determined using X-ray diffraction to a resolution limit of 2.30 A and is found to contain several unexpected and distinctive features. The structure forms a hexameric ring that is centered on a pseudo 6-fold axis and has an outer diameter of 185 A with a large central cavity that has a diameter of 50 A. This hexameric structure is stabilized by a long loop connecting two domains; bound to this long loop is a fifth copper atom that is present as a type 2 copper. This copper atom is not present in any other multicopper oxidase, and its presence appears to stabilize the hexameric structure.
About this Structure
2G23 is a Single protein structure of sequence from Streptomyces antibioticus. Full crystallographic information is available from OCA.
Reference
Structure of phenoxazinone synthase from Streptomyces antibioticus reveals a new type 2 copper center., Smith AW, Camara-Artigas A, Wang M, Allen JP, Francisco WA, Biochemistry. 2006 Apr 11;45(14):4378-87. PMID:16584173
Page seeded by OCA on Mon Mar 31 03:10:47 2008
