1QNN

Cambialistic superoxide dismutase from Porphyromonas gingivalis

Summary for 1QNN

• Entry DOI: 10.2210/pdb1qnn/pdb
• Descriptor: SUPEROXIDE DISMUTASE, FE (III) ION (3 entities in total)
• Functional Keywords: oxidoreductase
• Biological source: PORPHYROMONAS GINGIVALIS
• Total number of polymer chains: 4
• Total formula weight: 86335.91

Authors

Sugio, S.,Hiraoka, B.Y.,Yamakura, F. (deposition date: 1999-10-20, release date: 2000-06-21, Last modification date: 2023-12-13)

Primary citation

Sugio, S.,Hiraoka, B.Y.,Yamakura, F.
Crystal Structure of Cambialistic Superoxide Dismutase from Porphyromonas Gingivalis
Eur.J.Biochem., 267:3487-, 2000

PubMed Abstract: The crystal structure of cambialistic superoxide dismutase (SOD) from Porphyromonas gingivalis, which exhibits full activity with either Fe or Mn at the active site, has been determined at 1.8-A resolution by molecular replacement and refined to a crystallographic R factor of 17.9% (Rfree 22.3%). The crystals belong to the space group P212121 (a = 75.5 A, b = 102.7 A, c = 99.6 A) with four identical subunits in the asymmetric unit. Each pair of subunits forms a compact dimer, but not a tetramer, with 222 point symmetry. Each subunit has 191 amino-acid residues most of which are visible in electron density maps, and consists of seven alpha helices and one three-stranded antiparallel beta sheet. The metal ion, a 3 : 1 mixture of Fe and Mn, is coordinated with five ligands (His27, His74, His161, Asp157, and water) arranged at the vertices of a trigonal bipyramid. Although the overall structural features, including the metal coordination geometry, are similar to those found in other single-metal containing SODs, P. gingivalis SOD more closely resembles the dimeric Fe-SODs from Escherichia coli rather than another cambialistic SOD from Propionibacterium shermanii, which itself is rather similar to other tetrameric SODs.

PubMed: 10848964
DOI: 10.1046/J.1432-1327.2000.01373.X

Experimental method

X-RAY DIFFRACTION (1.8 Å)