1BQK

OXIDIZED PSEUDOAZURIN

Summary for 1BQK

• Entry DOI: 10.2210/pdb1bqk/pdb
• Descriptor: PSEUDOAZURIN, COPPER (II) ION (3 entities in total)
• Functional Keywords: cuproprotein, electron transport
• Biological source: Achromobacter cycloclastes
• Cellular location: Periplasm: P19567
• Total number of polymer chains: 1
• Total formula weight: 13096.49

Authors

Inoue, T.,Nishio, N.,Hamanaka, S.,Shimomura, T.,Harada, S.,Suzuki, S.,Kohzuma, T.,Shidara, S.,Iwasaki, H.,Kai, Y. (deposition date: 1998-08-17, release date: 1999-08-17, Last modification date: 2024-05-22)

Primary citation

Inoue, T.,Nishio, N.,Suzuki, S.,Kataoka, K.,Kohzuma, T.,Kai, Y.
Crystal structure determinations of oxidized and reduced pseudoazurins from Achromobacter cycloclastes. Concerted movement of copper site in redox forms with the rearrangement of hydrogen bond at a remote histidine.
J.Biol.Chem., 274:17845-17852, 1999

PubMed Abstract: The crystal structures of oxidized and reduced pseudoazurins from a denitrifying bacterium, Achromobacter cycloclastes IAM1013, have been determined at 1.35- and 1.6-A resolutions, respectively. The copper site in the oxidized state exhibits a distorted tetrahedral structure like those of other pseudoazurins. However, not only a small change of the copper geometry, but concerted peptide bond flips are identified. The imidazole ring of remote His6 has a hydrogen bonding distance of 2.73 A between N-delta1(His6) and O-gamma1(Thr36) in the oxidized protein. When the protein is reduced at pH 6.0, the imidazole ring rotates by 30.3 degrees and moves 1.00 A away from the position of the oxidized state. A new hydrogen bond between N-epsilon2(His6) and O-epsilon1(Glu4) is formed with a distance of 3.03 A, while the hydrogen bond between N-delta1(His6)-O-gamma1(Thr36) is maintained with an interatomic distance of 2.81 A. A concomitant peptide bond flip of main chain between Ile34 and Thr36 occurs.

PubMed: 10364229
DOI: 10.1074/jbc.274.25.17845

Experimental method

X-RAY DIFFRACTION (1.35 Å)