1QHQ

AURACYANIN, A BLUE COPPER PROTEIN FROM THE GREEN THERMOPHILIC PHOTOSYNTHETIC BACTERIUM CHLOROFLEXUS AURANTIACUS

Summary for 1QHQ

• Entry DOI: 10.2210/pdb1qhq/pdb
• Descriptor: PROTEIN (AURACYANIN), COPPER (II) ION, CHLORIDE ION, ... (5 entities in total)
• Functional Keywords: electron transfer, cupredoxin, blue copper protein, azurin-like, thermophile
• Biological source: Chloroflexus aurantiacus
• Cellular location: Membrane; Peripheral membrane protein: P27197
• Total number of polymer chains: 1
• Total formula weight: 14702.09

Authors

Bond, C.S.,Blankenship, R.E.,Freeman, H.C.,Guss, J.M.,Maher, M.,Selvaraj, F.,Wilce, M.C.J.,Willingham, K. (deposition date: 1999-05-25, release date: 2001-03-07, Last modification date: 2023-12-27)

Primary citation

Bond, C.S.,Blankenship, R.E.,Freeman, H.C.,Guss, J.M.,Maher, M.J.,Selvaraj, F.M.,Wilce, M.C.,Willingham, K.M.
Crystal structure of auracyanin, a "blue" copper protein from the green thermophilic photosynthetic bacterium Chloroflexus aurantiacus.
J.Mol.Biol., 306:47-67, 2001

PubMed Abstract: Auracyanin B, one of two similar blue copper proteins produced by the thermophilic green non-sulfur photosynthetic bacterium Chloroflexus aurantiacus, crystallizes in space group P6(4)22 (a=b=115.7 A, c=54.6 A). The structure was solved using multiple wavelength anomalous dispersion data recorded about the CuK absorption edge, and was refined at 1.55 A resolution. The molecular model comprises 139 amino acid residues, one Cu, 247 H(2)O molecules, one Cl(-) and two SO(4)(2-). The final residual and estimated standard uncertainties are R=0.198, ESU=0.076 A for atomic coordinates and ESU=0.05 A for Cu---ligand bond lengths, respectively. The auracyanin B molecule has a standard cupredoxin fold. With the exception of an additional N-terminal strand, the molecule is very similar to that of the bacterial cupredoxin, azurin. As in other cupredoxins, one of the Cu ligands lies on strand 4 of the polypeptide, and the other three lie along a large loop between strands 7 and 8. The Cu site geometry is discussed with reference to the amino acid spacing between the latter three ligands. The crystallographically characterized Cu-binding domain of auracyanin B is probably tethered to the periplasmic side of the cytoplasmic membrane by an N-terminal tail that exhibits significant sequence identity with known tethers in several other membrane-associated electron-transfer proteins.

PubMed: 11178893
DOI: 10.1006/jmbi.2000.4201

Experimental method

X-RAY DIFFRACTION (1.55 Å)