1E65

Azurin from Pseudomonas aeruginosa, apo form

Summary for 1E65

• Entry DOI: 10.2210/pdb1e65/pdb
• Descriptor: AZURIN (2 entities in total)
• Functional Keywords: electron transport, copper binding
• Biological source: PSEUDOMONAS AERUGINOSA
• Cellular location: Periplasm: P00282
• Total number of polymer chains: 4
• Total formula weight: 55847.20

Authors

Nar, H.,Messerschmidt, A. (deposition date: 2000-08-08, release date: 2000-08-16, Last modification date: 2017-07-12)

Primary citation

Nar, H.,Messerschmidt, A.,Huber, R.,Van De Kamp, M.,Canters, G.W.
Crystal Structure of Pseudomonas Aeruginosa Apo-Azurin at 1.85 A Resolution.
FEBS Lett., 306:119-, 1992

PubMed Abstract: The 3D structure of apo-azurin from Pseudomonas aeruginosa has been determined at 1.85 A resolution. The crystal structure is composed of two different molecular forms of apo-azurin arranged as hetero-dimers in the tetramer of the asymmetric unit. Form 1 closely resembles the holo-protein lacking copper. Form 2 shows differences in the metal binding site region induced by the incorporation of a solvent molecule into this site. The positions of the copper ligands His46 and His117 are shifted by 0.6 A and 1.6 A. The His117 side chain adopts a position at the surface of the protein, thereby facilitating access to the copper site. The presence of two different molecular forms of apo-azurin in the crystal lattice may reflect an equilibrium between the two forms in solution. 1H-NMR spectra of apo-azurin recorded as a function of pH show that at high pH the line broadening of His35, His46 and His117 resonances is consistent with an interconversion between forms 1 and 2. At low pH, no broadening is observed. This may indicate that here the interconversion is fast on the NMR timescale.

PubMed: 1633865
DOI: 10.1016/0014-5793(92)80981-L

Experimental method

X-RAY DIFFRACTION (1.85 Å)