1VLX

STRUCTURE OF ELECTRON TRANSFER (COBALT-PROTEIN)

Summary for 1VLX

• Entry DOI: 10.2210/pdb1vlx/pdb
• Descriptor: AZURIN, COBALT (II) ION (3 entities in total)
• Functional Keywords: electron transport, copper, periplasmic
• Biological source: Pseudomonas aeruginosa
• Cellular location: Periplasm: P00282
• Total number of polymer chains: 4
• Total formula weight: 56082.93

Authors

Bonander, N.,Vanngard, T.,Tsai, L.-C.,Langer, V.,Nar, H.,Sjolin, L. (deposition date: 1996-10-08, release date: 1997-03-12, Last modification date: 2024-10-16)

Primary citation

Bonander, N.,Vanngard, T.,Tsai, L.C.,Langer, V.,Nar, H.,Sjolin, L.
The metal site of Pseudomonas aeruginosa azurin, revealed by a crystal structure determination of the Co(II) derivative and Co-EPR spectroscopy.
Proteins, 27:385-394, 1997

PubMed Abstract: The crystal structure of cobalt-substituted azurin from Pseudomonas aeruginosa has been determined to final crystallographic R value of 0.175 at 1.9 A resolution. There are four molecules in the asymmetric unit in the structure, and these four molecules are packed as a dimer of dimers. The dimer packing is very similar to that of the wild-type Pseudomonas aeruginosa azurin dimer. Replacement of the native copper by the cobalt ion has only small effects on the metal binding site presumably because of the existence of an extensive network of hydrogen bonds in its immediate neighborhood. Some differences are obvious, however. In wild-type azurin the copper atom occupies a distorted trigonal bipyramidal site, while cobalt similar to zinc and nickel occupy a distorted tetrahedral site, in which the distance to the Met121,S(delta) atom is increased to 3.3-3.5 A and the distance to the carbonyl oxygen of Gly45 has decreased to 2.1-2.4 A. The X-band EPR spectrum of the high-spin Co(II) in azurin is well resolved (apparent g values gx' = 5.23; gy' = 3.83; gz' = 1.995, and hyperfine splittings Ax' = 31; Ay' = 20-30; Az' = 53 G) and indicates that the ligand field is close to axial.

PubMed: 9094740
DOI: 10.1002/(SICI)1097-0134(199703)27:3<385::AID-PROT6>3.0.CO;2-C

Experimental method

X-RAY DIFFRACTION (1.9 Å)