Spin-density distribution in the copper site of azurin.
A 95 GHz pulsed deuterium ENDOR study has been performed on single crystals of azurin from Pseudomonas aeruginosa selectively deuterated at the C(beta) position of the copper-coordinating cysteine 112. Complete hyperfine tensors of the two deuterium atoms have been obtained, which reveal identical isotropic parts. Analysis of the hyperfine tensors provides insight into the spin-density delocalization over the cysteine ligand. Approximately 45 % of the spin density in the paramagnetic site can be attributed to copper and 30 % to sulfur.
Fittipaldi
Maria
M
Department of Molecular Physics, Huygens Laboratory, Leiden University, P.O. Box 9504, 2300 RA Leiden, The Netherlands. mat@molphys.leidenuniv.nl
Warmerdam
Gertrud C M
GC
de Waal
Ellen C
EC
Canters
Gerard W
GW
Cavazzini
Davide
D
Rossi
Gian Luigi
GL
Huber
Martina
M
Groenen
Edgar J J
EJ