TY - JOUR
T1 - An X-ray diffraction and X-ray absorption spectroscopy joint study of neuroglobin.
AU - Arcovito, Alessandro
AU - Moschetti, Tommaso
AU - D'Angelo, Paola
AU - Mancini, Giordano
AU - Vallone, Beatrice
AU - Brunori, Maurizio
AU - Della Longa, Stefano
PY - 2008
Y1 - 2008
N2 - Neuroglobin (Ngb) is a member of the globin family expressed in the vertebrate brain, involved in neuroprotection. A combined approach of X-ray diffraction (XRD) on single crystal and X-ray absorption spectroscopy (XAS) in solution, allows to determine the oxidation state and the structure of the Fe-heme both in the bis-histidine and the CO-bound (NgbCO) states. The overall data demonstrate that under Xray the iron is photoreduced fairly rapidly, and that the previously reported X-ray structure of ferric Ngb [B. Vallone, K. Nienhaus, M. Brunori, G.U. Nienhaus, Proteins 56 (2004) 85-92] very likely refers to a photoreduced species indistinguishable from the dithionite reduced protein. Results from the XAS analysis of NgbCO in solution are in good agreement with XRD data on the crystal. However prolonged X-ray exposure at 15 K determines CO release. This preliminary result paves the way to experiments aimed at the characterization of pentacoordinate ferrous Ngb, the only species competent in binding external ligands such as O-2, CO or NO
AB - Neuroglobin (Ngb) is a member of the globin family expressed in the vertebrate brain, involved in neuroprotection. A combined approach of X-ray diffraction (XRD) on single crystal and X-ray absorption spectroscopy (XAS) in solution, allows to determine the oxidation state and the structure of the Fe-heme both in the bis-histidine and the CO-bound (NgbCO) states. The overall data demonstrate that under Xray the iron is photoreduced fairly rapidly, and that the previously reported X-ray structure of ferric Ngb [B. Vallone, K. Nienhaus, M. Brunori, G.U. Nienhaus, Proteins 56 (2004) 85-92] very likely refers to a photoreduced species indistinguishable from the dithionite reduced protein. Results from the XAS analysis of NgbCO in solution are in good agreement with XRD data on the crystal. However prolonged X-ray exposure at 15 K determines CO release. This preliminary result paves the way to experiments aimed at the characterization of pentacoordinate ferrous Ngb, the only species competent in binding external ligands such as O-2, CO or NO
KW - EXAFS
KW - XANES
KW - neuroglobin
KW - EXAFS
KW - XANES
KW - neuroglobin
UR - http://hdl.handle.net/10807/6786
M3 - Article
SN - 0003-9861
SP - 7
EP - 13
JO - Archives of Biochemistry and Biophysics
JF - Archives of Biochemistry and Biophysics
ER -