Journal
JOURNAL OF PHYSICAL CHEMISTRY B
Volume 114, Issue 41, Pages 13223-13231Publisher
AMER CHEMICAL SOC
DOI: 10.1021/jp104395g
Keywords
-
Categories
Funding
- Italian Ministry of University and Research (INCUR)
- MiUR of Italy [FIRB RBLA03B3KC_004, PRIN 20074TJ3ZB_005]
- European Molecular Biology Laboratory (EMBL)
Ask authors/readers for more resources
Polarized Fe K-edge X-ray absorption near-edge structure (XANES) spectra of murine carbonmonoxy-neuroglobin (NgbCO) single crystals have been collected and compared with a number of derivatives of sperm whale myoglobin (Mb), that is, the nitrosyl (MbNO) and deoxy (Mb) derivatives, the previously reported cyanomet (MbCN) and carbonmonoxy (MbCO) derivatives, and the cryogenic photoproduct of MbCO (Mb center dot CO). The single crystals under study exhibit a strong XANES angular dichroism which allows the heme geometry of each sample to be analyzed with extremely high accuracy via the full multiple scattering (MS) approach. The results of two alternative methods to undergo the MS analysis have been compared with high resolution X-ray diffraction (XRD) data and with X-ray absorption spectroscopy (XAS) data in solution. As a result of the present analysis, the Fe-heme Structure in solution and in the cryo-trapped NgbCO single crystal (which cracks at room temperature) are the same. Accordingly, the residual energy involved in the protein relaxation responsible of crystal cracking at room temperature alter CO binding does not reside in the helm pocket. A combined approach (polarized XANES and XRD) is suggested to be applied on the same single crystals of metalloproteins at opportunely equipped synchrotron beamlines.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available