Recently, we have shown that multiple scattering (MS) theory, via the MXAN package, is able to reproduce the experimental X-ray absorption near edge structure (XANES) data of biological samples, in particular hemeproteins, from the rising edge up to similar to 150-200 eV above the edge. In the present work, we illustrate how XANES can be used either as an independent tool to provide bond-lengths and bond-angles for a metalloprotein active site in solution, or in combination with X-ray Diffraction for structural determinations of ligand binding geometry of the same diffracting protein crystal, providing atomic precision even for crystallographic structures solved at > 1.2 angstrom resolution. At low temperature, XANES can be applied to provide the Fe-heme structure of trapped intermediate conformations; of fight triggered processes, and some aspects of the ligand binding dynamics. Very recently, XANES difference spectra have been analyzed to provide the Fe-heme structure of multiple intermediates of carbonmonoxy-myoglobin, obtained under different photolysis protocols in solution state.
Hemeproteins: Recent Advances in Quantitative XANES Analysis / A., Arcovito; M., Benfatto; S., DELLA LONGA; D'Angelo, Paola. - In: AIP CONFERENCE PROCEEDINGS. - ISSN 0094-243X. - STAMPA. - 882:(2007), pp. 306-310. (Intervento presentato al convegno X-RAY ABSORPTION FINE STRUCTURE - XAFS13: 13th International Conference tenutosi a Stanford, CA; United States nel 9 July 2006 through 14 July 2006) [10.1063/1.2644508].
Hemeproteins: Recent Advances in Quantitative XANES Analysis
D'ANGELO, Paola
2007
Abstract
Recently, we have shown that multiple scattering (MS) theory, via the MXAN package, is able to reproduce the experimental X-ray absorption near edge structure (XANES) data of biological samples, in particular hemeproteins, from the rising edge up to similar to 150-200 eV above the edge. In the present work, we illustrate how XANES can be used either as an independent tool to provide bond-lengths and bond-angles for a metalloprotein active site in solution, or in combination with X-ray Diffraction for structural determinations of ligand binding geometry of the same diffracting protein crystal, providing atomic precision even for crystallographic structures solved at > 1.2 angstrom resolution. At low temperature, XANES can be applied to provide the Fe-heme structure of trapped intermediate conformations; of fight triggered processes, and some aspects of the ligand binding dynamics. Very recently, XANES difference spectra have been analyzed to provide the Fe-heme structure of multiple intermediates of carbonmonoxy-myoglobin, obtained under different photolysis protocols in solution state.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
