Open AccessX‐ray spectroscopy and X‐ray diffraction at wavelengths near the K ‐absorption edge of phosphorus
Author(s) -
Biou Valérie,
Kahn Richard,
Mas Corinne,
Bösecke Peter,
Bois JeanMarie,
Brandolin Gérard,
Nauton Lionel,
Nury Hugues,
PebayPeyroula Eva,
Vicat Jean,
Stuhrmann Heinrich
Publication year - 2005
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s0909049505009222
Subject(s) - absorption edge , diffraction , absorption (acoustics) , absorption spectroscopy , chemistry , neutron diffraction , selected area diffraction , crystallography , x ray crystallography , analytical chemistry (journal) , molecular physics , materials science , optics , crystal structure , physics , band gap , optoelectronics , chromatography
Phosphorus is an abundant element in living organisms. It is traceable by its X‐ray absorption spectrum which shows a strong white line at its K ‐edge, comparable with that observed for the L III edges of rare earth ions. With purple membrane, the variation of the imaginary part of the anomalous dispersion of phosphorus is found to be close to 20 anomalous electron units. Anomalous diffraction experiments at wavelengths near the K ‐absorption edge of phosphorus confirm this result. The spatial distribution of lipids derived from anomalous diffraction agrees with earlier results from neutron diffraction. Test experiments on single crystals of the carrier protein using 5.76 Å photons gave a first low‐resolution diffraction pattern. Various techniques of crystal mounting were attempted. In addition, fluorescence measurements on a solution of threonine synthase appear to hint at a change of the phosphate environment of the cofactor upon activator binding.