Fourier transform infrared (FTIR) spectroscopy

Photosynthesis Research - Tập 101 - Trang 157-170 - 2009
Catherine Berthomieu1, Rainer Hienerwadel2
1CEA (Commissariat à l’ Energie Atomique), Laboratoire des Interactions Protéine Métal, DSV (Direction des Sciences du Vivant), Institut de Biologie Environnementale et Biotechnologie, Service de Biologie Végétale et Microbiologie Environnementales (DSV/iBEB/SBVME), CEA-Cadarache, UMR 6191 Centre National de la Recherche Scientifique (CNRS)-CEA (Commissariat à l’ Energie Atomique)-Université Aix-Marseille II, Saint Paul-lez-Durance Cedex, France
2Aix-Marseille Université, Laboratoire de Génétique et de Biophysique des Plantes, Faculté des Sciences de Luminy, Direction des Sciences du Vivant, Institut de Biologie Environnementale et Biotechnologie, Service de Biologie Végétale et Microbiologie Environnementales (DSV/iBEB/SBVME), UMR 6191 Centre National de la Recherche Scientifique (CNRS)-CEA (Commissariat à l’ Energie Atomique)-Université Aix-Marseille II, Marseille cedex 9, France

Tóm tắt

Fourier transform infrared (FTIR) spectroscopy probes the vibrational properties of amino acids and cofactors, which are sensitive to minute structural changes. The lack of specificity of this technique, on the one hand, permits us to probe directly the vibrational properties of almost all the cofactors, amino acid side chains, and of water molecules. On the other hand, we can use reaction-induced FTIR difference spectroscopy to select vibrations corresponding to single chemical groups involved in a specific reaction. Various strategies are used to identify the IR signatures of each residue of interest in the resulting reaction-induced FTIR difference spectra. (Specific) Isotope labeling, site-directed mutagenesis, hydrogen/deuterium exchange are often used to identify the chemical groups. Studies on model compounds and the increasing use of theoretical chemistry for normal modes calculations allow us to interpret the IR frequencies in terms of specific structural characteristics of the chemical group or molecule of interest. This review presents basics of FTIR spectroscopy technique and provides specific important structural and functional information obtained from the analysis of the data from the photosystems, using this method.

Tài liệu tham khảo

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