Infrared Difference Spectroscopy of Proteins: From Bands to Bonds
- 23 March 2020
- journal article
- review article
- Published by American Chemical Society (ACS) in Chemical Reviews
- Vol. 120 (7), 3466-3576
- https://doi.org/10.1021/acs.chemrev.9b00449
Abstract
Infrared difference spectroscopy probes vibrational changes of proteins upon their perturbation. Compared with other spectroscopic methods, it stands out by its sensitivity to the protonation state, H-bonding, and the conformation of different groups in proteins, including the peptide backbone, amino acid side chains, internal water molecules, or cofactors. In particular, the detection of protonation and H-bonding changes in a time-resolved manner, not easily obtained by other techniques, is one of the most successful applications of IR difference spectroscopy. The present review deals with the use of perturbations designed to specifically change the protein between two (or more) functionally relevant states, a strategy often referred to as reaction-induced IR difference spectroscopy. In the first half of this contribution, I review the technique of reaction-induced IR difference spectroscopy of proteins, with special emphasis given to the preparation of suitable samples and their characterization, strategies for the perturbation of proteins, and methodologies for time-resolved measurements (from nanoseconds to minutes). The second half of this contribution focuses on the spectral interpretation. It starts by reviewing how changes in H-bonding, medium polarity, and vibrational coupling affect vibrational frequencies, intensities, and bandwidths. It is followed by band assignments, a crucial aspect mostly performed with the help of isotopic labeling and site-directed mutagenesis, and complemented by integration and interpretation of the results in the context of the studied protein, an aspect increasingly supported by spectral calculations. Selected examples from the literature, predominately but not exclusively from retinal proteins, are used to illustrate the topics covered in this review.Keywords
Funding Information
- Generalitat Valenciana (Prometeu/2019/066)
- Ministry of Science, Innovation and Universities (BFU2016-768050-P, BFU2017-91559-EXP, RYC-2013-13114)
This publication has 531 references indexed in Scilit:
- H/D Isotope Effects in Hydrogen Bonded SystemsMolecules, 2013
- Surface‐Attached Polyhistidine‐Tag Proteins Characterized by FTIR Difference SpectroscopyChemphyschem, 2012
- SEIRA Spectroscopy on a Membrane Receptor Monolayer Using Lipoprotein Particles as CarriersBiophysical Journal, 2010
- Structural snapshots of conformational changes in a seven-helix membrane protein: lessons from bacteriorhodopsinCurrent Opinion in Structural Biology, 2009
- Ultrafast transient absorption spectroscopy: principles and application to photosynthetic systemsPhotosynthesis Research, 2009
- Time-resolved flow-flash FT-IR difference spectroscopy: the kinetics of CO photodissociation from myoglobin revisitedAnalytical and Bioanalytical Chemistry, 2009
- Efforts Toward the Direct Experimental Characterization of Enzyme Microenvironments: Tyrosine100 in Dihydrofolate ReductaseAngewandte Chemie, 2009
- Time-Resolved Fourier Transform Infrared Study on Photoadduct Formation and Secondary Structural Changes within the Phototropin LOV DomainBiophysical Journal, 2009
- Synergy within structural biology of single crystal optical spectroscopy and X-ray crystallographyCurrent Opinion in Structural Biology, 2007
- Biochemical applications of surface-enhanced infrared absorption spectroscopyAnalytical and Bioanalytical Chemistry, 2007