Resonance Raman spectroscopy dichroism

The heme moiety provides de novo designed heme proteins with an intrinsic and spectroscopically rich probe. The interaction of the amide bonds of the peptide or protein with the heme macrocycle provides for an induced circular dichroism spectrum indicative of protein-cofactor interactions. The strong optical properties of the heme macrocycle also make it suitable for resonance Raman spectroscopy. Aside from the heme macrocycle, the encapsulated metal ion itself provides a spectroscopic probe into its electronic structure via EPR spectroscopy and electrochemistry. These spectroscopic and electrochemical tools provide a strong quantitative base for the detailed evaluation of the relative successes of de novo heme proteins. 

Probing Metalloproteins Electronic absorption spectroscopy of copper proteins, 226, 1 electronic absorption spectroscopy of nonheme iron proteins, 226, 33 cobalt as probe and label of proteins, 226, 52 biochemical and spectroscopic probes of mercury(ii) coordination environments in proteins, 226, 71 low-temperature optical spectroscopy metalloprotein structure and dynamics, 226, 97 nanosecond transient absorption spectroscopy, 226, 119 nanosecond time-resolved absorption and polarization dichroism spectroscopies, 226, 147 real-time spectroscopic techniques for probing conformational dynamics of heme proteins, 226, 177 variable-temperature magnetic circular dichroism, 226, 199 linear dichroism, 226, 232 infrared spectroscopy, 226, 259 Fourier transform infrared spectroscopy, 226, 289 infrared circular dichroism, 226, 306 Raman and resonance Raman spectroscopy, 226, 319 protein structure from ultraviolet resonance Raman spectroscopy, 226, 374 single-crystal micro-Raman spectroscopy, 226, 397 nanosecond time-resolved resonance Raman spectroscopy, 226, 409 techniques for obtaining resonance Raman spectra of metalloproteins, 226, 431 Raman optical activity, 226, 470 surface-enhanced resonance Raman scattering, 226, 482 luminescence... 

A range of techniques, i.e. Mossbauer, magnetic circular dichroism, ESR and resonance Raman spectroscopy together with EXAFS results on two 3Fe proteins, have been applied to the problem of the structure of these three-iron clusters. These results have been comprehensively and critically reviewed.741... 

Online coupling of surface-enhanced resonance Raman spectroscopy and IPC proved valuable for the identification of basic dyes [124]. Circular dichroism spectroscopy is an extraordinary technique for selective detection of compounds possessing optically active adsorption bands and was successfully coupled to IPC of steroids [125]. Table 12.4. summarizes the most important features and parameters to be compared when selecting a detection mode for an IPC application. 

Other Degraded Carotenoids Carotenoid-Protein Complexes Physical Methods Separation and Assay N.M.R. Spectroscopy Electronic Absorption Spectroscopy Resonance Raman Spectroscopy X-Ray Structures Linear Dichroism... 

Mascharak et al. 63) have prepared a structural BLM model PMAH containing pyrimidine, imidazole, and primary and secondary amine building blocks. The iron -PMAH complex was studied by X-ray absorption, magnetic circular dichroism, and resonance Raman spectroscopy 63). This Fe-BLM model exhibits a five-coordinate, square pyramidal geometry in the solid state and a distorted octahedral geometry in solution with a solvent molecule at the sixth position. Similar spectral features have been found for Fe -BLM. This PMAH-Fe" complex binds O2 to generate PMAH-Fe "-OOH, a low-spin hydroperoxo-iron(III) complex 64) able to promote the lipid peroxidation as BLM 65). 

This chapter focuses on the extraction and handling of retinoids and carotenoids, their separation by various chromatographic techniques, and their detection and quantitation, primarily by absorption spectrophotometry, fluorescence, and mass spectrometry. A variety of other methods exist for their identification and characterization, including circular dichroism (333), infrared spectroscopy (334), resonance Raman spectroscopy (335), NMR spectroscopy (336), and x-ray crystallography (337). Although some of these procedures require substantial amounts of a retinoid or a carotenoid in an essentially pure form for study, others, such as resonance Raman spectroscopy, are extremely sensitive and can be used to detect the localization of carotenoids in single cells (338,339). 

Materials characterization techniques, ie, atomic and molecular identification and analysis, ate discussed ia articles the tides of which, for the most part, are descriptive of the analytical method. For example, both iaftared (it) and near iaftared analysis (nira) are described ia Infrared and raman SPECTROSCOPY. Nucleai magaetic resoaance (nmr) and electron spia resonance (esr) are discussed ia Magnetic spin resonance. Ultraviolet (uv) and visible (vis), absorption and emission, as well as Raman spectroscopy, circular dichroism (cd), etc are discussed ia Spectroscopy (see also Chemiluminescence Electho-analytical techniques It unoassay Mass specthot thy Microscopy Microwave technology Plasma technology and X-ray technology). 

Aside from the direct techniques of X-ray or electron diffraction, the major possible routes to knowledge of three-dimensional protein structure are prediction from the amino acid sequence and analysis of spectroscopic measurements such as circular dichroism, laser Raman spectroscopy, and nuclear magnetic resonance. With the large data base now available of known three-dimensional protein structures, all of these approaches are making considerable progress, and it seems possible that within a few years some combination of noncrystallo-graphic techniques may be capable of correctly determining new protein structures. Because the problem is inherently quite difficult, it will undoubtedly be essential to make the best possible use of all hints available from the known structures. 

Before the availability of a high-resolution structure of P. aeruginosa CCP, the properties and environments of the two hemes had been probed using a range of solution spectroscopies. These include electron paramagnetic resonance (EPR) (51, 57, 58, 61), resonance Raman (59), circular dichroism (CD) 71, 72), MCD 58, 61, 73, 74). Until the demonstration by Ellfolk and colleagues that it is the mixed-valence form of the... 

The discussion of activity from X-ray data in conjunction with kinetic data is also difficult because, apart from considerations of dynamics, these techniques do not provide the essential knowledge about the energy states of given atoms or groups. It is necessary to inspect the electronic structure of at least certain regions of the protein. Methods exist for this inspection, and these include electron paramagnetic resonance, ultraviolet, circular dichroism, Raman and Mossbauer spectroscopies. The full understanding of activity can only come when the information derived from all available methods is assimilated and rationalized. 

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