Protein Raman scattering

The ROA spectra of partially unfolded denatured hen lysozyme and bovine ribonuclease A, prepared by reducing all the disulfide bonds and keeping the sample at low pH, together with the ROA spectra of the corresponding native proteins, are displayed in Figure 5. As pointed out in Section II,B, the short time scale of the Raman scattering event means that the ROA spectrum of a disordered system is a superposition of snapshot ROA spectra from all the distinct conformations present at equilibrium. Because of the reduced ROA intensities and large... 

Schellenberg P, Johnson E, Esposito AP, Reid PJ, Parson WW (2001) Resonance Raman scattering by the green fluorescent protein and an analogue of its chromophore. J Phys Chem B 105 5316-5322... 

C.R. Yonzon, C.L. Haynes, X. Zhang, J.T. Walsh Jr. and R.P. Van Duyne, A glucose biosensor based on surface-enhanced Raman scattering improved partition layer, temporal stability, reversibility, and resistance to serum protein interference, Anal. Chem., 76(1) (2004) 78-85. 

Figure 3. Resonance Raman spectrum of purple acid phosphatase. Protein (5 mM) maintained at 5 C In a glass Dewar and probed with 514.5 nm excitation (within the 560 nm phenolate + Fe(III) CT band, e = 4,000 cm" M The broad, underlying feature from 400-550 cm"1 Is due to Raman scattering from glass. (Reproduced from Ref. 14. Copyright 1987 American Chemical Society.)...

Resonance Raman scattering provides a valuable method of determining the state of axial ligation in nickel-reconstituted heme proteins and Ni-porphyrin complexes. A pattern of shifts in the Raman coresize and oxidation-state marker lines can be used to monitor changes in axial coordination. The shifts in the core-size lines (e.g. indicate an expansion of the core from about 1.96 A for the 4-coordinate Ni porphyrin to 2.04 A for the 6-coordinate species,... 

The metaiioporphyrins form a diverse class of molecules exhibiting complex and varied photochemistries. Until recently time-resolved absorption and fluorescence spectroscopies were the only methods used to study metailoporphyrln excited state relaxation in a submicrosecond regime. In this paper we present the first picosecond time-resolved resonance Raman spectra of excited state metaiioporphyrins outside of a protein matrix. The inherent molecular specificity of resonance Raman scattering provides for a direct probe of bond strengths, geometries, and ligation states of photoexcited metaiioporphyrins. 

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... 

One can distinguish between methods in which absorption of the evanescent surface wave in different wavelength regions is measured (these are often called attenuated total reflection methods), and methods which use the evanescent wave to excite other, spectroscopic phenomena, like fluorescence and Raman scattering or light scattering. As the methods of conventional fluorescence spectroscopy have been shown to be exceptionally successful in studies of proteins and other biopolymers, their evanescent surface-sensitive counterparts will be reviewed first. 

Abstract Now an incisive probe of biomolecular structure, Raman optical activity (ROA) measures a small difference in Raman scattering from chiral molecules in right- and left-circularly polarized light. As ROA spectra measure vibrational optical activity, they contain highly informative band structures sensitive to the secondary and tertiary structures of proteins, nucleic acids, viruses and carbohydrates as well as the absolute configurations of small molecules. In this review we present a survey of recent studies on biomolecular structure and dynamics using ROA and also a discussion of future applications of this powerful new technique in biomedical research. 

The observations illustrate that inelastic and thermally activated tunnel channels may apply to metalloproteins and large transition metal complexes. The channels hold perspectives for mapping protein structure, adsorption and electronic function at metallic surfaces. One observation regarding the latter is, for example that the two electrode potentials can be varied in parallel, relative to a common reference electrode potential, at fixed bias potential. This is equivalent to taking the local redox level up or down relative to the Fermi levels (Fig. 5.6a). If both electrode potentials are shifted negatively, and the redox level is empty (oxidized), then the current at first rises. It reaches a maximum, convoluted with the bias potential between the two Fermi levels, and then drops as further potential variation takes the redox level below the Fermi level of the positively biased electrode. The relation between such current-voltage patterns and other three-level processes, such as molecular resonance Raman scattering [76], has been discussed [38]. 

In the future, we will see developments involving surface enhanced Raman scattering technologies in combination with AuNPs and waveguides as well as combinations of immobilized and solution-bom AuNPs and functional bridges in-between them. It can also be expected that applied medical research, namely the detection of antigens, enzymes, and proteins in body fluids, will benefit fi om the sensor developments with its extreme sensitivities. 

Vander Meulen and Ressler (1980) measured the near-lR spectra of proteins in aqueous solution and compared them with the spectra of protein films. Brown et al. (1983) reported multiple internal reflectance spectra of hydrated films of carbonmonoxy and oxy forms of hemoglobin. This work was extended by Findsen et al. (1986), who, using resonance Raman scattering, measured the effects of hydration on the equilibrium and dynamic properties of hemoglobin and its carbonmonoxy complex. There was a substantial effect of hydration on the CO vibration, but no significant effect on the vibrational properties of the heme protein. 

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