Biological applications of resonance Raman spectroscopy: haem proteins

Abstract

Resonance Raman spectroscopy involves laser excitation within an absorption band of the sample. Certain vibrational modes, those which couple to the electronic transition, exhibit greatly increased Raman scattering in the resulting spectrum. Sensitivity approaches that of absorption spectrophotometry, while the high resolution characteristic of vibrational spectroscopy is preserved, even in solution at room temperature. If the resonant electronic transition is associated with a site of biological activity, then the technique offers a sensitive probe for structural features of the site. Haem proteins afford particularly informative resonance Raman spectra, with a rich assortment of porphyrin ring vibrations, which can be classified and analysed via their symmetry properties. Certain of these frequencies are sensitive to the structural concomitants of spin- and oxidation-state changes of the haem group. These can be used to monitor the structural consequences of ligation or electron transfer in haem proteins.

Vibrational dynamics of biological molecules: Multi-quantum contributions

“…Evaluation of the angular average (k^⋅ e jα ) 2 for a randomly oriented sample, such as the polycrystalline powder considered here, reveals that the "recoil fraction"…”

“…Site-selective vibrational spectroscopies [2][3][4][5] have proven to be particularly revealing probes of the structure, dynamics and reactivity of protein active sites. Nuclear resonance vibrational spectroscopy (NRVS) is a relatively new technique that takes advantage of remarkable properties of synchrotron radiation, including time-pulsed structure, tunability, narrow bandwidth, and high brilliance, to reveal the complete vibrational spectrum of a probe nucleus.…”

Potential and limits of Raman spectroscopy for carotenoid detection in microorganisms: implications for astrobiology

“…For carotenoid work, advantageous enhancement of spectroscopic features can be obtained by employing Resonance Raman microspectrometry. For biological molecules absorbing light in the visible portion of the electromagnetic spectrum, new possibilities were discovered for Raman spectroscopy using the resonance Raman effect [10]. Tuning the excitation wavelength to the electronic absorption spectrum can produce selective enhancement of certain Raman bands [10,11].…”

Vibrational spectroscopic study of the interaction of metal ions with diethyl phosphate, a model for biological systems

“…Vibrational spectroscopy, particularly Raman spectroscopy, has been used extensively for the study of nucleic acids (5)(6)(7)(8). The symmetric stretching vibration of the PO; groups gives a moderately strong,and sharp band near 1090 cm-' in the Raman spectrum of DNA.…”