This method was able to detect protein backbone conformational changes because of the hypoand hyperchromic interactions that, for example, result from peptide bond excitonic interactions in the α-helix conformation.
X-ray Crystallography is the gold standard technique for determining static protein structures (from protein crystals), and much of the insight into protein science has resulted from the many incisive stationary x-ray structures.
The UVRR light is collected and dispersed by a spectrograph and the spectrum is detected by a CCD detector.
Non kinetic Raman measurements of static structure are best measured by using CW lasers that avoid nonlinear optical and thermal processes that can induce sample degradation.
UVRR excitation of Mb at 415 nm in the strong heme Soret absorption band, results in an intense UVRR spectra which contains only the in-plane heme ring vibrations.
Thus, tuning the UVRR excitation wavelengths, allows the probing of different chromophoric segments of a macromolecule.
In this case the vibrational modes observed are particular vibrations whose motions couple to the driven electronic motion occurring in the electronic transition.
These incisive, quantitative glimpses into conformation can be combined with kinetic T-jump methodologies to monitor the dynamics of biomolecular conformational transitions.UV resonance Raman spectroscopy (UVRR) is a powerful method that has the requisite selectivity and sensitivity to incisively monitor biomolecular structure and dynamics in solution.In this perspective, we highlight applications of UVRR for studying peptide and protein structure and the dynamics of protein and peptide folding.The framework model propose the occurrence of funnel-shaped folding energy landscapes, where the native state is accessed via a strategically sloped energy landscape that funnel myriads of partially folded conformations towards the native folded state.Numerous experimental techniques are being applied to study protein folding.
Another advantage of deep UV Raman measurements is that there is no interference from molecular relaxed fluorescence.