Ultraviolet resonance Raman excitation profiles of tyrosine:  dependence of Raman cross sections on excited-state intermediates

Ludwig, Michael; Asher, Sanford A.

doi:10.1021/ja00212a004

Cited by 85 publications

(95 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Since the power density of the excitation laser light is sufficiently low, this intensity difference would not be caused by saturation effects (Ludwig & Asher, 1988;Teraoka et al, 1990). It is probably due to the red shift of the Bb band ( -220 nm) in the protein as deduced by Toyama et al (1993), since the intensity ratio of the W1 and W3 bands (R = Iwl/Zws), which has been pointedout to besensitive to the position of the Bb band (Harada et al, 1990), is also larger for the amino acid solution (R = 3.0 f 0.2) than for the protein solution (2.6 f 0.2 for spectrum A and 2.5 f 0.2 for spectrum B).…”

Section: Raman Shift /Em''mentioning

confidence: 99%

Ultraviolet resonance Raman spectra of pea intact, large, and small phytochromes: Differences in molecular topography of the red- and far-red-absorbing forms

Mizutani¹,

Tokutomi²,

Kaminaka³

et al. 1993

Biochemistry

View full text Add to dashboard Cite

Ultraviolet resonance Raman (UV RR) spectra excited at 244 nm were observed for pea intact, large, and small phytochromes at pH 7.8. Raman bands assignable to Trp residues dominated the UV RR spectra. The intensity ratios of Trp W7 doublet bands, I(1358)/I(1342), of all three phytochromes in the red light-absorbing form (Pr) were almost the same as that of an aqueous Trp solution, indicating that most of the six and four Trp residues in the 59-kDa chromophoric and the C-terminal 59-kDa nonchromophoric domains, respectively, reside in hydrophilic microenvironments in Pr. This ratio increased under red light illumination, where photoequilibria are attained between Pr and the far-red-absorbing form (Pfr) for intact and small phytochromes and among Pr, a bleached intermediate (Ibl), and Pfr for large phytochromes. The increase of the intensity ratio was most prominent for small phytochromes. These observations suggest that the microenvironments around some Trp residues become more hydrophobic due to conformational changes induced by phototransformation from Pr to Ibl and that the hydrophobicity increase occurs mainly in the chromophoric domain. Among the six Trp residues in the chromophoric domain, Trp365 and Trp567 are likely candidates for those involved in this hydrophobicity increase. The intensity distribution of the amide I band shows little beta-sheet in both Pr and Pfr of the intact, large, and small phytochromes and indicates that alpha-helices and nonregular structure are less populated in the chromophoric domain than in the N-terminal 6-kDa segment and the C-terminal nonchromophoric domain.

show abstract

Section: Raman Shift /Em''mentioning

confidence: 99%

Ultraviolet resonance Raman spectra of pea intact, large, and small phytochromes: Differences in molecular topography of the red- and far-red-absorbing forms

Mizutani¹,

Tokutomi²,

Kaminaka³

et al. 1993

Biochemistry

View full text Add to dashboard Cite

show abstract

“…It should also be noted that the Tyr Raman doublet intensity ratio was being used during the last decades for analyzing the hydrophilic (or hydrophobic) environment of Tyr (and tyrosinate), by means of either classical or Ultraviolet (UV)-resonance Raman spectra. [13,[27][28][29][30][31][32][33][34][35] One can understand that an accurate Scheme 1. Nomenclature and main conformational angles of the model compounds considered in the theoretical calculations.…”

Section: Introductionmentioning

confidence: 99%

All characteristic Raman markers of tyrosine and tyrosinate originate from phenol ring fundamental vibrations

Hernández

Coïc

Pflüger

et al. 2015

J Raman Spectroscopy

101

View full text Add to dashboard Cite

Raman data collected from free amino acid and peptide chains permit assignment of the seven markers located at approximately 1616, 1606, 1210, 1178, 850, 830, and 643 cm À1 to tyrosine. The effects induced by labile hydrogen deuteration, temperature, concentration, and protonation-deprotonation on these Raman markers were analyzed. Following closely a recent multiconformational analysis on phenylalanine, we could confirm the predominance of gauche -/gauche -rotamers with respect to the side chain χ 1 /χ 2 torsion angles in both tyrosine and tyrosinate. Calculated Raman spectra, based on the consideration of both implicit and explicit hydration models, have revealed the effect of hydrogen bonding of water molecules to the phenol ring hydroxyl group of tyrosine. A special attention has been paid to the 850/830 cm À1 tyrosine doublet, for which no intensity ratio inversion could be remarked when the phenol hydroxyl group acts as a hydrogen bond donor or acceptor. On the contrary, this intensity ratio appeared to be strongly dependent on the hydrophobic/hydrophilic balance of the interactions, in which the phenol ring is involved. Based on the present theoretical calculations, the components of the tyrosine doublet might originate from two independent fundamental modes of the phenol ring: one with an in-plane character and the other with an out-ofplane character. As a consequence, the widely spread Fermi resonance-based description of the tyrosine doublet appears to be unjustified. The latter interpretation simply results from the insufficiencies of the simple model compound used at that time for analyzing the vibrational features of a more complex molecular system such as tyrosine.

show abstract

“…2), and excitation at ~240 nm produces selective resonance enhancement of the Raman bands of Tyr -. 7,8 The deprotonation also causes shifts of the Y8a, Y8b, and Y9a bands at 1617, 1601, and 1180 cm -1 (Fig. 3b) by about -15, -40, and -5 cm -1 , respectively.…”

Section: ·1 Protonation/deprotonationmentioning

confidence: 98%

“…3b) by about -15, -40, and -5 cm -1 , respectively. 6,8 The imidazole side chain of His carries two nitrogen atoms, Nτ and Nπ (Fig. 3d).…”

Section: ·1 Protonation/deprotonationmentioning

confidence: 99%

UV Raman Markers for Structural Analysis of Aromatic Side Chains in Proteins

Takeuchi

2011

ANAL. SCI.

View full text Add to dashboard Cite

UV Raman spectroscopy is a powerful tool for investigating the structures and interactions of the aromatic side chains of Phe, Tyr, Trp, and His in proteins. This is because Raman bands of aromatic ring vibrations are selectively enhanced with UV excitation, and intensities and wavenumbers of Raman bands sensitively reflect structures and interactions. Interpretation of protein Raman spectra is greatly assisted by using empirical correlations between spectra and structure. Many Raman bands of aromatic side chains have been proposed to be useful as markers of structures and interactions on the basis of empirical correlations. This article reviews the usefulness and limitations of the Raman markers for protonation/deprotonation, conformation, metal coordination, environmental polarity, hydrogen bonding, hydrophobic interaction, and cation-π interaction of the aromatic side chains. The utility of Raman markers is demonstrated through an application to the structural analysis of a membrane-bound proton channel protein.

show abstract

Ultraviolet resonance Raman excitation profiles of tyrosine: dependence of Raman cross sections on excited-state intermediates

Cited by 85 publications

References 1 publication

Ultraviolet resonance Raman spectra of pea intact, large, and small phytochromes: Differences in molecular topography of the red- and far-red-absorbing forms

Ultraviolet resonance Raman spectra of pea intact, large, and small phytochromes: Differences in molecular topography of the red- and far-red-absorbing forms

All characteristic Raman markers of tyrosine and tyrosinate originate from phenol ring fundamental vibrations

UV Raman Markers for Structural Analysis of Aromatic Side Chains in Proteins

Contact Info

Product

Resources

About