TY - JOUR
T1 - The calf gamma crystallins-A Raman spectroscopic study
AU - Pande, Jayanti
AU - McDermott, Martin J.
AU - Callender, Robert H.
AU - Spector, Abraham
N1 - Funding Information:
This work was supported by grants GM35183 and EYO 3 142 from the National Institutes of Health to R. C. and grants from the National Eye Institute to A.S. We thank Elaine Bluberg for expert secretarial assistance.
PY - 1991/2
Y1 - 1991/2
N2 - The solution structures of the four major components of bovine lens γ-crystallin, γs, γII, γIII and γIV are compared using Raman spectroscopy. The spectral region sensitive to the vibrational frequencies of aromatic and sulfur containing residues and to the backbone skeletal stretching modes (500-1000 cm-1), and that reflecting secondary structure (1000-1700 cm-1) are strikingly similar in all four γ-crystallin fractions. These similarities are indicative of the dominant anti-parallel β sheet structure common to all the γ-crystallins. A comparison of the ratios of the Raman intensities at 850 cm-1 and 830 cm-1 ( I850 I830), an empirical measure of the degree of hydrogen bonding of phenolic hydroxyl groups, suggests that the tyrosine residues in all the γ-crystallin fractions are moderately hydrogen bonded. Distinct differences in the solution structures of the γ-crystallins were observed in the higher energy end of the vibrational Raman spectra. The sulfhydryl stretching frequencies for the γ-crystallins exhibit complex splitting patterns in the 2500-2600 cm-1 region. These patterns are due to the competing effects of hydrogen bonding and S-π interactions with neighboring aromatic residues. All five proteins exhibit multiple, but distinct, thiol frequencies, suggesting that the microenvironments of the cysteine residues in these proteins are significantly different.
AB - The solution structures of the four major components of bovine lens γ-crystallin, γs, γII, γIII and γIV are compared using Raman spectroscopy. The spectral region sensitive to the vibrational frequencies of aromatic and sulfur containing residues and to the backbone skeletal stretching modes (500-1000 cm-1), and that reflecting secondary structure (1000-1700 cm-1) are strikingly similar in all four γ-crystallin fractions. These similarities are indicative of the dominant anti-parallel β sheet structure common to all the γ-crystallins. A comparison of the ratios of the Raman intensities at 850 cm-1 and 830 cm-1 ( I850 I830), an empirical measure of the degree of hydrogen bonding of phenolic hydroxyl groups, suggests that the tyrosine residues in all the γ-crystallin fractions are moderately hydrogen bonded. Distinct differences in the solution structures of the γ-crystallins were observed in the higher energy end of the vibrational Raman spectra. The sulfhydryl stretching frequencies for the γ-crystallins exhibit complex splitting patterns in the 2500-2600 cm-1 region. These patterns are due to the competing effects of hydrogen bonding and S-π interactions with neighboring aromatic residues. All five proteins exhibit multiple, but distinct, thiol frequencies, suggesting that the microenvironments of the cysteine residues in these proteins are significantly different.
KW - Raman spectroscopy
KW - gamma crystallins
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U2 - 10.1016/0014-4835(91)90258-G
DO - 10.1016/0014-4835(91)90258-G
M3 - Article
C2 - 2013301
AN - SCOPUS:0026081408
SN - 0014-4835
VL - 52
SP - 193
EP - 197
JO - Experimental Eye Research
JF - Experimental Eye Research
IS - 2
ER -