A Raman spectroscopic study of hen egg yolk phosvitin: structures in solution and in the solid state
- 1 May 1986
- journal article
- research article
- Published by American Chemical Society (ACS) in Biochemistry
- Vol. 25 (10), 2792-2798
- https://doi.org/10.1021/bi00358a009
Abstract
Laser Raman spectroscopy has been employed to study the structure of the hen egg yolk protein phosvitin in H2O and D2O solutions at neutral and acidic pH (pD) and in the solid state. The Raman data indicate an unusual conformation for phosvitin in neutral aqueous solution, which is deficient in both .alpha.-helix and conventional .beta.-sheet conformations. This unusual pH 7 structure is, however, largely converted to a .beta.-sheet conformation in strongly acidic media (pH < 2). .beta.-Sheet is also the predominant secondary structure for phosvitin in the solid state, obtained by lyophilization of the protein from aqueous solution at neutral pH. The imidazolium rings of histidyl residues remain significantly protonated near neutrality, which suggests substantial elevation of the pK for imidazolium ring ionizations of phosvitin in aqueous solution. This may result from extensive ion-pair interactions involving positively charged histidines and negatively charged phosphoserines, which are prevalent in the phosvitin sequence. The present results suggest that antiparallel .beta.-sheets may not be the secondary structure most characteristic of native phosvitin (physiological pH), even though .beta.-sheet is the predominant conformation for phosvitin in acidic solutions (pH 1.5) and in the lyophilized solid. Phosvitin appears to be the first protein for which the major component to the Raman amide I band is centered near 1685 cm-1, which is 10-40 cm-1 higher than proteins heretofore examined in aqueous solution by Raman spectroscopy.This publication has 18 references indexed in Scilit:
- Raman spectroscopy and deuterium exchange of the filamentous phage fdBiochimica et Biophysica Acta (BBA) - Protein Structure and Molecular Enzymology, 1984
- Estimation of protein secondary structure from the laser Raman amide I spectrumJournal of Molecular Biology, 1983
- Structure similarity, difference and variability in the filamentous viruses fd, If1, IKe, Pf1 and XfJournal of Molecular Biology, 1983
- Structure of hen phosvitin: a phosphorus-31 NMR, proton NMR, and laser photochemically induced dynamic nuclear polarization proton NMR studyBiochemistry, 1983
- Raman spectroscopic study of the interaction between sulfate anion and an imidazolium ring in ribonuclease ABiochemistry, 1982
- Vibrational analysis of peptides, polypeptides, and proteins. V. Normal vibrations of β‐turnsBiopolymers, 1980
- Raman spectra of polypeptides containing L‐histidine residues and tautomerism of imidazole side chainBiopolymers, 1979
- Analysis of the accuracy and implications of simple methods for predicting the secondary structure of globular proteinsJournal of Molecular Biology, 1978
- The Circular Dichroism of PhosvitinJournal of Biological Chemistry, 1967
- PREPARATION AND CHARACTERIZATION OF PHOSVITIN FROM HEN EGG YOLKCanadian Journal of Biochemistry and Physiology, 1958