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Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy
Published on: June 27, 2014
THE STRUCTURE OF THE ULTRAVIOLET ABSORPTION SPECTRA OF CERTAIN PROTEINS AND AMINO ACIDS.
C B Coulter1, F M Stone, E A Kabat
1Delamar Institute of Public Health, College of Physicians and Surgeons, Columbia University, New York.
The Journal of General Physiology
|October 30, 2009
Summary
Protein absorption spectra reveal unique configurations due to amino acid bands. These characteristic spectral fingerprints can help differentiate between various proteins, including antibodies.
Area of Science:
- Biochemistry
- Spectroscopy
- Protein Analysis
Background:
- Proteins exhibit complex absorption spectra in the 2500-3000 Angstrom range.
- The specific configuration of absorption curves varies between different proteins.
- Amino acids like tryptophan, tyrosine, and phenylalanine have distinct spectral bands.
Purpose of the Study:
- To analyze the absorption spectra of various proteins in the ultraviolet region.
- To identify the origin of characteristic spectral bands in proteins.
- To compare the spectral properties of proteins and specific amino acids.
Main Methods:
- Absorption spectroscopy was used to examine proteins in the 2500-3000 Angstrom range.
- Spectral data of proteins were compared with those of tryptophan, tyrosine, and phenylalanine.
- The absorption spectrum of Pneumococcus Type I antibody was analyzed and compared to normal pseudoglobulin.
Main Results:
- Protein absorption spectra in the 2500-3000 Angstrom region show 6-9 narrow bands.
- These bands closely match the spectral positions of tryptophan, tyrosine, and phenylalanine.
- Protein bands are typically shifted 10-35 Angstroms toward longer wavelengths compared to free amino acids.
- Pneumococcus Type I antibody exhibits a spectrum similar to, yet distinct from, normal pseudoglobulin.
Conclusions:
- The characteristic absorption spectra of proteins are attributed to the presence of tryptophan, tyrosine, and phenylalanine.
- Spectral analysis provides a method for differentiating proteins based on their amino acid composition.
- Ultraviolet absorption spectroscopy is a valuable tool for protein characterization and identification.
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