6533b7d5fe1ef96bd126456d
RESEARCH PRODUCT
Photosensibilisierte Oxidation von Lysozym bei Verschiedenen Wellenlängen
S. RisiK. DoseE. Silvasubject
Radiationdigestive oral and skin physiologyBiophysicsCystineTryptophanfood and beveragesPhotochemistryeye diseasesstomatognathic diseaseschemistry.chemical_compoundchemistryRose bengalsense organsIrradiationLysozymeMethylene blueHistidineGeneral Environmental ScienceVisible spectrumdescription
The photooxidation of lysozyme in the presence of methylene blue, riboflavine, and bengal rose at differentpH values and wavelengths was studied. Monochromatic irradiation at shorter wavelengths (345 and 365 nm) is - in contrast to visible light - characterized by higher energy yields and lower oxygen consumption. This behavior suggests that the mechanism of photooxidation depends on the wavelength. The specific destruction of amino acid residues is also wavelength-dependent. Using visible light of 448 and 621 nm for riboflavine and methylene blue, respectively, we have confirmed the selective destruction of histidine and tryptophan atpH 7,0. The energy yield for the destruction of tryptophan in lysozyme is much larger than in other proteins. This result is likely related to the exposed location of tryptophan-62 and tryptophan-63 in lysozyme, which is also evident from the kinetic analysis of the corresponding dose-effect relationships. If lysozyme is irradiated with light of 365 nm in the presence of riboflavine only cystine, tyrosine, and methionine are destroyed.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 1974-06-01 | Radiation and Environmental Biophysics |