Photosensitization of singlet oxygen formation by pterins and flavins. Time-resolved studies of oxygen phosphorescence under laser excitation.

Abstract

To elucidate the biochemical roles of singlet molecular oxygen (1(O2)) in the light-dependent reactions photosensitized by biological blue-light photoreceptors, time-resolved measurements of photosensitized 1O2 phosphorescence (1270 nm) were performed in air-saturated aqueous ((D2)O) solutions of pterins (2-amino-4-hydroxy-6,7-dimethylpteridine (DMP) and 2-amino-4-hydroxy-6-tetrahydroxybutyl-(D-arabo)pteridine (TOP)) and flavins (riboflavin and flavin mononucleotide (FMN)) under excitation with nitrogen laser (337.1 nm) pulses. The 1(O2) quantum yields were found to be 0.16, 0.20, 0.50, and 0.50 for DMP, TOP, riboflavin, and FMN, respectively. The data indicate that pterins and flavins are rather efficient photosensitizers of 1(O2) production that might be important for their photobiological functions.

• Authors: S Y Egorov, A A Krasnovsky Jr, M Y Bashtanov, E A Mironov, T A Ludnikova, M S Kritsky
• Journal: Biochemistry. Biokhimiia (Biochemistry (Mosc)) Vol. 64 Issue 10 Pg. 1117-21 (Oct 1999) ISSN: 0006-2979 [Print] United States
• PMID: 10561557 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Flavins
• Photosensitizing Agents
• Pterins
• Singlet Oxygen
• Oxygen

Topics

• Flavins (pharmacology)
• Lasers
• Luminescent Measurements
• Oxygen
• Photosensitizing Agents (pharmacology)
• Pterins (pharmacology)
• Singlet Oxygen
• Spectrum Analysis