Details

Autor(en) / Beteiligte

• Jockusch, Steffen
• Turro, Nicholas J.
• Banala, Srinivas
• Kräutler, Bernhard

Titel

Photochemical studies of a fluorescent chlorophyll catabolite–source of bright blue fluorescence in plant tissue and efficient sensitizer of singlet oxygen

Ist Teil von

• Photochemical & photobiological sciences, 2014-02, Vol.13 (2), p.407-411

Ort / Verlag

Cham: Springer International Publishing

Erscheinungsjahr

2014

Quelle

MEDLINE

Beschreibungen/Notizen

• Fluorescent chlorophyll catabolites (FCCs) are fleeting intermediates of chlorophyll breakdown, which is seen as an enzyme controlled detoxification process of the chlorophylls in plants. However, some plants accumulate large amounts of persistent FCCs, such as in senescent leaves and in peels of yellow bananas. The photophysical properties of such a persistent FCC (Me- s FCC) were investigated in detail. FCCs absorb in the near UV spectral region and show blue fluorescence (max at 437 nm). The Me- s FCC fluorescence had a quantum yield of 0.21 (lifetime 1.6 ns). Photoexcited Me- s FCC intersystem crosses into the triplet state (quantum yield 0.6) and generates efficiently singlet oxygen (quantum yield 0.59). The efficient generation of singlet oxygen makes fluorescent chlorophyll catabolites phototoxic, but might also be useful as a (stress) signal and for defense of the plant tissue against infection by pathogens.