Photoinactivation of cells studied by 31P-NMR
31P-NMR techniques allow the continuous, non-destructive measurements of phosphorous compounds in intact cells. Immediate effects of photodynamic treatment and photosensitization processes can be mapped [2,6]. 31P-NMR also gives information about changes in the pH gradient across membranes and indirectly about ion pumping mechanisms controlling proton fluxes . We have studied the bacterium Propionibacterium acnes, (P. acnes) which produces large amounts of endogenous porphyrins taking part in photosensitization . Externally applied HpD is effective in increasing the photosensitivity . In the present short report we would like to present some new experimental results where 31P-NMR has been used to analyse photodynamic reactions of red light and HpD treatment.
KeywordsNADH Porphyrin Saccharomyces Acne Polyphosphates
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