studia universitatis babeş-bolyai biologia 2

C. I. SICORA, M. DRĂGAN-BULARDA, I. VASS
F i g . 7 . The effect of 10 mM benzyl alcohol (BA) on luminescence emission during
visible light illumination of Synechocytis PCC 6803 strain containing
the luciferase construct under psbA 2 promoter.
Temperature of visible light illumination was 25 0 C. Intensity of visible light was 45 µEm -2 s -1 .
Light emission was measured at 30 0 C in 1-ml samples of cell suspension (chlorophyll
concentration: 5 µg/ml).
3. Addition of a fluidising agent such as benzyl alcohol is expected to
induce an increased resistance to UV-B damage and a faster recovery. In
contradiction with our expectations, BA acted as an agent which increased the
damage and decreased the recovery.
4. Although BA did not seem to inhibit the oxygen evolution of intact cells
cultivated for short periods of time, it acted as an efficient inhibitor of the
cyanobacterial cells cultivated for longer time periods.
5. Our data indicate that benzyl alcohol inhibits the protein synthesis
somewhere at the transcriptional level. Its membrane-fluidising effect manifests
itself to some extent at low concentrations when its toxic effect is less obvious.
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