Abstract
Respiratory and luminescent systems in Photobacterium phosphoreum were reinvestigated by using intact cells and supernatant from cold osmotic shock. Time course pattern and activity of luminescence were quite different between the in vivo and in vitro systems. In the in vitro system, chemicals generally used as respiratory inhibitors inhibited luminescence rather than NADH oxidation.
Luminescent activities were completely lost in both systems by UV irradiation at 360mμ. Seventy per cent of respiratory activity in the in vitro system survived after UV irradiation, while almost none of that in the in vivo system remained. None of flavins and quinones added to both systems resulted in an increase in luminescence. Extraction of the in vitro system with solvents gave 2-3 fold increase in luminescent activity. Decanal addition gave a similar effect. Possibility of participation of quinones and aldehydes in luminescence is discussed.
