Blue-Light Photoreception in the Inhibition and Synchronization of Growth and Transport in the Yeast Saccharomyces

Abstract

Visible light has been shown to inhibit growth [8, 10, 18], respiration [10, 12, 14], protein synthesis [9], and membrane transport [18] in bakers’ yeast and to have a deleterious effect on membrane integrity [18]. Several observations suggest that cytochromes participate in these inhibitory light effects. Blue light has been identified as the maximally inhibitory wavelength in investigations on growth, protein synthesis, and respiration [8, 9] and on respiratory adaptation [11] of anaerobically grown yeast cells. Ninnemann et al. [15] have shown that the inhibition of respiration by high intensity blue light was due to the destruction of cytochromes a/a₃ and partial destruction of cytochrome b. Finally, we have recently demonstrated [18] that respiratory-deficient petite (rho ^-) yeasts lacking cytochromes b and a/a₃ are resistant to light intensities that photokill wild-type (rho ⁺) parent cells.

Preliminary portions of these results were presented at the VII International Congress on Photo-biology, Rome, Italy (29 August-3 September 1976); at the 77th Annual Meeting of the American Society for Microbiology, New Orleans, Louisiana (8–13 May 1977); at the 5th Annual Meeting of the American Society for Photobiology, San Juan, Puerto Rico (11–15 May 1977); and at the XIII and XIV International Conferences of the International Society for Chronobiology, Pavia, Italy (4–7 September 1977) and Hannover, Federal Republic of Germany (8–12 July 1979)