Kinetic studies of pigment synthesis by non-sulfur purple bacteria
Cohen-Bazire, G.; Sistrom, W.R.; Stanier, R.Y.
Journal of Cellular and Comparative Physiology 49(1): 25-68
Methods have been developed for the quantitative study of pigment synthesis by photosynthetic bacteria under controlled growth conditions, and applied to two species, Rhodopseudo-monas spheroides and Rhodospirillum rubrum. Under anaerobic conditions in the light, the rate of pigment synthesis is inversely related to light intensity. When light intensity is changed suddenly, the pigment content of the cells is adjusted by either a suppression or a stimulation of the rate of pigment synthesis. Increased light intensity causes suppression; decreased light intensity, stimulation. Under aerobic conditions in both light and dark, pigment synthesis is almost completely suppressed. On the basis of these observations, it is postulated that the rates of chlorophyll and carotenoid synthesis are both governed by the state of oxidation of a carrier in the electron transport system.