Two Fluorescent Probes Reflecting Different Light-Induced Processes in Rhodospirillum Rubrum Chromatophores

Abstract

In mitochondria and submitochondrial particles changes in the fluorescence of membrane-bound fluorochromes such as 8-anilino-1-naphthalene sulfonic acid (ANS) (WEBER & LAURENCE 1954) have been reported to be closely identified with energy conservation reactions (AZZI et al. 1969 PACKER et al. 1969, CHANCE et al. 1969, AZZI 1969, NORDENBRAND & ERNSTER 1970). Another fluorescent probe, atebrin, which is by itself an uncoupler (AVRON & SHAVIT 1965), has been tested in chloroplasts by KRAAYENHOF (1970). Illumination of a chloroplast suspension in its presence resulted in a quenching of the atebrin fluorescence and the quenching decreased when the system was uncoupled. The quenching could be induced by electron transport, ATP-hydrolysis or a pH gradient and was therefore suggested to be correlated with the energized state (KRAAYENHOF 1970).