Properties of a pigment system consisting of carotenoids and reaction centre pigments in chromatophores of Rhodospirillum rubrum.

A pigment system containing carotenoids and oxidised reaction centre pigments is present in chromatophores of Rhodospirillum rubrum and this pigment system may cause fluorescence quenching when a still unidentified chromatophore component is in its oxidised state. Besides by its action spectrum, this pigment system is characterised by the time course and level of light saturation of the effect. The quenching of bacteriochlorophyll fluorescence is abolished when the permeability of the chromatophore membranes is affected.

Comparison of the long-wave chlorophyll fluorescence in various green and blue-green algae and diatoms.

Two types of long-wave fluorescence bands with similar band shape occur at room temperature in various algae: FII700 and FI715. FII700 occurs in a limited number of algae, follows PS II transients, increases with culture age and is moderately increased by cooling to 83 K. FI715 occurs in most algae, especially Anabaena, but much less in most diatoms and Tribonema.