Resolution of components of the absorption spectrum of chlorophyll‐protein 668 and its phototransformation product in Atriplex hortensis

The absorption spectra of a highly purified water‐soluble chlorophyll‐protein, CP 668, obtained from upper leaves of Atriplex hortensis L., and its phototransformation product have been measured and analyzed as sums of component curves. The difference spectrum before and after transformation has the same major peaks as those previously reported for a preparation from Chenopodium. The curve resolution indicates that, unlike some previous studies with preparations from other species of CP 668 from Atriplex, the main red band is a single, though somewhat unsymmetrical, component very much like the chlorophyll α 670 (Ca 670) common to all green plants. The “740” band of the phototransformed material, however, appears to have at least two components. The amounts of photoconversion of this pigment‐protein was more extensive than any complex previously studied. The converted material had a far‐red to red absorbance ratio of 2.6.