Detection of a Phytochrome‐like Protein in Macroalgae

Abstract

Abstract A phytochrome‐like protein was detected in extracts from the red algae Corallina elongata and Gelidium sp., from the brown algae Cystoseira abiesmarina and Cystoseira tamariscifolia , and from the green algae Ulva rigida, Enteromorpha compressa and Chara hispida . Relative amounts of the photoreversible protein were determined by measurement of Δ (Δ A ) values of the crude extract. SDS gel electrophoresis and immunoblotting with monoclonal antibodies directed to phytochrome from etiolated maize and oat seedlings revealed only one phytochrome‐related band with apparent molecular weight of 130 kDa. The absorption difference spectrum after partial purification showed a “normal” absorption band (λ max = 670 nm) for the Pr form but only a very weak band (λ max = 705 nm) for the “Pfr form”.