481 



Atusi Takamiya, Hirosi Obata and Eijiro Yakushiji 



Pigment Components of the Chlorophyll Protein 



On addition of higher concentrations of organic solvents, such as alcohol 

 and acetone, there occur abrupt changes in absorption of the chlorophyll pro- 

 tein. The red band of the non-illuminated form shifts from 668 m/x to 663 m/x, 

 and the far-red peak at 743 nyj. characteristic of the illuminated form disappears 

 by the treatment to give rise to a new but less remarkable peak at 718 m/i. 

 With still higher concentrations of the organic solvent, the green color of the 

 substance is extracted in solution. The absorption spectra of such alcohol 

 extracts are shown in Fig. 3. The pigment in the extract was analyzed by paper 

 chromatography according to Jeffrey, using petrol ether containing 2% iso- 

 propanol as developing solution'"'. The presence of chlorophylls a and b in the 

 extract of the non-illuminated sample was confirmed by spectrophotometric 

 examination of the pigments eluted from the corresponding spots. In the chro- 

 matogram of the illuminated form, the spot corresponding to chlorophyll a 

 considerably diminishes, while the spot of the b component remained essentially 

 the same. These features correspond to the difference between the absorption 

 spectra of the extracts of illuminated and non-illuminated samples of the chloro- 

 phyll protein. There were two new green spots also showing red fluorescence 

 in the chromatogram of the illuminated form, which remain still unidentified. 

 No carotenoid content was discovered in the purified substance. The protein 

 nature of the substance was also confirmed by the ninhydrin and Biuret tests. 



30 40 



Time ( min) 



50 60 



Fig. 3 (left) Absorption spectra of alcoholic extracts of Chenopodium 

 chlorophyll protein (CP 66^ and CP 743 ) 



Fig. 4 (right) Time course of photoconversion of Chenopodium chlorophyll 

 protein; CP 668 - CP 743 



From the above-described facts and especially from the content of 

 chlorophylls a and b in its native (i.e. non-illuminated) form, the substance 

 was inferred to be a chlorophyll-protein compound and the designation as 

 Chenopodium chlorophyll protein CP 668 is proposed according to the position 

 of its red-peak. The illuminated form will be indicated as CP 743. 



