480 



Atusi Takamiya, Hirosi Obata and Eijiro Yakushiji 



(i. e. , without addition of any detergent) are one of the remarkable character- 

 istics of this particular chlorophyll protein. The ultracentrifugal analysis of 

 the purified sample in a Spinco Ultracentrifuge (Model E, at 14° C) showed a 

 single-peaked sedimentation pattern, indicating the homogeneous dispersion of 

 the substance in the solution. The sedimentation constant was computed to be 

 S20' = 2. 7. 



Spectral Characteristic 



Fresh solution of the chlorophyll protein prepared in the dark is green in 

 color, which changes on standing in the light into yellowish-green. The solid 

 line in Fig. 1 shows the absorption spectrum of the native chlorophyll protein. 



300 



500 

 WAVELENGTH, m,. 



700 



400 



500 600 700 

 WAVELENGTH ,m^ 



Fig. 1 (left) Absorption spectra of Chenopodium chlorophyll protein (CP 668; 

 native form, CP 743 ; illuminated (partially photoconverted) form) 



Fig. 2 (right) Difference spectrum of photoconversion of Chenopodium 

 chlorophyll protein (CP 743 minus CP 668) 



The main peak at 668 m/x corresponds to the red-band of chlorophyllous com- 

 plex, the accompanying smaller accessory peak at 615 m/z, 575 m/j and 530 m/i 

 are also common in this group of substance. Another main absorption at 

 430 mju and the shoulder at 410 m/x represent the Soret bands of the chloro- 

 phyllous complex. The absorption at 277 m/n is probably due to the protein 

 content. The dotted line in the same figure shows the absorption spectrum of 

 the same sample of the chlorophyll protein, which had been illuminated for 30 

 seconds with white light (10, 000 lux). A new far-red peak appears at 743 my, 

 and there are also changes in the shorter region of the spectrum, new peaks 

 appearing at 364 rem and 400 my. The appearance of the peak at 565 nn/x is 

 also remarkable. The absorption at about 700 mji also rises considerably, 

 although it does not make a significant absorption peak. The difference 

 spectrum of the light-induced changes is shown in Fig. 2. 



