PROPERTIES OF CHLOROPHYLL PROTEIN ISOLATED FROM 

 LEAVES OF CHENOPODIUM ALBUM 



Atusi Takamiya, Hirosi Obata and Eijiro Yakushiji 



INTRODUCTION 



Various attempts have been made to disintegrate chloroplasts into its 

 constituent units and obtain chlorophyll in the nearest-to-nature state as it 

 occurs in the photosynthetic apparatus. The isolation of chloroplastin^ ' K 

 protochlorophyll holochrome(3) and quantasome(4) may be regarded as the 

 most prominent achievements along this line of approach. The purpose of the 

 present report is to make another addition to this group of chlorophyll proteins. 

 The new chlorophyll protein was discovered by one of us (Yakushiji) during his 

 investigation on the isolation of cytochromes from various plant materiaiv^). 

 On extracting the leaves of the weed, Chenopodium album , with the ordinary 

 phosphate buffer and viewing the brownish crude extract with the hand spectro- 

 scope, an absorption band was discovered at 565 my. Attempts were then 

 made to isolate the substance and it was finally obtained in purified form^5). 



ISOLATION AND PURIFICATION 



Since this particular chlorophyll protein is highly light-sensitive, care 

 must be taken to carry out the following purification procedures in dim (green) 

 light, to obtain the substance in its native state. The substance is extracted 

 from the fresh (or deep-frozen) leaves of Chenopodium album by homogenation 

 in 0.01 M disodium phosphate solution and concentrated by collecting the frac- 

 tion precipitating between 0. 3 and 0. 6 saturation with ammonium sulfate. The 

 precipitate is dissolved in 0. 01 M phosphate buffer, pH 7. 8 and, after dialysis 

 against the same buffer solution, subjected to chromatography on a column of 

 Amberlite CO 50. The substance can be adsorbed and washed on the column 

 at concentrations of 0.01 - 0. 02 M, and eluted out -at 0. 5 M of the phosphate 

 buffer, pH 7. 8. Subsequent ammonium sulfate fractionation was repeated 

 several times and the final product of the pure chlorophyll protein was stored 

 in 0. 1 M phosphate buffer, pH 7. 8, which may be stored without any deteriora- 

 tion, if kept in the dark and in a frozen state. 



PROPERTIES OF CHLOROPHYLL PROTEIN 



The substance is water-soluble and gives a clear solution when dissolved 

 in water or buffer solution. The solubility and stability in plain aqueous media 



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