CHLOROPHYLLASE 231 



methyl analogue of ethylchlorophylHde or crystalline chloro- 

 phyll ; it is best obtained by treating fresh leaves with 50-60 

 per cent methyl alcohol ; if prepared from Heracleum it is 

 sparingly soluble in ether and crystallizes from that solvent 

 in steel-blue glistening prisms ; that prepared from stinging 

 nettles is slightly less soluble in ether and crystallizes in 

 triangular and hexagonal plates. 



By acting in moist ethereal solution in the absence of 

 alcohol, ordinary hydrolysis was effected with the formation 

 of the monomethyl ester of the chlorophyllin, namely chloro- 

 phyll ide — • 



/COOH 

 C3iH23N4Mg— COOH 



\cOOCH3 



this is an extremely unstable substancewhich forms green plates. 



The enzyme is sensitive to high temperatures, and when 

 boiled with alcohol it is gradually destroyed ; its activity is 

 greater at 25° than at 30". 



Chlorophyll appears to be always accompanied by the 

 enzyme, the amount increasing with the amount of chlorophyll, 

 and hence young leaves appear to contain less enzyme than 

 the older ones. In Pyrus Auaiparla, Mellitis Melissophyllum, 

 Stachys silvatica, Lamiuvi niaculatuin, and Heracleum the 

 amount of enzyme is comparatively large. Urtica, Avena, 

 ordinary grasses, Sambucus^ Platanus, Aspzdiuin, Equisetuin, 

 and Taxus, may be conveniently employed for demonstrating 

 the effect of the enzyme by leaving the tissues in contact with 

 an alcoholic extract of amorphous chlorophyll ; practically all 

 the phytol is thereby removed. 



The enzyme is also able to effect the synthesis of phytyl 

 chlorophyllide (amorphous chlorophyll) from chlorophyllide 

 and phytol. 



The constitution of this alcohol phytol has been studied by 

 Willstatter, Meyer, and Hlini,* who find it to be unsaturated 

 and to have the formula CogRggOH. 



THE CONSTITUTION OF CHLOROPHYLL. 



The chemistry of chlorophyll has received marked attention, 

 but, until quite recently, the results achieved have led to much 



* Willstatter, Meyer and Hiiiii : " Annalen," 1910, 378, 73. 



