AMINO ACIDS AND DERIVATIVES IN DROSOPHILA I41I 
of these problems the method is adequate for the present purposes and it is especially 
informative. 
COLUMN CHROMATOGRAPHY OF FRACTIONS SEPARATED BY EXTRACTION 
The extraction method described earlier (Figs. 3 and 4) has consistently yielded 
results that appear to represent a sharp separation of different classes of substances. 
LETHAL - TRANSLUCIDA 
MICROMOLES 

FRACTION 
Fig. 5. Patterns of ninhydrin-reacting compounds in Fractions t and 3 from wild-type larvae and 
two mutants. Data on materials from Fraction rt are shown on the left and from Fraction 3 at the 
right. Shaded areas show ninhydrin equivalents before hydrolysis and black areas the total after 
acid hydrolysis. Fraction-3 components gave the ninhydrin reaction before hydrolysis amounting 
to 2-10 % of the total after hydrolysis and in this elution system only negligible amounts of any 
substance were eluted before tube No. 85. Columns: 1.6 X 15 cm, Dowex-50-4X equilibrated with 
starting buffer. Elution: linear gradient with an inverted funnel system and the following succession 
of solvents. 
Change in 
Solvent pH (CED solvent at 
aed fraction 
1. Trimethylamine formate 2.5 0.025 7 
2. Trimethylamine formate 3.15 0.05 17 
3. Trimethylamine formate 3-5 0.075 39 
4. Trimethylamine formate 3-95 0.10 60 
5. Irimethylamine acetate 4.55 0.40 78 
6. Trimethylamine formate 9.6 1.0 95 
g-ml fractions were lyophilized and redissolved for analysis without heating. As shown in the graph 
for wild type, the common amino acids are all eluted between tubes No. 50 and r1o. 
References p. 146 
