Page 38 of Attachment H 
TABLE 5. 
PURIFICATION OF L-ASPARAGINASE FROM E. coli 
Step Protein a 
Enzyme 
Activity 
Specific 
Activity 
Yield 
g 
I.U. X 10 5 
I.U. /mg 
% 
Cell cake (10 kg) 
6.5 
100 
pH 4.5 extract 
34.0 
5.5 
1.6 
85 
50-90% (NH 4 ) 2 S0 4 
precipitate 
17.3 
4.9 
28.0 
75 
Ethanol precipitate 
6.0 
3.6 
60.0 
55 
Extract of lyophilized 
powder 
4.9 
3.5 
71.0 
54 
Crystalline enzyme 
0.54 
1.6 
294.0 
25 
Protein of crystalline enzyme was determined by weight after freeze- 
drying. Protein concentration of other fractions was determined as 
described under "Experimental Procedure." 
[ 474 ] 
