54 

 APT activities in cultured N. silvestris cells. 



When N. silvestris stationary phase cells were diluted 

 into fresh medium, a substantial elevation of soluble 

 protein occurred which increased until day 2, leveled off 

 between days 2 and 3, and began a steady decline between 

 days 3 and 7 as shown in Fig. 3-4B. This rise ceased before 

 mid- exponential growth was reached. That soluble protein 

 synthesis was terminated before reaching a maximum was 

 indicated by the finding that EE cells achieved a two- fold 

 higher content of soluble protein. EE cells exhibited a 

 consistently higher soluble protein content of about 360 mg 

 g dry wt.'-^. 



During the transition of cell populations in lag phase 

 to exponential -phase growth, new synthesis of macromolecular 

 constituents must have occurred. Figure 3-5A shows that the 

 rise in ADT activity expressed as units of activity per g 

 dry wt . , paralleled the rise in soluble protein between 

 subculture and day 2 (Fig. 3-4B) . The rise in ADT activity 

 levels continued until day 3, whereas overall soluble 

 protein content plateaued between days 2 and 3. Thus, 

 specific activity or activity expressed on a cell basis 

 peaked at day 3. Since the specific activity of E cells and 

 EE cells are similar and since the ratio of soluble protein 

 to dry weight is greater in EE cells than in E cells, the 

 activity of ADT expressed as units per g dry wt was greater 

 in EE cells than in E cells. The decline in specific 



