68 



THE FORMATION OF ENZYMES IN BACTERIA 



TABLE VI 



Comparison of the Activities of Esch. coli when Grown in Casein 

 Digest: (1) adjusted to pH 7, (2) adjusted to pH 5, and (3) containing 

 2 per cent glucose and attaining a final pK = 5-2. 

 Activities are expressed as Q units = fil. Og or CO2 or NH3 or 

 methylene blue (MB), etc., formed or reduced/hr./mgrm. dry weight 

 of organism. 



The presence of fermentable carbohydrate during growth 

 has four known effects: (1) the production of acid and con- 

 sequent alteration of the medium ^H; (2) the production of 

 gas with consequent anaerobiosis ; (3) a considerably increased 

 crop of organisms; and (4) the transient formation of poly- 

 saccharide within the growing and fermenting cell. Despite 

 various attempts, no one has yet succeeded in linking any of 

 these effects with the inhibition of formation of certain 

 enzymes. Monod has investigated the effect of growing the 



