GENETIC CONTROL OF CELL INTEGRATION 



335 



TABLE 11.2 



Mutations Affecting Formation of the Enzyme Penicillinase in 



Strains of Bacillus cereus" 



(After Pollock, 1959, in: The Enzymes (2nd ed.), Boyer, P. D., Lardy, H., and 

 Myrback, K. (eds. ), Academic Press, Vol. 1:619) 



Noninducible Strains 

 Strain 5 

 ^5 



Inducible Strains 



Strain 569 ("Inducible") Induction -^-569 



with 

 penicillin / 



/ 

 / 



/ 



\ /(^ 25,000^ 



\ / ^ ^ 



\ f 



Deadaptation by 



growth without 



penicillin 



569M Induction ^ 569M 



with ^ 



penicillin V: 



35,000 



I 3.0 I Q 75,000^ 



I I = upper limit of penicillin resistance in units per ml. 



(^ = molecules of penicillinase per cell. 

 M = mutation. 



° In B cereus mutations have been observed which affect penicillin resistance 

 level, rate of formation of penicillinase, and inducibility of enzyme synthesis by 

 penicillin. These properties vary independently, indicating that each of them 

 is under control of a mutationally different genetic element. 



