Question 251341

:

(1) a strain with a mutant gene encoding Pol I such that it no longer has polymerase activity (but retains both types of nuclease activities);                               

(2) a strain without RNaseH proteins;                                

(3) a strain with a mutant gene encoding Pol I such that it no longer has 5´ to 3´ exonuclease activities (but retains 3´ to 5´ nuclease and polymerase activities);

(4) a strain with the mutant Pol I described in (5)and a strain lacking all RNaseH proteins.