138 HILLEL S. LEVINSON 



Table I 

 The enzymatic activities of intact spores, vegetative cells 

 and treated spores 



System 



Table II compares the activities in the extracts and debris from disrupted 

 homogenates. It is apparent that GS activity is associated with both frac- 

 tions while, as expected because of non-dialyzable, assumed bound substrate, 

 XTF activity is associated only with the debris fraction. The total recovery 

 of GTF activity is less than expected and suggests that other factors may be 

 necessary for GTF activity. The loss of kinase activitv upon separation of 

 the homogenate indicates that a necessary cof actor (CoA?) may be in the 

 extract while the enzyme is in the particulate fraction. 



Table III compares the effect of heat shock prior to disruption on enzyme 

 activity to that of unheated disrupted spores. Perhaps the most striking 

 chans^e occurs in the acetokinase-like activity which becomes apparent after 

 only 15 minutes of heat shock and is markedly increased bv one hour heat 

 shock. GTF and XTF activity decrease markedly while GS activity is rela- 

 tively unaffected. It is possible that XTF activitv decreases not because of 

 enzvme inactivation but because of substrate inactivation. Experiments in 

 which spores were heat shocked for one hour and subsequently disrupted 

 for one half-hour and one hour showed similar effects on the activities, thus 

 indicatina; that the effect on the enzvmes was a thermal effect in the intact 

 spore and was not simolv a result of disinteerration. 



These results suggest that the differential effects attained through heat 

 shock on enzymes in the intact spore may approximate the conditions which 



Table II 

 The enzymatic activities of spore extracts and particulate fractions 



System 



* Activity in presence of AMP 



