SUMMARY: 8602 was grown in continuous culture in minimal salts medium with 10 m-succinate as carbon source. Changes in bacterial concentration and amidase activity were measured when the carbon source in the ingoing medium was changed to 10 m-succinate plus 10 m-acetamide. At low dilution rates ( = 0.2 hr) amidase synthesis occurred rapidly with little or no lag. At higher dilution rates the lag increased until at the highest dilution rate tested ( = 0.76 hr) almost no amidase had been synthesized 4 hr after the change of medium. It was concluded that at the highest dilution rates amidase synthesis was subject to catabolite repression by high intracellular concentrations of succinate and its metabolites. Severe repression of amidase synthesis was accompanied by incomplete utilization of acetamide for growth.

Periodic oscillations were observed in amidase activity and in bacterial concentration both during the transition period after the change of medium and when the culture had reached the new steady state. These oscillations occurred at all dilution rates and oscillations in amidase activity were also found when the non-substrate inducer -acetylacetamide was supplied with 20 m-succinate.


Article metrics loading...

Loading full text...

Full text loading...


Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error