REGULATION OF LYSINE EPSILON-AMINOTRANSFERASE BY CARBON SOURCE AND LACK OF CONTROL BY PHOSPHATE IN STREPTOMYCES-CLAVULIGERUS

Cephalosporin production by Streptomyces clavuligerus is known to be n egatively regulated by carbon sources, e.g., glycerol and starch, and by phosphate at high concentrations. Formation of lysine E-aminotransf erase (LAT) activity, the first enzyme of the biosynthetic pathway, wa s affected by a high concentration of carbon source. Whereas 3% starch more than doubled LAT activity production as compared to 1% starch, 3 % glycerol repressed LAT activity formation by 20%-30%. LAT activity p roduction was not affected by 100 mM K2HPO4. Our results thus show tha t the negative effects of 2% glycerol and 3% starch and 100 mM phospha te on cephalosporin production are not due to an effect on production of LAT activity. However, repression of LAT activity by 3% glycerol wo uld be expected to play a negative role in antibiotic production.