ISSN:
0006-3592
Keywords:
cephamycin
;
Nocardia lactamdurans
;
nutrient regulation
;
antibiotic fermentation
;
nitrogen metabolism
;
phosphate limitation
;
Chemistry
;
Biochemistry and Biotechnology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
A High cephamycin C producing strain of Nocardia lactam-durans was used to study cell growth and antibiotics production in defined media. Batch fermentations in shake flasks and stirred tanks showed that antibiotic production occurred during cell growth and the production rate rapidly decline as the growth slowed. Glutamate served as a primary substrate during this phase. Later, ammonia was utilized along with a remainder of the glucose. Rapid antibiotic production occurred in this phase. Increased glutamate promoted higher growth, a rise in ammonium ion concentration, and a marked reduction in antibiotic titers. An increase of the glucose concentration along with the glutamate concentration balanced to the medium; no ammonium ion rise occurred and a peak specific antibiotic titer comparable to the control medium was obtained. In a phosphate-limited medium, cell growth equivalent to the control medium and increased antibiotic titers were obtained. In these experiments, adjustment of Na+ and K+ ion concentration equal to that in the control medium was found to be important. Based on carbon and nitrogen balances, the activity of the key nitrogen metabolism enzymes, and the published literature, a two-stage model of regulation is suggested.
Additional Material:
12 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/bit.260380919
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