Abstract
The steady-state growth rate of a marine isolate was related to the concentrations of several carbon and energy source substrates when these substrates limited growth simultaneously in continuous culture. Glucose limitation was characterized by a threshold of 0.21 mg/liter for growth, a half-maximal growth rate at 0.48 mg/liter, U-shaped curves in extractable pool concentration-versus-growth velocity plots, and slow maximal growth rates. Arginine addition reduced the glucose threshold to 0.008 mg/liter, more than doubled the maximal growth rate, and stabilized pool concentrations at low growth rates. Addition of a third substrate, glutamate, caused further reduction of the glucose concentration a steady state. Maximal reduction of the glucose concentration was effected by adding a mixture of 20 amino acids. Steady-state limiting nutrient concentration was dependent on the specific identity of the auxiliary nutrients and on the concentration ratio at which they were supplied. When glucose was supplemented with an equal quantity of an amino acid mixture, the external steady-state glucose remained below 10 mug/liter. When 1 mug of glucose was added to a 2.5-mg/liter amino acid mixture, at least 70% of it was consumed at steady state in spite of the threshold observed. Lack of crossover between metabolic pathways, suggested by the absence of glucose carbon in pool glutamate of arginine-glucose-grown cells, may have been partly responsible for the mixed carbon source stimulation of nutrient accumulation observed. The affinity observed is sufficient to account for normal growth at a total organic substrate concentration of only 0.11 mg/liter when supplied from a suitable mixture.
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Selected References
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- Button D. K., Dunker S. S., Morse M. L. Continuous culture of Rhodotorula rubra: kinetics of phosphate-arsenate uptake, inhibition, and phosphate-limited growth. J Bacteriol. 1973 Feb;113(2):599–611. doi: 10.1128/jb.113.2.599-611.1973. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Button D. K., Garver J. C. Continuous culture of Torulopsis utilis: a kinetic study of oxygen limited growth. J Gen Microbiol. 1966 Nov;45(2):195–204. doi: 10.1099/00221287-45-2-195. [DOI] [PubMed] [Google Scholar]
- Button D. K. Thiamine limited steady state growth of the yeast Cryptococcus albidus. J Gen Microbiol. 1969 Sep;58(1):15–21. doi: 10.1099/00221287-58-1-15. [DOI] [PubMed] [Google Scholar]
- HERBERT D., ELSWORTH R., TELLING R. C. The continuous culture of bacteria; a theoretical and experimental study. J Gen Microbiol. 1956 Jul;14(3):601–622. doi: 10.1099/00221287-14-3-601. [DOI] [PubMed] [Google Scholar]
- Jannasch H. W. Growth characteristics of heterotrophic bacteria in seawater. J Bacteriol. 1968 Feb;95(2):722–723. doi: 10.1128/jb.95.2.722-723.1968. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Shehata T. E., Marr A. G. Effect of nutrient concentration on the growth of Escherichia coli. J Bacteriol. 1971 Jul;107(1):210–216. doi: 10.1128/jb.107.1.210-216.1971. [DOI] [PMC free article] [PubMed] [Google Scholar]