Abstract
The major growth yield of a prototrophic strain of Bacillus stearothermophilus under aerobic conditions on salts medium containing ammonium nitrate as the nitrogen source and glucose or succinate as the carbon source was maximal at the lowest growth temperature employed and decreased steadily as the temperature was raised. The temperature optima for growth yield and for growth rate were thus different. The molar growth yield values of the thermophile, especially at the lower growth temperatures, were similar to those reported for aerobically grown mesophilic bacteria, both on glucose and on succinate. At the higher growth temperatures, a lower proportion of glucose carbon was incorporated into cells and a correspondingly greater proportion was left incompletely utilized in the medium, mostly as acetate. This suggests a greater inefficiency in the coordination of the nonoxidative and oxidative phases of glucose metabolism at the gigher temperatures. Another factor causing a decreased cell yield at higher temperatures was possibly an uncoupling of energy production from respiration. The rates of respiration by intact cells of the thermophile on glucose and on succinate followed the Arrhenius relationship from 55 C to 20 C, which is some 20 C below the minimal growth temperature of the organism. The Arrhenius constant was 17.1 kcal/mol for glucose oxidation and 13.5 kcal/mol for succinate oxidation. These results are comparable to those reported for some mesophiles, and they suggest that the inability of the thermophile to grow at temperatures below about 41 C is not due to an abnormally high temperature coefficient for the uptake and oxidation of the carbon source.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Bubela B., Holdsworth E. S. Amino acid uptake, protein and nucleic acid synthesis and turnover in Bacillus stearothermophilus. Biochim Biophys Acta. 1966 Aug 17;123(2):364–375. doi: 10.1016/0005-2787(66)90289-9. [DOI] [PubMed] [Google Scholar]
- Epstein I., Grossowicz N. Intracellular protein breakdown in a thermophile. J Bacteriol. 1969 Aug;99(2):418–421. doi: 10.1128/jb.99.2.418-421.1969. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Epstein I., Grossowicz N. Prototrophic thermophilic bacillus: isolation, properties, and kinetics of growth. J Bacteriol. 1969 Aug;99(2):414–417. doi: 10.1128/jb.99.2.414-417.1969. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Forrest W. W. Energies of activation and uncoupled growth in Streptococcus faecalis and Zymomonas mobilis. J Bacteriol. 1967 Nov;94(5):1459–1463. doi: 10.1128/jb.94.5.1459-1463.1967. [DOI] [PMC free article] [PubMed] [Google Scholar]
- INGRAHAM J. L. Growth of psychrophilic bacteria. J Bacteriol. 1958 Jul;76(1):75–80. doi: 10.1128/jb.76.1.75-80.1958. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ng H. Effect of decreasing growth temperature on cell yield of Escherichia coli. J Bacteriol. 1969 Apr;98(1):232–237. doi: 10.1128/jb.98.1.232-237.1969. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Payne W. J. Energy yields and growth of heterotrophs. Annu Rev Microbiol. 1970;24:17–52. doi: 10.1146/annurev.mi.24.100170.000313. [DOI] [PubMed] [Google Scholar]
- SENEZ J. C. Some considerations on the energetics of bacterial growth. Bacteriol Rev. 1962 Jun;26:95–107. [PMC free article] [PubMed] [Google Scholar]
- Sundaram T. K., Cazzulo J. J., Kornberg H. L. Anaplerotic CO2 fixation in mesophilic and thermophilic bacilli. Biochim Biophys Acta. 1969 Nov 18;192(2):355–357. doi: 10.1016/0304-4165(69)90377-8. [DOI] [PubMed] [Google Scholar]
- Sundaram T. K. Physiological role of pyruvate carboxylase in a thermophilic bacillus. J Bacteriol. 1973 Feb;113(2):549–557. doi: 10.1128/jb.113.2.549-557.1973. [DOI] [PMC free article] [PubMed] [Google Scholar]