Academic Journal
Oxygen consumption in the marine bacterium Pseudomonas nautica predicted from ETS activity and bisubstrate enzyme kinetics
| العنوان: | Oxygen consumption in the marine bacterium Pseudomonas nautica predicted from ETS activity and bisubstrate enzyme kinetics |
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| المؤلفون: | Packard, T.T., Berdalet, E., Blasco, D., Roy, S.O., St-Amand, L., Lagacé, B., Lee, K., Gagnó, J.-P. |
| بيانات النشر: | Oxford University Press |
| سنة النشر: | 1996 |
| المجموعة: | HighWire Press (Stanford University) |
| مصطلحات موضوعية: | ORIGINAL ARTICLES |
| الوصف: | The respiratory O 2 consumption in aerobic bacterial cultures has been modeled from the time profiles of the in vitro activity of the respiratory electron transfer system (ETS), the bacterial protein and the concentration of the carbon source in the cultures. The model was based on the concept of bisubstrate kinetic control of the ETS throughout the exponential, steady-state and senescent phases of the cultures. In the exponential phase, the measured rates of O 2 consumption and the in vitro ETS activity were closely coupled, but in the senescent phase, they were uncoupled. The in vitro ETS activity remained high even after the culture's carbon source was exhausted, while the O 2 consumption fell to low levels. Based on the hypothesis that this uncoupling was caused by limitation of the intracellular ETS substrates (NADH and NADPH), a semi-empirical model incorporating a bisubstrate enzyme kinetics algorithm was formulated and fitted to the observations of the experiments. The model predicted the rate of O 2 consumption throughout the different phases of the cultures with an r 2 > 0.92 (n = 9, P < 0.001) using physiologically realistic Michaelis and dissociation constants. These results suggest that plankton respiration in the field could be assessed more accurately than before by measuring the intracellular ETS substrates (NADH and NADPH), in addition to ETS activity, in plankton. |
| نوع الوثيقة: | text |
| وصف الملف: | text/html |
| اللغة: | English |
| Relation: | http://plankt.oxfordjournals.org/cgi/content/short/18/10/1819; http://dx.doi.org/10.1093/plankt/18.10.1819 |
| DOI: | 10.1093/plankt/18.10.1819 |
| الاتاحة: | http://plankt.oxfordjournals.org/cgi/content/short/18/10/1819 https://doi.org/10.1093/plankt/18.10.1819 |
| Rights: | Copyright (C) 1996, Oxford University Press |
| رقم الانضمام: | edsbas.99E48F7C |
| قاعدة البيانات: | BASE |
| DOI: | 10.1093/plankt/18.10.1819 |
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