A new rate law describing microbial respiration
A new rate law describing microbial respiration
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DOI：
10.1128/aem.69.4.2340-2348.2003
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发表时间：
2003-04-01
影响因子：
4.4
通讯作者：
Bethke, CM
中科院分区：
文献类型：
--
作者：
Jin, QS;Bethke, CM
微生物呼吸速率可以通过速率定律来描述，该速率定律将呼吸速率给出为速率常数、生物量浓度和三个项的乘积：一项描述给电子反应的动力学，一项描述电子接受反应的动力学，以及解释微生物环境中可用能量的热力学项。速率定律是在化学渗透理论和非线性热力学的基础上推导出来的，其独特之处在于它同时考虑了通过电子传输链的正向和反向通量。我们的分析证明了微生物的呼吸速率如何取决于热力学驱动力，即环境中可用的能量与以 ATP 形式保存的能量之间的净差。微生物学中常用的速率定律（例如莫诺方程）是所提出的一般定律的具体简化。新的速率定律意义重大，因为它提供了以严格的方式从实验室实验推断到广泛的自然条件的可能性，包括只有有限能量可用的微生物生长。速率定律还为阈值现象提供了新的解释，这可能反映了热力学平衡，其中电子转移释放的能量平衡了 ADP 磷酸化所守恒的能量。
The rate of microbial respiration can be described by a rate law that gives the respiration rate as the product of a rate constant, biomass concentration, and three terms: one describing the kinetics of the electron-donating reaction, one for the kinetics of the electron-accepting reaction, and a thermodynamic term accounting for the energy available in the microbe's environment. The rate law, derived on the basis of chemiosmotic theory and nonlinear thermodynamics, is unique in that it accounts for both forward and reverse fluxes through the electron transport chain. Our analysis demonstrates how a microbe's respiration rate depends on the thermodynamic driving force, i.e., the net difference between the energy available from the environment and energy conserved as ATP. The rate laws commonly applied in microbiology, such as the Monod equation, are specific simplifications of the general law presented. The new rate law is significant because it affords the possibility of extrapolating in a rigorous manner from laboratory experiment to a broad range of natural conditions, including microbial growth where only limited energy is available. The rate law also provides a new explanation of threshold phenomena, which may reflect a thermodynamic equilibrium where the energy released by electron transfer balances that conserved by ADP phosphorylation.