Goyal Sidhartha, Wingreen Ned S
Department of Physics, Princeton University, Princeton, NJ 08544, USA.
Phys Rev Lett. 2007 Mar 30;98(13):138105. doi: 10.1103/PhysRevLett.98.138105.
Product-feedback inhibition is a ubiquitous regulatory scheme for maintaining homeostasis in living cells. Individual metabolic pathways with product-feedback inhibition are stable as long as one pathway step is rate limiting. However, pathways are often coupled both by the use of a common substrate and by stoichiometric utilization of their products for cell growth. We show that such a coupled network with product-feedback inhibition may exhibit limit-cycle oscillations which arise via a Hopf bifurcation. Our results highlight novel evolutionary constraints on the architecture of metabolism.
产物反馈抑制是一种在活细胞中维持稳态的普遍调控机制。只要一个途径步骤是限速的,具有产物反馈抑制的单个代谢途径就是稳定的。然而,途径通常通过使用共同底物以及其产物的化学计量利用来耦合以实现细胞生长。我们表明,这样一个具有产物反馈抑制的耦合网络可能会表现出通过霍普夫分岔产生的极限环振荡。我们的结果突出了对代谢结构的新的进化限制。