Barato Andre C, Seifert Udo
II. Institut für Theoretische Physik, Universität Stuttgart, 70550 Stuttgart, Germany.
J Phys Chem B. 2015 Jun 4;119(22):6555-61. doi: 10.1021/acs.jpcb.5b01918. Epub 2015 May 19.
The Fano factor, an observable quantifying fluctuations of product generation by a single enzyme, can reveal information about the underlying reaction scheme. A lower bound on this Fano factor that depends on the thermodynamic affinity driving the transformation from substrate to product constrains the number of intermediate states of an enzymatic cycle. So far, this bound has been proven only for a unicyclic network of states. We show that the bound can be extended to arbitrary multicyclic networks, with the Fano factor constraining the largest value of the effective length, which is the ratio between the number of states and the number of products, among all cycles.
法诺因子是一种可观测的量，用于量化单一酶产生产物的波动情况，它能够揭示有关潜在反应机制的信息。该法诺因子的下限取决于驱动底物向产物转化的热力学亲和力，它限制了酶促循环中间态的数量。到目前为止，这个下限仅在单环状态网络中得到证明。我们表明，该下限可以扩展到任意多环网络，其中法诺因子限制了有效长度的最大值，有效长度是所有循环中状态数与产物数之比。
