Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan.
Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Phys Rev Lett. 2020 Jan 31;124(4):048101. doi: 10.1103/PhysRevLett.124.048101.
Microbial cells generally leak various metabolites including those necessary to grow. Why cells secrete even essential chemicals so often is, however, still unclear. Based on analytical and numerical calculations, we show that if the intracellular metabolism includes multibody (e.g., catalytic) reactions, leakage of essential metabolites can promote the leaking cell's growth. This advantage is typical for most metabolic networks via "flux control" and "growth-dilution" mechanisms, as a general consequence of the balance between synthesis and growth-induced dilution with autocatalytic reactions. We further argue that this advantage may lead to a novel form of symbiosis among diverse cells.
微生物细胞通常会泄漏各种代谢物，包括生长所需的物质。然而，细胞为什么经常分泌即使是必需的化学物质仍然不清楚。基于分析和数值计算，我们表明，如果细胞内代谢包括多体（例如催化）反应，那么必需代谢物的泄漏可以促进泄漏细胞的生长。通过“通量控制”和“生长稀释”机制，这种优势对于大多数代谢网络来说是典型的，这是由于自催化反应的合成和生长诱导稀释之间的平衡的一般结果。我们进一步认为，这种优势可能导致不同细胞之间形成一种新的共生形式。
