Comprehensive analysis of central carbon metabolism illuminates connections between nutrient availability, growth rate, and cell morphology in Escherichia coli

Bacterial morphology is a complex trait that is highly sensitive to changes in the environment. For heterotrophic organisms, such as Escherichia coli, increases in nutrient levels are frequently accompanied by several-fold increases in both size and growth rate. Despite the dramatic nature of these changes, how alterations in nutrient availability translate into changes in growth and morphology remains a largely open question. To understand the signaling networks coupling nutrient availability with size and shape, we examined the impact of deletions in the entirety of non-essential central carbon metabolic genes on E. coli growth rate and cell size. Our data reveal the presence of multiple metabolic nodes that play important yet distinctive roles in dictating biosynthetic capacity and shaping cell morphology. Specifically, perturbations of acetyl-CoA metabolism impact cell size and division through changes in fatty acid synthesis. Additionally, we identify a genetic pathway linking glucose levels to cell width through the signaling molecule cyclic-AMP. Together our findings highlight a surprising diversity of factors and mechanisms contributing to growth potential and cell morphology, providing a foundation for further studies.细菌形态是一类复杂的性状，对环境变化具有高度敏感性。对于异养生物而言，例如大肠杆菌（Escherichia coli），营养水平提升往往伴随细胞尺寸与生长速率数倍的增长。尽管这些变化十分显著，但营养可获得性的改变如何转化为生长与形态的变化，在很大程度上仍是一个未被充分解答的问题。为解析将营养可获得性与细胞尺寸、形态关联起来的信号网络，我们探究了全部非必需中心碳代谢基因的敲除对大肠杆菌生长速率与细胞尺寸的影响。我们的数据揭示了多个代谢节点的存在，这些节点在调控生物合成能力与塑造细胞形态方面发挥着重要且独特的作用。具体而言，乙酰辅酶A（acetyl-CoA）代谢的扰动可通过改变脂肪酸合成途径，影响细胞尺寸与分裂过程。此外，我们还发现了一条通过信号分子环腺苷酸（cyclic-AMP）将葡萄糖水平与细胞宽度关联起来的遗传通路。综上，我们的研究结果揭示了调控生长潜能与细胞形态的众多因子与机制，展现出令人意外的多样性，为后续研究奠定了基础。