Wlaźlak Małgorzata, Cielecka Izabela, Daroch Maurycy
Institute of Molecular and Industrial Biotechnology, Lodz University of Technology, B. Stefanowskiego 2/22, 90-537, Lodz, Poland.
School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen, China.
Appl Microbiol Biotechnol. 2025 Sep 2;109(1):194. doi: 10.1007/s00253-025-13583-2.
Bacterial nanocellulose (BNC) is a valuable biopolymer with immense potential in various sectors of biotechnology. However, large-scale production is hindered by low yields and high costs. Glycerol is an inexpensive and widely available carbon source for BNC biosynthesis, as it is a by-product of the biofuel industry. Compared to glucose, this polyol enhances BNC yields of Novacetimonas hansenii SI1 and related strains. This study investigates transcriptomic changes in N. hansenii SI1 after switching from glucose to glycerol using RNA-seq. The results reveal metabolic reprogramming, including upregulation of genes involved in glycerol uptake and catabolism, gluconeogenesis, the pentose phosphate pathway, and the Entner-Doudoroff pathway. Glycerol metabolism induces oxidative stress, evidenced by elevated expression of antioxidant enzymes, repair proteins, and metal ion homeostasis systems. Additionally, pathways such as riboflavin biosynthesis, methionine salvage, and sulphur assimilation are upregulated to mitigate oxidative damage. Increased oxidative conditions likely stimulate c-di-GMP synthesis, activating cellulose synthase and promoting BNC production. Furthermore, the acetan-like polymer biosynthetic pathway is significantly induced, further enhancing BNC yield. These findings expand our understanding of glycerol utilisation in BNC production, supporting cost-efficient and eco-friendly processes for maximising biopolymer exploitation. KEY POINTS: • Growth on glycerol remodels central carbohydrate metabolism • Glycerol metabolism induces oxidative stress • Acetan-like biosynthesis and posttranslational effects stimulate BNC production.
细菌纳米纤维素（BNC）是一种有价值的生物聚合物，在生物技术的各个领域具有巨大潜力。然而，低产量和高成本阻碍了其大规模生产。甘油是一种廉价且广泛可得的用于BNC生物合成的碳源，因为它是生物燃料行业的副产品。与葡萄糖相比，这种多元醇可提高汉氏新醋杆菌SI1及相关菌株的BNC产量。本研究使用RNA测序研究了汉氏新醋杆菌SI1从葡萄糖转换为甘油后转录组的变化。结果揭示了代谢重编程，包括参与甘油摄取和分解代谢、糖异生、磷酸戊糖途径和恩特纳-杜德洛夫途径的基因上调。甘油代谢诱导氧化应激，抗氧化酶、修复蛋白和金属离子稳态系统的表达升高证明了这一点。此外，核黄素生物合成、甲硫氨酸补救和硫同化等途径上调以减轻氧化损伤。氧化条件增加可能刺激环二鸟苷酸（c-di-GMP）合成，激活纤维素合酶并促进BNC生产。此外，类乙酰聚合物生物合成途径被显著诱导，进一步提高了BNC产量。这些发现扩展了我们对BNC生产中甘油利用的理解，支持了成本效益高且环保的工艺以最大限度地开发生物聚合物。要点：• 在甘油上生长重塑了中心碳水化合物代谢 • 甘油代谢诱导氧化应激 • 类乙酰生物合成和翻译后效应刺激BNC生产
