The Novo Nordisk Center for Biosustainability, Technical University of Denmark, Kemitorvet 220, DK-2800, Kgs. Lyngby, Denmark.
Sci Rep. 2023 May 2;13(1):7131. doi: 10.1038/s41598-023-33918-1.
Parageobacillus thermoglucosidasius is a thermophilic bacterium characterized by rapid growth, low nutrient requirements, and amenability to genetic manipulation. These characteristics along with its ability to ferment a broad range of carbohydrates make P. thermoglucosidasius a potential workhorse in whole-cell biocatalysis. The phosphoenolpyruvate:carbohydrate phosphotransferase system (PTS) catalyzes the transport and phosphorylation of carbohydrates and sugar derivatives in bacteria, making it important for their physiological characterization. In this study, the role of PTS elements on the catabolism of PTS and non-PTS substrates was investigated for P. thermoglucosidasius DSM 2542. Knockout of the common enzyme I, part of all PTSs, showed that arbutin, cellobiose, fructose, glucose, glycerol, mannitol, mannose, N-acetylglucosamine, N-acetylmuramic acid, sorbitol, salicin, sucrose, and trehalose were PTS-dependent on translocation and coupled to phosphorylation. The role of each putative PTS was investigated and six PTS-deletion variants could not grow on arbutin, mannitol, N-acetylglucosamine, sorbitol, and trehalose as the main carbon source, or showed diminished growth on N-acetylmuramic acid. We concluded that PTS is a pivotal factor in the sugar metabolism of P. thermoglucosidasius and established six PTS variants important for the translocation of specific carbohydrates. This study lays the groundwork for engineering efforts with P. thermoglucosidasius towards efficient utilization of diverse carbon substrates for whole-cell biocatalysis.
热葡糖苷菌（Parageobacillus thermoglucosidasius）是一种嗜热细菌，具有生长迅速、营养需求低、易于遗传操作等特点。这些特性以及其能够发酵广泛的碳水化合物的能力，使热葡糖苷菌成为全细胞生物催化的潜在“主力军”。磷酸烯醇丙酮酸：碳水化合物磷酸转移酶系统（PTS）催化细菌中碳水化合物和糖衍生物的运输和磷酸化，对于其生理特性的研究具有重要意义。在本研究中，研究了热葡糖苷菌 DSM 2542 中 PTS 元件对 PTS 和非 PTS 底物分解代谢的作用。敲除所有 PTS 共有的酶 I 表明，熊果苷、纤维二糖、果糖、葡萄糖、甘油、甘露醇、甘露糖、N-乙酰葡萄糖胺、N-乙酰胞壁酸、山梨醇、水杨苷、蔗糖和海藻糖的转运和磷酸化依赖 PTS。研究了每个假定 PTS 的作用，六个 PTS 缺失变体不能以熊果苷、甘露醇、N-乙酰葡萄糖胺、山梨醇和海藻糖作为主要碳源生长，或以 N-乙酰胞壁酸作为主要碳源生长能力减弱。我们得出结论，PTS 是热葡糖苷菌糖代谢的关键因素，并建立了六个 PTS 变体，这些变体对于特定碳水化合物的转运很重要。这项研究为利用热葡糖苷菌进行全细胞生物催化，高效利用多种碳源的工程努力奠定了基础。
