Division of Biotechnology, School of Bioresources and Technology, King Mongkut's University of Technology Thonburi (Bang Khun Thian), Bangkok, 10150, Thailand.
Systems Biology and Bioinformatics Research Group, Pilot Plant Development and Training Institute, King Mongkut's University of Technology Thonburi (Bang Khun Thian), Bangkok, 10150, Thailand.
Sci Rep. 2019 Feb 27;9(1):2964. doi: 10.1038/s41598-019-39920-w.
Analysis of metabolic flux was used for system level assessment of carbon partitioning in Kasetsart 50 (KU50) and Hanatee (HN) cassava cultivars to understand the metabolic routes for their distinct phenotypes. First, the constraint-based metabolic model of cassava storage roots, rMeCBM, was developed based on the carbon assimilation pathway of cassava. Following the subcellular compartmentalization and curation to ensure full network connectivity and reflect the complexity of eukaryotic cells, cultivar specific data on sucrose uptake and biomass synthesis were input, and rMeCBM model was used to simulate storage root growth in KU50 and HN. Results showed that rMeCBM-KU50 and rMeCBM-HN models well imitated the storage root growth. The flux-sum analysis revealed that both cultivars utilized different metabolic precursors to produce energy in plastid. More carbon flux was invested in the syntheses of carbohydrates and amino acids in KU50 than in HN. Also, KU50 utilized less flux for respiration and less energy to synthesize one gram of dry storage root. These results may disclose metabolic potential of KU50 underlying its higher storage root and starch yield over HN. Moreover, sensitivity analysis indicated the robustness of rMeCBM model. The knowledge gained might be useful for identifying engineering targets for cassava yield improvement.
利用代谢通量分析对 Kasetsart 50（KU50）和 Hanatee（HN）木薯品种的碳分配进行系统水平评估，以了解它们不同表型的代谢途径。首先，基于木薯的碳同化途径，建立了木薯块根的约束代谢模型 rMeCBM。随后进行了亚细胞区室化和编纂，以确保网络的完全连通性并反映真核细胞的复杂性，并输入了蔗糖摄取和生物量合成的特定于品种的数据，然后使用 rMeCBM 模型模拟 KU50 和 HN 中的块根生长。结果表明，rMeCBM-KU50 和 rMeCBM-HN 模型很好地模拟了块根的生长。通量总和分析表明，两个品种都利用不同的代谢前体在质体中产生能量。KU50 比 HN 更多地将碳通量投入到碳水化合物和氨基酸的合成中。此外，KU50 用于呼吸的通量较少，用于合成一克干块根的能量也较少。这些结果可能揭示了 KU50 更高的块根和淀粉产量背后的代谢潜力。此外，敏感性分析表明 rMeCBM 模型具有稳健性。获得的知识可能有助于确定提高木薯产量的工程目标。
