Castillo Alfonso Freddy, Vigueras-Ramírez Gabriel, Rosales-Colunga Luis Manuel, Del Monte-Martínez Alberto, Olivares Hernández Roberto
Posgrado en Ciencias Naturales e Ingeniería, Universidad Autónoma Metropolitana, Unidad Cuajimalpa, Av. Vasco de Quiroga 4871, Col. Santa Fe Cuajimalpa, Delegación Cuajimalpa, Ciudad de Mexico, 05348, Mexico.
Departamento de Procesos y Tecnología, Universidad Autónoma Metropolitana, Unidad Cuajimalpa, Av. Vasco de Quiroga 4871, Col. Santa Fe Cuajimalpa, Delegación Cuajimalpa, Ciudad de Mexico, 05348, Mexico.
Mol Omics. 2021 Aug 9;17(4):554-564. doi: 10.1039/d1mo00039j.
3-Indoleacetic acid (IAA) is a phytohormone that promotes plant root growth, improving the use of nutrients and crop yield and it is been reported that bacteria of the genus Bacillus are capable of producing this phytohormone under various growth conditions. Considering this metabolic capability, in this work, Bacillus subtilis was cultivated in five different carbon sources: glucose, acetate, propionate, citrate and glycerol; and l-tryptophan (Trp) was used as an inducer for the IAA production. Based on the experimental results it was observed that the highest growth rate was achieved using glucose as a carbon source (μ = 0.12 h-1) and the lowest value was for citrate (μ = 0.08 h-1). On the other hand, the highest IAA production was obtained using propionate Yp/s = 0.975 (gIAA gTrp-1) and the lowest was when glucose was the substrate Yp/s = 0.803 (gIAA gTrp-1). In order to explore the metabolism and understand these differences, the experimental data was used to calculate the flux distribution using the genomic-scale metabolic model of Bacillus subtilis. Performing a comparative analysis it is observed that the fluxes towards precursors increase when propionate is the carbon source.
3-吲哚乙酸（IAA）是一种植物激素，可促进植物根系生长，提高养分利用率和作物产量。据报道，芽孢杆菌属细菌能够在各种生长条件下产生这种植物激素。考虑到这种代谢能力，在本研究中，枯草芽孢杆菌在五种不同的碳源（葡萄糖、乙酸盐、丙酸盐、柠檬酸盐和甘油）中培养；并使用L-色氨酸（Trp）作为IAA产生的诱导剂。根据实验结果，观察到以葡萄糖作为碳源时生长速率最高（μ = 0.12 h-1），以柠檬酸盐时生长速率最低（μ = 0.08 h-1）。另一方面，以丙酸盐作为底物时IAA产量最高，Yp/s = 0.975（gIAA gTrp-1），以葡萄糖作为底物时IAA产量最低，Yp/s = 0.803（gIAA gTrp-1）。为了探索代谢并理解这些差异，利用枯草芽孢杆菌的基因组规模代谢模型，使用实验数据计算通量分布。通过进行比较分析，观察到当丙酸盐作为碳源时，通向前体的通量增加。
