Department of Bioengineering, University of California, San Diego, 9500 Gilman Drive #0412, La Jolla, CA 92093-0412, USA.
Department of Bioengineering, University of California, San Diego, 9500 Gilman Drive #0412, La Jolla, CA 92093-0412, USA; Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kemitorvet, Building 220, DK-2800 Kongens, Lyngby, Denmark.
Metab Eng. 2017 Jan;39:220-227. doi: 10.1016/j.ymben.2016.12.004. Epub 2016 Dec 13.
The metabolic byproducts secreted by growing cells can be easily measured and provide a window into the state of a cell; they have been essential to the development of microbiology, cancer biology, and biotechnology. Progress in computational modeling of cells has made it possible to predict metabolic byproduct secretion with bottom-up reconstructions of metabolic networks. However, owing to a lack of data, it has not been possible to validate these predictions across a wide range of strains and conditions. Through literature mining, we were able to generate a database of Escherichia coli strains and their experimentally measured byproduct secretions. We simulated these strains in six historical genome-scale models of E. coli, and we report that the predictive power of the models has increased as they have expanded in size and scope. The latest genome-scale model of metabolism correctly predicts byproduct secretion for 35/89 (39%) of designs. The next-generation genome-scale model of metabolism and gene expression (ME-model) correctly predicts byproduct secretion for 40/89 (45%) of designs, and we show that ME-model predictions could be further improved through kinetic parameterization. We analyze the failure modes of these simulations and discuss opportunities to improve prediction of byproduct secretion.
生长细胞分泌的代谢副产物很容易被测量到,并且可以提供细胞状态的窗口;这些副产物对微生物学、癌症生物学和生物技术的发展至关重要。通过对细胞进行计算模型的研究,已经可以通过代谢网络的自下而上重建来预测代谢副产物的分泌。然而,由于缺乏数据,这些预测还无法在广泛的菌株和条件下得到验证。通过文献挖掘,我们生成了一个大肠杆菌菌株及其实验测量的代谢副产物分泌数据库。我们在六个历史的大肠杆菌基因组尺度模型中对这些菌株进行了模拟,并报告说随着模型规模和范围的扩大,模型的预测能力也在提高。最新的代谢基因组尺度模型正确预测了 35/89(39%)设计的副产物分泌。下一代代谢和基因表达的基因组尺度模型(ME 模型)正确预测了 40/89(45%)设计的副产物分泌,我们还表明,可以通过动力学参数化进一步改进 ME 模型的预测。我们分析了这些模拟的失败模式,并讨论了改进副产物分泌预测的机会。