Combinatorial metabolic engineering platform enabling stable overproduction of lycopene from carbon dioxide by cyanobacteria
Combinatorial metabolic engineering platform enabling stable overproduction of lycopene from carbon dioxide by cyanobacteria
复制标题
组合代谢工程平台可实现蓝藻从二氧化碳中稳定过量生产番茄红素
DOI：
10.1101/2020.03.11.983833
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发表时间：
2020
期刊：
影响因子：
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通讯作者：
Taylor G
中科院分区：
文献类型：
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作者：
Taylor G
蓝藻是一种简单、高效、遗传上易处理的光合微生物，是CO2捕获和转化的理想生物催化剂。在实践中，遗传不稳定性和低生产力是工程蓝藻的关键，相关的问题。我们采取了大规模并行的方法，生成和表征蓝细菌集胞藻的合成启动子和RBS库，并组装了数百万个代谢途径编码构建变体的稀疏组合库。实验室进化抑制了引起集胞藻代谢负担的变体，导致预期的遗传不稳定性。然而，令人惊讶的是，在没有迭代优化的单个组合轮中，随机选择的80%的变体在许多代中从大气CO2中过量产生有价值的萜类番茄红素，显然克服了稳定性和生产力之间的权衡。这种首次大规模并行的蓝藻代谢工程为开发遗传稳定的蓝藻生物催化剂提供了一个新的平台，用于直接从CO2中可持续地光驱动生产有价值的产品，避免化石碳或与粮食生产竞争。
Cyanobacteria are simple, efficient, genetically-tractable photosynthetic microorganisms representing ideal biocatalysts for CO2capture and conversion, in principle. In practice, genetic instability and low productivity are key, linked problems in engineered cyanobacteria. We took a massively parallel approach, generating and characterising libraries of synthetic promoters and RBSs for the cyanobacteriumSynechocystis, and assembling a sparse combinatorial library of millions of metabolic pathway-encoding construct variants. Laboratory evolution suppressed variants causing metabolic burden inSynechocystis, leading to expected genetic instability. Surprisingly however, in a single combinatorial round without iterative optimisation, 80% of variants chosen at random overproduced the valuable terpenoid lycopene from atmospheric CO2over many generations, apparently overcoming the trade-off between stability and productivity. This first large-scale parallel metabolic engineering of cyanobacteria provides a new platform for development of genetically stable cyanobacterial biocatalysts for sustainable light-driven production of valuable products directly from CO2, avoiding fossil carbon or competition with food production.