Towards universal synthetic heterotrophy using a metabolic coordinator.
Towards universal synthetic heterotrophy using a metabolic coordinator.
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使用代谢协调器实现通用合成异养。
DOI：
10.1016/j.ymben.2023.07.001
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发表时间：
2023
影响因子：
8.4
通讯作者：
Nair,NikhilU
中科院分区：
文献类型：
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作者：
Sullivan,SeanF;Shetty,Anuj;Bharadwaj,Tharun;Krishna,Naveen;Trivedi,VikasD;EndalurGopinarayanan,Venkatesh;Chappell,ToddC;Sellers,DanielM;PravinKumar,R;Nair,NikhilU
工程利用非天然底物，或合成异养，在已证实的工业微生物，如酵母菌代表了一个机会，以丰富和可再生的碳和能源作为生物过程的投入。我们以前证明，半乳糖（GAL）调节子，该酵母使用的调节结构，以协调底物利用与生物质形成在半乳糖上生长期间，在非天然底物木糖上生长期间的激活导致基因表达谱的极大改变和与相同异源分解代谢途径的组成型过表达相比更快的生长。然而，这一努力涉及Gal3p（Gal3pSyn4.1）的木糖诱导型变体的产生，Gal3p是GAL调节子的传感器蛋白，防止这种半合成调节子方法容易地适应于另外的非天然底物。在这里，我们报告了一个变体Gal3pMC（metaboliccoordinator）的构建，该变体在结构多样的底物存在下表现出强大的GAL调节子激活，并概括了本机系统的动态。多个分子模拟研究表明，Gal3pMC占据相应的半乳糖结合Gal3p在诱导剂独立的方式构象状态。使用Gal 3pMC测试调节子同化非天然木质纤维素糖木糖、阿拉伯糖和纤维二糖的方法，当与相同组的分解代谢基因的组成性过表达相比时，产生更高的生长速率和最终细胞密度。所有三种非天然底物的快速和完全共利用的随后证明表明，通过GAL调节子活化的Gal3pMC介导的动态全局基因表达变化可能普遍有益于工程化合成异养。
Engineering the utilization of non-native substrates, or synthetic heterotrophy, in proven industrial microbes such asSaccharomyces cerevisiaerepresents an opportunity to valorize plentiful and renewable sources of carbon and energy as inputs to bioprocesses. We previously demonstrated that activation of the galactose (GAL) regulon, a regulatory structure used by this yeast to coordinate substrate utilization with biomass formation during growth on galactose, during growth on the non-native substrate xylose results in a vastly altered gene expression profile and faster growth compared with constitutive overexpression of the same heterologous catabolic pathway. However, this effort involved the creation of a xylose-inducible variant of Gal3p (Gal3pSyn4.1), the sensor protein of the GAL regulon, preventing this semi-synthetic regulon approach from being easily adapted to additional non-native substrates. Here, we report the construction of a variant Gal3pMC(metaboliccoordinator) that exhibits robust GAL regulon activation in the presence of structurally diverse substrates and recapitulates the dynamics of the native system. Multiple molecular modeling studies suggest that Gal3pMCoccupies conformational states corresponding to galactose-bound Gal3p in an inducer-independent manner. Using Gal3pMCto test a regulon approach to the assimilation of the non-native lignocellulosic sugars xylose, arabinose, and cellobiose yields higher growth rates and final cell densities when compared with a constitutive overexpression of the same set of catabolic genes. The subsequent demonstration of rapid and complete co-utilization of all three non-native substrates suggests that Gal3pMC-mediated dynamic global gene expression changes by GAL regulon activation may be universally beneficial for engineering synthetic heterotrophy.