The Genetic Landscape of a Metabolic Interaction.
The Genetic Landscape of a Metabolic Interaction.
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代谢相互作用的遗传景观。
DOI：
10.1101/2023.05.28.542639
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发表时间：
2023
期刊：
影响因子：
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通讯作者：
Reynolds,KimberlyA
中科院分区：
文献类型：
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作者：
Nguyen,ThuyN;Ingle,Christine;Thompson,Samuel;Reynolds,KimberlyA
虽然许多先前的工作已经探索了物理蛋白质-蛋白质相互作用引起的蛋白质序列和进化的限制，但代谢中非结合功能相互作用所产生的序列水平限制仍不清楚。为了量化一种酶活性的变化如何限制另一种酶的生化参数和序列，我们重点关注二氢叶酸还原酶（DHFR）和胸苷酸合酶（TYMS），这是一对催化叶酸代谢中连续反应的酶。我们使用深度突变扫描来量化 3 个 TYMS 背景中 2696 个 DHFR 单突变在强调生化上位性的条件下的生长率效应。我们的数据通过相对简单的酶生长速率模型得到了很好的描述，该模型量化了代谢背景如何调整酶突变耐受性。我们的结果共同揭示了代谢酶中上位性的结构分布，并为多酶系统的设计奠定了基础。
While much prior work has explored the constraints on protein sequence and evolution induced by physical protein-protein interactions, the sequence-level constraints emerging from non-binding functional interactions in metabolism remain unclear. To quantify how variation in the activity of one enzyme constrains the biochemical parameters and sequence of another, we focus on dihydrofolate reductase (DHFR) and thymidylate synthase (TYMS), a pair of enzymes catalyzing consecutive reactions in folate metabolism. We use deep mutational scanning to quantify the growth rate effect of 2696 DHFR single mutations in 3 TYMS backgrounds under conditions selected to emphasize biochemical epistasis. Our data are well-described by a relatively simple enzyme velocity to growth rate model that quantifies how metabolic context tunes enzyme mutational tolerance. Together our results reveal the structural distribution of epistasis in a metabolic enzyme and establish a foundation for the design of multi-enzyme systems.