The microbial production of chemicals and fuels from plant biomass offers a sustainable alternative to fossilized carbon but requires high rates and yields of bioproduct synthesis. Z. mobilis is a promising chassis microbe due to its high glycolytic rate in anaerobic conditions that are favorable for large-scale production. However, diverting flux from its robust ethanol fermentation pathway to nonnative pathways remains a major engineering hurdle. To enable controlled, high-yield synthesis of bioproducts, we implemented a central-carbon metabolism control-valve strategy using regulated, ectopic expression of pyruvate decarboxylase (Pdc) and deletion of chromosomal pdc. Metabolomic and genetic analyses revealed that glycolytic intermediates and NADH accumulate when Pdc is depleted and that Pdc is essential for anaerobic growth of Z. mobilis. Aerobically, all flux can be redirected to a 2,3-butanediol pathway for which respiration maintains redox balance. Anaerobically, flux can be redirected to redox-balanced lactate or isobutanol pathways with ≥65% overall yield from glucose. This strategy provides a promising path for future metabolic engineering of Z. mobilis.

从植物生物质中微生物生产化学品和燃料是化石碳的可持续替代品，但需要高速率和高产量的生物产品合成。运动发酵单胞菌是一种很有前途的底盘微生物，因为它在厌氧条件下具有高糖酵解速率，有利于大规模生产。然而，将通量从其强大的乙醇发酵途径转移到非天然途径仍然是一个主要的工程障碍。为了实现生物产品的受控、高产合成，我们使用丙酮酸脱羧酶 (Pdc) 的受调控的异位表达和染色体pdc 的缺失实施了中央碳代谢控制阀策略. 代谢组学和遗传分析表明，当 Pdc 耗尽时，糖酵解中间体和 NADH 会积累，并且 Pdc 对运动发酵单胞菌的厌氧生长至关重要。在有氧条件下，所有通量都可以重新定向到 2,3-丁二醇途径，通过该途径呼吸维持氧化还原平衡。在厌氧条件下，通量可以重新定向到氧化还原平衡的乳酸或异丁醇途径，葡萄糖的总产率≥65%。该策略为运动发酵单胞菌的未来代谢工程提供了一条有希望的途径。