trans‐Cinnamic acid (tCA) can be produced by the deamination of L‐phenylalanine using phenylalanine ammonia‐lyase (PAL). In bioprocesses, optimizing production processes to improve key performance metrics such as titer, rate, and yield has proved challenging. This study investigates tCA production in Pseudomonas putida KT2440 using a whole‐cell biocatalyst expressing four different PAL genes. Among these, RmXAL showed the highest titer and rate. Biocatalysis at pH 8.5 and 37°C were identified as the best conditions, giving a tCA concentration of 2.65 g L−1 and a production rate of 0.44 g L−1 h−1. To improve the metrics further, a decoupled bioprocess with various biocatalyst concentrations in the second stage was examined. With a whole‐cell biocatalyst concentration of 30 gDCW L−1, optimal process parameters were achieved, giving a titer of 29.88 g L−1, rate of 5.99 g L−1 h−1, yield on glucose of 0.27 g tCA g glucose−1, and yield on L‐phe of 0.75 g tCA g L‐phe−1. This study is the first report of a model that enables performance metrics to evaluate a suitable process for tCA production and provides valuable insights into tCA production using a decoupled bioprocess. This would appear applicable to larger‐scale production, paving the way for an efficient and sustainable industrial process.

中文翻译：

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指导微生物生物催化的综合实验和数学建模：恶臭假单胞菌将 L-苯丙氨酸转化为反式肉桂酸


反式肉桂酸 （tCA） 可通过使用苯丙氨酸解氨酶 （PAL） 对 L-苯丙氨酸进行脱氨反应来产生。事实证明，在生物工艺中，优化生产工艺以提高滴度、速率和产量等关键性能指标具有挑战性。本研究使用表达四种不同 PAL 基因的全细胞生物催化剂调查了恶臭假单胞菌 KT2440 中 tCA 的产生。其中，RmXAL 的滴度和速率最高。pH 8.5 和 37°C 的生物催化被确定为最佳条件，tCA 浓度为 2.65 g L-1，生成速率为 0.44 g L-1 h-1。为了进一步改进指标，在第二阶段检查了具有不同生物催化剂浓度的解耦生物过程。当全细胞生物催化剂浓度为 30 gDCW L-1 时，实现了最佳工艺参数，滴度为 29.88 g L-1，速率为 5.99 g L-1 h-1，葡萄糖产量为 0.27 g tCA g 葡萄糖-1，L-phe 产量为 0.75 g tCA g L-phe-1。本研究是模型的第一份报告，该模型使性能指标能够评估适合 tCA 生产的工艺，并为使用解耦生物工艺生产 tCA 提供了有价值的见解。这似乎适用于更大规模的生产，为高效和可持续的工业流程铺平了道路。