Masuo Shunsuke, Saga Chisa, Usui Kurumi, Sasakura Yuma, Kawasaki Yukie, Takaya Naoki
Faculty of Life and Environmental Sciences, Microbiology Research Center for Sustainability, University of Tsukuba, Tsukuba, Japan.
Front Bioeng Biotechnol. 2022 Feb 14;10:843843. doi: 10.3389/fbioe.2022.843843. eCollection 2022.
The demand for raspberry ketone (RK) as a plant-based natural flavoring agent is high, but natural RK is one of the most expensive flavor compounds due to its limited content in plants. Here, we produced RK from simple carbon sources in We genetically engineered metabolism to overproduce the metabolic precursors tyrosine and -coumaric acid and increase RK production. The engineered produced 19.3- and 1.9 g/L of tyrosine and -coumaric acid from glucose, respectively. The -coumaric acid CoA ligase from and amino acid substituted benzalacetone synthase of (Chinese rhubarb) were overexpressed in overproducing -coumaric acid The overexpression of , encoding β-ketoacyl-acyl carrier protein synthetase II increased intracellular malonyl-CoA, the precursor of benzalacetone synthase for RK biosynthesis, and improved RK production. Fed-batch cultures given glucose as a carbon source produced 62 mg/L of RK under optimized conditions. Our production system is inexpensive and does not rely on plant extraction; thus, it should significantly contribute to the flavor and fragrance industries.
对树莓酮（RK）作为一种植物源天然调味剂的需求很高，但天然RK因其在植物中的含量有限，是最昂贵的调味化合物之一。在此，我们利用简单碳源在[具体微生物名称未给出]中生产RK。我们对其代谢进行基因工程改造，以过量生产代谢前体酪氨酸和对香豆酸，并提高RK产量。工程菌分别从葡萄糖中产生了19.3克/升和1.9克/升的酪氨酸和对香豆酸。来自[具体微生物名称未给出]的对香豆酸辅酶A连接酶和[中国大黄]的氨基酸取代苯甲酰丙酮合酶在过量生产对香豆酸的[具体微生物名称未给出]中过表达。编码β-酮酰-酰基载体蛋白合成酶II的[具体基因名称未给出]的过表达增加了细胞内丙二酰辅酶A，这是RK生物合成中苯甲酰丙酮合酶的前体，并提高了RK产量。在优化条件下，以葡萄糖作为碳源的补料分批培养产生了62毫克/升的RK。我们的生产系统成本低廉，不依赖植物提取；因此，它应为香料和香精行业做出重大贡献。
