School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan.
School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan.
J Biosci Bioeng. 2023 Jan;135(1):25-33. doi: 10.1016/j.jbiosc.2022.10.002. Epub 2022 Nov 2.
In this study, Corynebacterium glutamicum was engineered to produce ergothioneine, an amino acid derivative with high antioxidant activity. The ergothioneine biosynthesis genes, egtABCDE, from Mycolicibacterium smegmatis were introduced into wild-type and l-cysteine-producing strains of C. glutamicum to evaluate their ergothioneine production. In the l-cysteine-producing strain, ergothioneine production reached approximately 40 mg L after 2 weeks, and the amount was higher than that in the wild-type strain. As C. glutamicum possesses an ortholog of M. smegmatis egtA, which encodes an enzyme responsible for γ-glutamyl-l-cysteine synthesis, the effect of introducing egtBCDE genes on ergothioneine production in the l-cysteine-producing strain was evaluated, revealing that a further increase to more than 70 mg L was achieved. As EgtBs from Methylobacterium bacteria are reported to use l-cysteine as a sulfur donor in ergothioneine biosynthesis, egtB from Methylobacterium was expressed with M. smegmatis egtDE in the l-cysteine-producing strain. As a result, ergothioneine production was further improved to approximately 100 mg L. These results indicate that utilization of the l-cysteine-producing strain and introduction of heterologous biosynthesis pathways from M. smegmatis and Methylobacterium bacteria are effective for improved ergothioneine production by C. glutamicum.
在这项研究中，我们对谷氨酸棒杆菌进行了工程改造，以生产具有高抗氧化活性的氨基酸衍生物——麦硫因。我们从耻垢分枝杆菌中引入了麦硫因生物合成基因 egtABCDE，将其导入野生型和产 L-半胱氨酸的谷氨酸棒杆菌菌株中，以评估它们的麦硫因生产能力。在产 L-半胱氨酸的菌株中，经过 2 周的培养，麦硫因的产量约为 40mg/L，高于野生型菌株。由于谷氨酸棒杆菌具有与耻垢分枝杆菌 egtA 同源的基因，该基因编码一种负责 γ-谷氨酰-L-半胱氨酸合成的酶，因此我们评估了在产 L-半胱氨酸的菌株中引入 egtBCDE 基因对麦硫因生产的影响，结果发现产量进一步提高到了 70mg/L 以上。由于报道称甲基杆菌中的 EgtBs 在麦硫因生物合成中使用 L-半胱氨酸作为硫供体，因此我们在产 L-半胱氨酸的菌株中表达了来自甲基杆菌的 egtB 与耻垢分枝杆菌的 egtDE。结果，麦硫因的产量进一步提高到了约 100mg/L。这些结果表明，利用产 L-半胱氨酸的菌株并引入来自耻垢分枝杆菌和甲基杆菌的异源生物合成途径，可有效提高谷氨酸棒杆菌的麦硫因产量。
