Botany and Microbiology Department, Faculty of Science, Beni-Suef University, Beni-Suef, Egypt.
Biochemistry Division, Chemistry Department, Faculty of Science, Helwan University, Helwan, Egypt.
J Basic Microbiol. 2021 Apr;61(4):330-338. doi: 10.1002/jobm.202000656. Epub 2021 Feb 18.
Microalgae have received continued attention as a potential source for biofuel production. However, the lack of suitable strains that provide a lipid-rich biomass and tolerate harsh condition inhibits their industrial application. This report describes an effort to transform Synechocystis sp. with genes encoding acetyl-CoA carboxylase (ACC), a key regulatory enzyme in the lipogenesis pathway, from the white mustard plant (Sinapis alba) and the bacterium Escherichia coli DH5α using chitosan nanoparticles. Although a recombinant plasmid encoding S. alba ACC failed to express, successful transformation was achieved with a recombinant plasmid encoding E. coli DH5α ACC. The successful transformant, Synechocystis sp. PAK13, exhibited increased ACC expression compared with its wild-type parent (11.8 vs. 7.2 ng), which significantly increased its lipid content (by 3.6-fold). Synechocystis sp. PAK13 also exhibited a significant (20%) reduction in photosynthetic pigments, a 1.52-fold higher glucose content and a 3.5-fold lower sucrose content than the wild-type. In conclusion, this report introduces a useful strategy to overexpress the ACC gene in microalgae, creating strains with improved lipid production that are suited to industrial applications.
微藻作为生物燃料生产的潜在来源一直受到关注。然而，缺乏提供富含脂质的生物质并能耐受恶劣条件的合适菌株，限制了它们的工业应用。本报告描述了使用壳聚糖纳米粒将编码乙酰辅酶 A 羧化酶（ACC）的基因转化入集胞藻（Synechocystis sp.）的尝试，ACC 是脂生成途径中的关键调节酶，该基因来自白芥菜（Sinapis alba）植物和大肠杆菌 DH5α 细菌。尽管编码 S. alba ACC 的重组质粒未能表达，但成功地转化了编码 E. coli DH5α ACC 的重组质粒。与野生型亲本相比，成功转化的集胞藻 PAK13 的 ACC 表达增加了 11.8 倍（ng），这显著增加了其脂质含量（增加了 3.6 倍）。集胞藻 PAK13 的光合色素也显著减少（减少了 20%），葡萄糖含量增加了 1.52 倍，蔗糖含量降低了 3.5 倍。总之，本报告介绍了一种在微藻中过表达 ACC 基因的有用策略，创造了适合工业应用的产脂量提高的菌株。
