Du Wen, Song Yajian, Liu Mengya, Yang Haixu, Zhang Yao, Fan Yanli, Luo Xuegang, Li Zhongyuan, Wang Nan, He Hongpeng, Zhou Hao, Ma Wenjian, Zhang Tongcun
College of Biotechnology, Tianjin University of Science and Technology, No. 29, 13th Street, Tianjin Economic and Technological Development Area, Tianjin, 300457, China.
Biotechnol Lett. 2016 Sep;38(9):1571-7. doi: 10.1007/s10529-016-2133-0. Epub 2016 Jul 5.
Escherichia coli K12f-pACLYC has a high capability for growth and lycopene production when using fructose as carbon source and the transcription of genes involved was compared in glucose-grown and fructose-grown cells.
Escherichia coli K12f-pACLYC was grown on 10 g fructose l(-1) and reached 4.6 g DCW l(-1) with lycopene at 192 mg g DCW(-1), values that are 3-fold and 7-fold higher than when growing on glucose. Gene transcription profiles of fructose-grown and glucose-grown cells were compared. 384 differentially expressed genes (DEGs) with fold changes ≥4 were identified, and the transcription of genes involved in fructose uptake and metabolism, pyruvate catabolism, tricarboxylic acid cycle and oxidative phosphorylation varied significantly. These changes enhanced the metabolic flux into the Embden-Meyerhof-Parnas pathway and the tricarboxylic acid cylcle and coupled to oxidative phosphorylation. These enhanced activities provide more precursors, cofactors and energy needed for growth lycopene production.
The high capability of E. coli K12f-pACLYC for growth and lycopene production when growing on fructose is due to transcriptional regulation, and the relevant genes were identified.
当以果糖作为碳源时,大肠杆菌K12f-pACLYC具有很高的生长和番茄红素生产能力,并且对在葡萄糖培养基和果糖培养基中生长的细胞中相关基因的转录情况进行了比较。
大肠杆菌K12f-pACLYC在含有10 g l(-1)果糖的培养基上生长,细胞干重达到4.6 g l(-1),番茄红素含量为192 mg g DCW(-1),这些数值分别比在葡萄糖培养基上生长时高出3倍和7倍。比较了在果糖培养基和葡萄糖培养基中生长的细胞的基因转录谱。鉴定出384个差异表达基因(DEG),其倍数变化≥4,并且参与果糖摄取和代谢、丙酮酸分解代谢、三羧酸循环和氧化磷酸化的基因转录存在显著差异。这些变化增强了进入糖酵解途径和三羧酸循环的代谢通量,并与氧化磷酸化相偶联。这些增强的活性为番茄红素生产提供了生长所需的更多前体、辅因子和能量。
大肠杆菌K12f-pACLYC在果糖培养基上生长时具有很高的生长和番茄红素生产能力,这归因于转录调控,并且已鉴定出相关基因。