Table 3 Production of 5-ALA via C5 pathway in E. coli
Year | Strain | Strategy | ALA titer (g/L) | ALA productivity (g/L/h) | Ref |
|---|---|---|---|---|---|
2011 | DH5a | Expressing hemA from S. Arizona and identify exporter RhtA for ALA | 4.13 | 0.086 | |
2014 | DH5a | Using small RNA ryhB to enhance ALA production | 1.5 | 0.047 | Li et al. (2014) |
2015 | BL21(DE3) | Identify the relation of ALA production and genes on heme synthesis pathway, combinatorial over-express hemA, hemL, hemD, and hemF with different copy-number plasmids | 3.25 | 0.108 | Zhang et al. (2015) |
2015 | BL21(DE3) | Co-overexpression of the heme synthesis pathway genes hemA, hemL, hemF, and hemD with the addition of 7.5Â mg/L iron | 4.05 | 0.127 | Zhang et al. (2016) |
2017 | W (ATCC9637) | Applying synthetic and strong promoter for hemA from S. typhimurium and hemL, deletion of sucA and fine-tune gltA and aceA level | 3.4 | 0.189 | Noh et al. (2017) |
2019 | BL21(DE3) | Optimize hemA and hemL level with RBS engineering, weaken hemB, and strengthen pdxH for PLP synthesis. Finally improve the production in 3-L fermenter | 5.25 | 0.146 | Zhang et al. (2019) |
2019 | DH5a | Fine-tuning hemB by CRISPRi system at various targeting sites and using fed-batch fermentation | 1.99 | 0.046 | Su et al. (2019) |
2019 | MG1655 | Integrating multiple copies of hemA-hemL by CIChE in DrecA strain | 4.55 | 0.063 | Cui et al. (2019) |
2019 | Transetta(DE3) | Expressing hemA1 (GTR) and pgr7 (GBP) genes from Arabidopsis thaliana | 7.64 | 0.159 | Aiguo and Meizhi (2019) |
2020 | DH5α | A heme-responsive regulatory system containing a heme biosensor HrtR and CRISPRi was designed to regulate chemicals production while maintaining the intracellular heme homeostasis | 5.35 | 0.111 | Zhang et al. (2020a) |