A fast-growing and genetically tractable Gram-negative bacterium, E. coli is widely used for recombinant protein expression, metabolite biosynthesis, and synthetic circuit testing. It supports a vast toolbox of promoters, vectors, and gene-editing systems.
As a GRAS-status eukaryotic yeast, S. cerevisiae is ideal for producing proteins requiring complex folding or glycosylation. It offers robust fermentation performance and is extensively used in food, pharma, and bioethanol industries.
This Gram-positive, spore-forming bacterium is ideal for secreting enzymes and other proteins directly into the medium. Its lack of endotoxins and ability to grow in simple media make it attractive for industrial enzyme manufacturing.
Common probiotic strains like Lactobacillus acidophilus are natural inhabitants of the gut and possess excellent safety profiles. Engineered Lactobacillus strains are used in functional food, live biotherapeutics, and microbiome modulation.
Corynebacterium glutamicum
A robust industrial chassis for amino acid and organic acid production, C. glutamicum is non-pathogenic and offers stable, high-yield biosynthetic capabilities under aerobic conditions with low nutritional requirements.
Anaerobic bacteria such as Clostridium butyricum are useful for producing solvents, butyrate, and hydrogen gas. Their unique metabolism enables substrate flexibility and performance in oxygen-free fermentation systems.
Schizosaccharomyces pombe
A model fission yeast used in advanced eukaryotic studies, S. pombe supports precise control over cell cycle, transcriptional regulation, and epigenetics. It is gaining traction in biosynthetic and pharmaceutical applications.
Agrobacterium tumefaciens
Known for horizontal gene transfer in plants, A. tumefaciens is also being explored as a versatile chassis in plant synthetic biology and conjugative expression systems due to its natural transformation efficiency.
Pichia pastoris
Known for its high cell density cultivation and strong, methanol-inducible promoters, P. pastoris excels in secreting heterologous proteins with minimal background. It is widely applied in enzyme, vaccine, and biologic production.
Streptomyces spp.
These soil-dwelling actinobacteria are famous for their secondary metabolite capacity, particularly antibiotics and polyketides. They serve as powerful hosts for heterologous expression of complex natural product pathways.
Fig.1 Chassis strain selection with endogenously expressed OTS1
