Application for the Production of Recombinant Proteins

The starting point for the development of P. pastoris as a protein production system was the discovery that methylotrophic yeasts accumulate large quantities 

Name Relative efficiency Inducing compound References 

As outlined in Section 19.3.1, recombinant protein is either produced in the cytosol or secreted to the culture supernatant when a suitable secretion signal is fused to the 5 end of the gene of interest. The most widely used secretion signal is the mating factor a (MFa) signal of S. cerevisiae, which was shown to 

Name Relative strength Induction strategy References 

Vaoxi library Variants of alcohol oxidase promoter Low to high Methanol addition or constitutive [63] 

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Rice and barley grains are generally regarded as safe for consumption. In many countries, rice flour is the first solid food for infants. Rice-based infant formulas are commercially available and rice is considered hypoallergenic. Thus, cereal grains such as rice are particularly suitable for the production of recombinant protein for oral applications. 

Recently, plant cells have also been considered to be an alternative host for the production of recombinant proteins since they are able to glycosylate proteins [133, 139]. Of the various systems used for cultivation, such as hairy roots, immobilized cells, and free cell suspensions, the latter is regarded to be most suitable for large-scale applications. Full-size antibodies, antibody fragments, and fusion proteins can be expressed in transgenic-plantcell systems, such as Nicotiana tahacum, pea, wheat, and rice using shake-flask or fermentation cultures [136]. Yet, these systems are still of low commercial importance due to their unadvantageous productivity. 

Recombinant baculoviruses and their lepidopteran insect cell hosts have become one of the most widely used expression systems for the production of recombinant proteins [49, 50]. Manipulation of the system is straightforward, and high yields of recombinant material can be readily obtained in a matter of a few weeks compared with the several months that are required with stable animal cell expression systems. Generally, the insect-produced proteins are intended for research applications rather than as pharmaceuticals. The glycans on insect proteins differ significantly from those found on animal cell proteins, and this has limited the development of an attractive expression system for production of human therapeutics. 

In our opinion, the production of recombinant proteins for technical and medical applications should fulfill two main prerequisites. First, it should be possible to produce... 

Many of these properties would obviously limit applicability of non-continuous cell lines in the industrial-scale production of recombinant proteins. However, such cell types are routinely cultured for research purposes, toxicity testing, etc. 

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