Table 8.
Heterologously expressed proteases with (without) the retention of the propeptide.
| Proteases | Protease gene sources | Expression host | Expression with propreptide (Y/N) | Remarks | Reference |
|---|---|---|---|---|---|
| A keratinolytic serine protease | Streptomyces fradiae var.k11 | E. coli | Y | Recombinants expressing the proenzyme exhibited markedly higher activity than that recombinant expressing mature enzyme | Meng et al. (2007) |
| Keratinase | Bacillus licheniformis | Pichia pastoris | Y | Expressing the pro-mature structure was reported to increase the production of the keratinases gene (kerA) | Carlsson et al. (2001) |
| A thermolysin-like neutral protease | Bacillus stearothermophilus | E. coli | N | A much more effective access to active mature protease was found when TLP-ste (devoid of its prosequence) was expressed this confirming that the propeptide is not essential for proper folding of the enzyme or its stabilization during the folding process | Mansfeld et al. (2005) |
| A novel extracellular serine protease | Aeropyrum pernix K1 | E. coli | N | / | Catara et al. (2003) |
| Subtilisin | Thermus thermophilus HB8 | E. coli | Y | Expression of the mature-subtilisin gene was found to produce inactive inclusion bodies, expression of the pro-subtilisin gene resulted in active mature-subtilisin | Xie et al. (2019) |
| Subtilisin E | Bacillus subtilis 168 | E. coli | Y | When the entire coding region for pre-pro-subtilisin E was cloned into an Escherichia coli expression vector, active mature subtilisin E was secreted into the periplasmic space; When the propeptide was absence to the mature subtilisin sequence, no protease activity was detected | Ikemura et al. (1987) |
| Candida secreted aspartic proteases | Candida albicans | Pichia patoris | N | Expression of the C. albicans SAP1 gene lacking the propeptide-coding region in the Pichia pastoris does not lead to the secretion of the enzyme into the culture supernatant, but results in an accumulation of recombinant protein in the cell. Co-expression in this system of the unattached propeptide from Sap1p, as well as from other Saps, restored Sap1p secretion | Beggah et al. (2000) |
| Keratinase | Bacillus licheniformis BBE11-1 | E. coli | Y | Optimizing the C-terminus of propeptide will affect the cleavage efficiency of propeptide. The primary structure of C-terminus propeptide is crucial for the mature keratinase production. | Liu et al. (2014) |
| Leucyl aminopeptidase A | Aspergillus oryzae RIB40 | E. coli and Pichia pastoris | Y | / | Baltulionis et al. (2021) |
| Subtilisin-like serine proteases | Tomato | E. coli | Y | / | Meyer et al. (2016) |
| Nattokinase | Bacillus subtilis VTCC-DVN-12-01 | Bacillus subtilis WB800 | Y | / | Nguyen et al. (2013) |