Limits...
Cheese whey-induced high-cell-density production of recombinant proteins in Escherichia coli.

Viitanen MI, Vasala A, Neubauer P, Alatossava T - Microb. Cell Fact. (2003)

Bottom Line: Addition of yeast extract or proteolytically degraded whey proteins did not improve the recombinant protein yield.In contrast, addition of yeast extract to the well-balanced mineral salt medium decreased the product yield.In low-cell-density shake flask experiments the yield was higher with whey or whey permeate than with IPTG.

View Article: PubMed Central - HTML - PubMed

Affiliation: Bioprocess Engineering Laboratory, Department of Process and Environmental Engineering, Biocenter Oulu, University of Oulu, FIN-90014, Oulu, Finland. antti.vasala@oulu.fi

ABSTRACT
BACKGROUND: Use of lactose-rich concentrates from dairy processes for the induction of recombinant gene's expression has not received much attention although they are interesting low cost substrates for production of recombinant enzymes. Applicability of dairy waste for induction of recombinant genes in Escherichia coli was studied. Clones expressing Lactobacillus phage muramidase and Lactobacillus alcohol dehydrogenase were used for the experiments. RESULTS: Shake flask cultivations in mineral salt medium showed that cheese whey or deproteinised whey induced gene expression as efficiently as IPTG (isopropyl-beta-D-thiogalactopyranoside) or pure lactose. Addition of yeast extract or proteolytically degraded whey proteins did not improve the recombinant protein yield. In contrast, addition of yeast extract to the well-balanced mineral salt medium decreased the product yield. Feeding with glycerol provided sufficient amount of easily assimilable carbon source during the induction period without preventing lactose intake and induction by lactose. High-cell-density fed-batch cultivations showed that product yields comparable to IPTG-induction can be achieved by feeding bacteria with a mixture of glycerol and concentrated whey permeate during the induction. CONCLUSION: Whey and concentrated whey permeate can be applied as an alternative inducer in recombinant high-cell-density fed-batch fermentations. The yield of the recombinant product was comparable to fermentations induced by IPTG. In low-cell-density shake flask experiments the yield was higher with whey or whey permeate than with IPTG.

No MeSH data available.


Related in: MedlinePlus

Fermentation conditions during fed-batch production of Adh by E. coli. Start of induction by addition of concentrated whey permeate/glycerol mixture (first broken line) and time point for increase in feed rate (second broken line) are shown.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC155635&req=5

Figure 4: Fermentation conditions during fed-batch production of Adh by E. coli. Start of induction by addition of concentrated whey permeate/glycerol mixture (first broken line) and time point for increase in feed rate (second broken line) are shown.

Mentions: The competitiveness of CWP induction compared to IPTG-induction was also tested in high-cell-density fermentations for production of Adh in E. coli RB791 pQE30Adh. In contrast to mur expression the adh gene product is non-toxic for the host allowing to be accumulated to more than 50% of the total cell protein after induction with IPTG. The fed-batch growth with glucose feeding (see Materials and methods) was followed by induction with a) 0.5 mM IPTG (constant feed of glucose, not shown) or b) with the CWP/glycerol mixture (Fig. 4).


Cheese whey-induced high-cell-density production of recombinant proteins in Escherichia coli.

Viitanen MI, Vasala A, Neubauer P, Alatossava T - Microb. Cell Fact. (2003)

Fermentation conditions during fed-batch production of Adh by E. coli. Start of induction by addition of concentrated whey permeate/glycerol mixture (first broken line) and time point for increase in feed rate (second broken line) are shown.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC155635&req=5

Figure 4: Fermentation conditions during fed-batch production of Adh by E. coli. Start of induction by addition of concentrated whey permeate/glycerol mixture (first broken line) and time point for increase in feed rate (second broken line) are shown.
Mentions: The competitiveness of CWP induction compared to IPTG-induction was also tested in high-cell-density fermentations for production of Adh in E. coli RB791 pQE30Adh. In contrast to mur expression the adh gene product is non-toxic for the host allowing to be accumulated to more than 50% of the total cell protein after induction with IPTG. The fed-batch growth with glucose feeding (see Materials and methods) was followed by induction with a) 0.5 mM IPTG (constant feed of glucose, not shown) or b) with the CWP/glycerol mixture (Fig. 4).

Bottom Line: Addition of yeast extract or proteolytically degraded whey proteins did not improve the recombinant protein yield.In contrast, addition of yeast extract to the well-balanced mineral salt medium decreased the product yield.In low-cell-density shake flask experiments the yield was higher with whey or whey permeate than with IPTG.

View Article: PubMed Central - HTML - PubMed

Affiliation: Bioprocess Engineering Laboratory, Department of Process and Environmental Engineering, Biocenter Oulu, University of Oulu, FIN-90014, Oulu, Finland. antti.vasala@oulu.fi

ABSTRACT
BACKGROUND: Use of lactose-rich concentrates from dairy processes for the induction of recombinant gene's expression has not received much attention although they are interesting low cost substrates for production of recombinant enzymes. Applicability of dairy waste for induction of recombinant genes in Escherichia coli was studied. Clones expressing Lactobacillus phage muramidase and Lactobacillus alcohol dehydrogenase were used for the experiments. RESULTS: Shake flask cultivations in mineral salt medium showed that cheese whey or deproteinised whey induced gene expression as efficiently as IPTG (isopropyl-beta-D-thiogalactopyranoside) or pure lactose. Addition of yeast extract or proteolytically degraded whey proteins did not improve the recombinant protein yield. In contrast, addition of yeast extract to the well-balanced mineral salt medium decreased the product yield. Feeding with glycerol provided sufficient amount of easily assimilable carbon source during the induction period without preventing lactose intake and induction by lactose. High-cell-density fed-batch cultivations showed that product yields comparable to IPTG-induction can be achieved by feeding bacteria with a mixture of glycerol and concentrated whey permeate during the induction. CONCLUSION: Whey and concentrated whey permeate can be applied as an alternative inducer in recombinant high-cell-density fed-batch fermentations. The yield of the recombinant product was comparable to fermentations induced by IPTG. In low-cell-density shake flask experiments the yield was higher with whey or whey permeate than with IPTG.

No MeSH data available.


Related in: MedlinePlus