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PGM2 overexpression improves anaerobic galactose fermentation in Saccharomyces cerevisiae

Garcia Sanchez, Rosa LU ; Hahn-Hägerdal, Bärbel LU and Gorwa-Grauslund, Marie-Francoise LU (2010) In Microbial Cell Factories 9(1).
Abstract
BACKGROUND: In Saccharomyces cerevisiae galactose is initially metabolized through the Leloir pathway after which glucose 6-phosphate enters glycolysis. Galactose is controlled both by glucose repression and by galactose induction. The gene PGM2 encodes the last enzyme of the Leloir pathway, phosphoglucomutase 2 (Pgm2p), which catalyses the reversible conversion of glucose 1-phosphate to glucose 6-phosphate. Overexpression of PGM2 has previously been shown to enhance aerobic growth of S. cerevisiae in galactose medium. RESULTS: In the present study we show that overexpression of PGM2 under control of the HXT7'promoter from an integrative plasmid increased the PGM activity 5 to 6 times, which significantly reduced the lag phase of... (More)
BACKGROUND: In Saccharomyces cerevisiae galactose is initially metabolized through the Leloir pathway after which glucose 6-phosphate enters glycolysis. Galactose is controlled both by glucose repression and by galactose induction. The gene PGM2 encodes the last enzyme of the Leloir pathway, phosphoglucomutase 2 (Pgm2p), which catalyses the reversible conversion of glucose 1-phosphate to glucose 6-phosphate. Overexpression of PGM2 has previously been shown to enhance aerobic growth of S. cerevisiae in galactose medium. RESULTS: In the present study we show that overexpression of PGM2 under control of the HXT7'promoter from an integrative plasmid increased the PGM activity 5 to 6 times, which significantly reduced the lag phase of glucose-pregrown cells in an anaerobic galactose culture. PGM2 overexpression also increased the anaerobic specific growth rate whereas ethanol production was less influenced. When PGM2 was overexpressed from a multicopy plasmid instead, the PGM activity increased almost 32 times. However, this increase of PGM activity did not further improve aerobic galactose fermentation as compared to the strain carrying PGM2 on the integrative plasmid. CONCLUSION: PGM2 overexpression in S. cerevisiae from an integrative plasmid is sufficient to reduce the lag phase and to enhance the growth rate in anaerobic galactose fermentation, which results in an overall decrease in fermentation duration. This observation is of particular importance for the future development of stable industrial strains with enhanced PGM activity. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
anaerobic fermentation, galactose, phosphoglucomutase, Saccharomyces cerevisiae, ethanol
in
Microbial Cell Factories
volume
9
issue
1
publisher
BioMed Central
external identifiers
  • wos:000280173400001
  • scopus:77952691597
ISSN
1475-2859
DOI
10.1186/1475-2859-9-40
language
English
LU publication?
yes
id
a1a961bf-0283-4bee-bc01-a1fa85b705c7 (old id 1650884)
alternative location
http://www.microbialcellfactories.com/content/pdf/1475-2859-9-40.pdf
date added to LUP
2010-08-18 11:00:14
date last changed
2018-05-29 11:49:52
@article{a1a961bf-0283-4bee-bc01-a1fa85b705c7,
  abstract     = {BACKGROUND: In Saccharomyces cerevisiae galactose is initially metabolized through the Leloir pathway after which glucose 6-phosphate enters glycolysis. Galactose is controlled both by glucose repression and by galactose induction. The gene PGM2 encodes the last enzyme of the Leloir pathway, phosphoglucomutase 2 (Pgm2p), which catalyses the reversible conversion of glucose 1-phosphate to glucose 6-phosphate. Overexpression of PGM2 has previously been shown to enhance aerobic growth of S. cerevisiae in galactose medium. RESULTS: In the present study we show that overexpression of PGM2 under control of the HXT7'promoter from an integrative plasmid increased the PGM activity 5 to 6 times, which significantly reduced the lag phase of glucose-pregrown cells in an anaerobic galactose culture. PGM2 overexpression also increased the anaerobic specific growth rate whereas ethanol production was less influenced. When PGM2 was overexpressed from a multicopy plasmid instead, the PGM activity increased almost 32 times. However, this increase of PGM activity did not further improve aerobic galactose fermentation as compared to the strain carrying PGM2 on the integrative plasmid. CONCLUSION: PGM2 overexpression in S. cerevisiae from an integrative plasmid is sufficient to reduce the lag phase and to enhance the growth rate in anaerobic galactose fermentation, which results in an overall decrease in fermentation duration. This observation is of particular importance for the future development of stable industrial strains with enhanced PGM activity.},
  articleno    = {40},
  author       = {Garcia Sanchez, Rosa and Hahn-Hägerdal, Bärbel and Gorwa-Grauslund, Marie-Francoise},
  issn         = {1475-2859},
  keyword      = {anaerobic fermentation,galactose,phosphoglucomutase,Saccharomyces cerevisiae,ethanol},
  language     = {eng},
  number       = {1},
  publisher    = {BioMed Central},
  series       = {Microbial Cell Factories},
  title        = {PGM2 overexpression improves anaerobic galactose fermentation in Saccharomyces cerevisiae},
  url          = {http://dx.doi.org/10.1186/1475-2859-9-40},
  volume       = {9},
  year         = {2010},
}