On-line specific growth rate control for improving reduced glutathione production in Saccharomyces cerevisiae

This contribution discusses the main challenges related to successful application of automatic control systems used to control specific growth rate in industrial biotechnological processes. It is emphasized that, after the implementation of basic automatic control systems, primary attention shall be paid to the specific growth rate control systems because this process variable critically affects the physiological state of microbial cultures and the formation of the desired product. Therefore, control of the specific growth rate enables improvement of the quality and reproducibility of the biotechnological processes. The main requirements have been formulated that shall be met to successfully implement the specific growth rate control systems in industrial bioreactors. The relatively easy-to-implement schemes of specific growth rate control systems have been reviewed and discussed. The recommendations for selection of particular control systems for specific biotechnological processes have been provided.

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Sliding mode scheme for adaptive specific growth rate control in biotechnological fed-batch processes

International Journal of Control ◽

10.1080/002071705000073772 ◽

2005 ◽

Vol 78 (2) ◽

pp. 128-141 ◽

Cited By ~ 29

Author(s):

E. Picó-Marco ◽

J. Picó * ◽

H. De Battista

Keyword(s):

Growth Rate ◽

Specific Growth Rate ◽

Rate Control ◽

Specific Growth ◽

Sliding Mode ◽

Batch Processes ◽

Fed Batch ◽

Growth Rate Control

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Influence of organic acids and organochlorinated insecticides on metabolism of Saccharomyces cerevisiae

Zbornik Matice srpske za prirodne nauke ◽

10.2298/zmspn0508207p ◽

2005 ◽

pp. 207-215 ◽

Cited By ~ 1

Author(s):

Dusanka Pejin ◽

Vesna Vasic

Keyword(s):

Saccharomyces Cerevisiae ◽

Growth Rate ◽

Sugar Beet ◽

Specific Growth Rate ◽

Glycogen Content ◽

Specific Growth ◽

Raw Materials ◽

Stress Factors ◽

Adaptive Mechanism ◽

Ribonucleic Acids

Saccharomyces cerevisiae is exposed to different stress factors during the production: osmotic, temperature, oxidative. The response to these stresses is the adaptive mechanism of cells. The raw materials Saccharomyces cerevisiae is produced from, contain metabolism products of present microorganisms and protective agents used during the growth of sugar beet for example the influence of acetic and butyric acid and organochlorinated insecticides, lindan and heptachlor, on the metabolism of Saccharomyces cerevisiae was investigated and presented in this work. The mentioned compounds affect negatively the specific growth rate, yield, content of proteins, phosphorus, total ribonucleic acids. These compounds influence the increase of trechalose and glycogen content in the Saccharomyces cerevisiae cells.

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Anaplerotic reactions active during growth of Saccharomyces cerevisiae on glycerol

FEMS Yeast Research ◽

10.1093/femsyr/foz086 ◽

2019 ◽

Vol 20 (1) ◽

Cited By ~ 1

Author(s):

Joeline Xiberras ◽

Mathias Klein ◽

Celina Prosch ◽

Zahabiya Malubhoy ◽

Elke Nevoigt

Keyword(s):

Saccharomyces Cerevisiae ◽

Growth Rate ◽

Specific Growth Rate ◽

Pyruvate Carboxylase ◽

Reference Strain ◽

Specific Growth ◽

Glyoxylate Cycle ◽

Maximum Specific Growth Rate ◽

The Glyoxylate Cycle ◽

Anaplerotic Reactions

ABSTRACT Anaplerotic reactions replenish TCA cycle intermediates during growth. In Saccharomyces cerevisiae, pyruvate carboxylase and the glyoxylate cycle have been experimentally identified to be the main anaplerotic routes during growth on glucose (C6) and ethanol (C2), respectively. The current study investigates the importance of the two isoenzymes of pyruvate carboxylase (PYC1 and PYC2) and one of the key enzymes of the glyoxylate cycle (ICL1) for growth on glycerol (C3) as a sole carbon source. As the wild-type strains of the CEN.PK family are unable to grow in pure synthetic glycerol medium, a reverse engineered derivative showing a maximum specific growth rate of 0.14 h−1 was used as the reference strain. While the deletion of PYC1 reduced the maximum specific growth rate by about 38%, the deletion of PYC2 had no significant impact, neither in the reference strain nor in the pyc1Δ mutant. The deletion of ICL1 only marginally reduced growth of the reference strain but further decreased the growth rate of the pyc1 deletion strain by 20%. Interestingly, the triple deletion (pyc1Δ pyc2Δ icl1Δ) did not show any growth. Therefore, both the pyruvate carboxylase and the glyoxylate cycle are involved in anaplerosis during growth on glycerol.

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