Overexpression of genes involved in phytochelatin biosynthesis in Escherichia coli: effects on growth, cadmium accumulation and thiol level.

• Authors: Anna Wawrzyńska , Adam Wawrzyński , Dali Gaganidze , Edyta Kopera , Katarzyna Piątek , Wojciech Bal , Agnieszka Sirko
• Languages of publication: EN

Abstracts

EN

In Escherichia coli, heterologous production of Schizosaccharomyces pombe phytochelatin synthase (PCS) along with overproduction of E. coli serine acetyltransferase (SAT) and γ-glutamylcysteine synthase (γECS) was achieved and resulted in the accumulation of phytochelatins in bacterial cells. Overproduction of either γECS alone or simultaneous production of all three proteins in bacterial cells were accompanied by reduced growth rate in liquid cultures. Interestingly, bacteria overproducing either γECS or both SAT and γECS (with elevated level of γ-glutamylcysteine but not of phytochelatins) were able to accumulate more cadmium per dry weight than the control. However, the most efficient cadmium accumulation was observed in bacteria with elevated levels of all three proteins: SAT, γECS and PCS. Therefore, "pushing" the entire pathway might be the most promising approach in modification of bacteria for potential bioremediation purposes because the level of intermediates, cysteine and glutathione, can limit the rate of production of phytochelatins. However, in such bacteria other metabolic process might become limiting for efficient growth.

Keywords

EN

cadmium; thiols; phytochelatin; glutathione

• Publisher: Polish Biochemical Society
• Journal: Acta Biochimica Polonica
• Year: 2005
• Volume: 52
• Issue: 1
• Pages: 109-116

Dates

published

2005

received

2004-12-23

accepted

2005-02-18

Contributors

author

Anna Wawrzyńska

• Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warszawa, Poland

author

Adam Wawrzyński

• Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warszawa, Poland

author

Dali Gaganidze

• Scientific Research Center of Agriculture Biotechnology, Tibilisi 380062, Georgia

author

Edyta Kopera

• Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warszawa, Poland

author

Katarzyna Piątek

• Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warszawa, Poland

author

Wojciech Bal

• Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warszawa, Poland

author

Agnieszka Sirko

• Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warszawa, Poland

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