In silico profiling of Escherichia coli and Saccharomyces cerevisiae as terpenoid factories

Microbial Cell Factories

Research

Evamaria Gruchattka¹  Oliver Kayser¹  Verena Schütz²  Oliver Hädicke³  Steffen Klamt³ 

[1] Department of Biochemical and Chemical Engineering, Technical Biochemistry, TU Dortmund University, Emil-Figge-Str. 66, 44227, Dortmund, Germany;Department of Biochemical and Chemical Engineering, Technical Biochemistry, TU Dortmund University, Emil-Figge-Str. 66, 44227, Dortmund, Germany;Biomax Informatics AG, Robert-Koch-Str. 2, 82152, Planegg, Germany;Max Planck Institute for Dynamics of Complex Technical Systems, Analysis and Redesign of Biological Networks, Sandtorstr. 1, 39106, Magdeburg, Germany;

关键词: Terpenoids;    Isoprenoids;    In silico;    Elementary mode analysis;    Constrained minimal cut sets;    Metabolic engineering;    Escherichia coli;    Saccharomyces cerevisiae;   

DOI  :  10.1186/1475-2859-12-84

 received in 2013-07-02, accepted in 2013-09-15,  发布年份 2013

来源: Springer

【 摘 要 】

BackgroundHeterologous microbial production of rare plant terpenoids of medicinal or industrial interest is attracting more and more attention but terpenoid yields are still low. Escherichia coli and Saccharomyces cerevisiae are the most widely used heterologous hosts; a direct comparison of both hosts based on experimental data is difficult though. Hence, the terpenoid pathways of E. coli (via 1-deoxy-D-xylulose 5-phosphate, DXP) and S. cerevisiae (via mevalonate, MVA), the impact of the respective hosts metabolism as well as the impact of different carbon sources were compared in silico by means of elementary mode analysis. The focus was set on the yield of isopentenyl diphosphate (IPP), the general terpenoid precursor, to identify new metabolic engineering strategies for an enhanced terpenoid yield.ResultsStarting from the respective precursor metabolites of the terpenoid pathways (pyruvate and glyceraldehyde-3-phosphate for the DXP pathway and acetyl-CoA for the MVA pathway) and considering only carbon stoichiometry, the two terpenoid pathways are identical with respect to carbon yield. However, with glucose as substrate, the MVA pathway has a lower potential to supply terpenoids in high yields than the DXP pathway if the formation of the required precursors is taken into account, due to the carbon loss in the formation of acetyl-CoA. This maximum yield is further reduced in both hosts when the required energy and reduction equivalents are considered. Moreover, the choice of carbon source (glucose, xylose, ethanol or glycerol) has an effect on terpenoid yield with non-fermentable carbon sources being more promising. Both hosts have deficiencies in energy and redox equivalents for high yield terpenoid production leading to new overexpression strategies (heterologous enzymes/pathways) for an enhanced terpenoid yield. Finally, several knockout strategies are identified using constrained minimal cut sets enforcing a coupling of growth to a terpenoid yield which is higher than any yield published in scientific literature so far.ConclusionsThis study provides for the first time a comprehensive and detailed in silico comparison of the most prominent heterologous hosts E. coli and S. cerevisiae as terpenoid factories giving an overview on several promising metabolic engineering strategies paving the way for an enhanced terpenoid yield.

【 授权许可】

Unknown   
© Gruchattka et al.; licensee BioMed Central Ltd. 2013. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.