Engineering and systems-level analysis of Saccharomyces cerevisiae for production of 3-hydroxypropionic acid via malonyl-CoA reductase-dependent pathway
Artikel i vetenskaplig tidskrift, 2016

Background: In the future, oil-and gas-derived polymers may be replaced with bio-based polymers, produced from renewable feedstocks using engineered cell factories. Acrylic acid and acrylic esters with an estimated world annual production of approximately 6 million tons by 2017 can be derived from 3-hydroxypropionic acid (3HP), which can be produced by microbial fermentation. For an economically viable process 3HP must be produced at high titer, rate and yield and preferably at low pH to minimize downstream processing costs. Results: Here we describe the metabolic engineering of baker's yeast Saccharomyces cerevisiae for biosynthesis of 3HP via a malonyl-CoA reductase (MCR)-dependent pathway. Integration of multiple copies of MCR from Chloroflexus aurantiacus and of phosphorylation-deficient acetyl-CoA carboxylase ACC1 genes into the genome of yeast increased 3HP titer fivefold in comparison with single integration. Furthermore we optimized the supply of acetyl-CoA by overexpressing native pyruvate decarboxylase PDC1, aldehyde dehydrogenase ALD6, and acetyl-CoA synthase from Salmonella enterica SEacsL641P. Finally we engineered the cofactor specificity of the glyceraldehyde-3-phosphate dehydrogenase to increase the intracellular production of NADPH at the expense of NADH and thus improve 3HP production and reduce formation of glycerol as by-product. The final strain produced 9.8 +/- 0.4 g L-1 3HP with a yield of 13 % C-mol C-mol(-1) glucose after 100 h in carbon-limited fed-batch cultivation at pH 5. The 3HP-producing strain was characterized by C-13 metabolic flux analysis and by transcriptome analysis, which revealed some unexpected consequences of the undertaken metabolic engineering strategy, and based on this data, future metabolic engineering directions are proposed. Conclusions: In this study, S. cerevisiae was engineered for high-level production of 3HP by increasing the copy numbers of biosynthetic genes and improving flux towards precursors and redox cofactors. This strain represents a good platform for further optimization of 3HP production and hence an important step towards potential commercial bio-based production of 3HP.

escherichia-coli

Metabolic engineering

genes

reveals

Redox metabolism

chemicals

3-Hydroxypropionic acid

yeast

Saccharomyces cerevisiae

growth

increases

flux analysis

mutations

deletion

Författare

K. R. Kildegaard

Danmarks Tekniske Universitet (DTU)

N. B. Jensen

Evolva Biotech

Danmarks Tekniske Universitet (DTU)

K. Schneider

Danmarks Tekniske Universitet (DTU)

E. Czarnotta

RWTH Aachen University

E. Ozdemir

Danmarks Tekniske Universitet (DTU)

T. Klein

Danmarks Tekniske Universitet (DTU)

J. Maury

Danmarks Tekniske Universitet (DTU)

B. E. Ebert

RWTH Aachen University

H. B. Christensen

Danmarks Tekniske Universitet (DTU)

Yun Chen

Chalmers, Biologi och bioteknik, Systembiologi

Il-Kwon Kim

Chalmers, Biologi och bioteknik, Systembiologi

M. J. Herrgard

Danmarks Tekniske Universitet (DTU)

L. M. Blank

RWTH Aachen University

J. Forster

Danmarks Tekniske Universitet (DTU)

Jens B Nielsen

Chalmers, Biologi och bioteknik, Systembiologi

I. Borodina

Danmarks Tekniske Universitet (DTU)

Microbial Cell Factories

1475-2859 (ISSN)

Vol. 15 53 53

Ämneskategorier

Biologiska vetenskaper

Styrkeområden

Energi

Livsvetenskaper och teknik

DOI

10.1186/s12934-016-0451-5