Eukaryotic cell and method for producing glycolic acid

Patent metadata

Field	Value
Publication number	US-9783809-B2
Application number	US-201214348902-A
Country	US
Kind code	B2
Filing date	Oct 4, 2012
Priority date	Oct 4, 2011
Publication date	Oct 10, 2017
Grant date	Oct 10, 2017

Abstract

The present invention concerns a eukaryotic host selected from microorganisms, and a method for producing glycolic acid using said eukaryotic host cells, especially cells of a genetically modified fungal host. Further this invention relates to a glycolic acid product obtained using the method described here and the use of genetically modified microorganism cells in production of glycolic acid.

First claim

The invention claimed is:

1. A eukaryotic production host selected from yeast and filamentous fungus cell of species Saccharomyces cerevisiae, Kluveromyces lactis, Candida krusei and Aspergillus niger , wherein the host:
has been genetically modified by transformation of a protein-encoding polynucleotide into the genome of the host cell,
expresses a heterologous gene encoding the glyoxylate reductase of SEQ ID NO: 3, and
produces glycolic acid at a pH of 1.5 to 6.0,

wherein glyoxylate pathway flux has been increased:
a) by overexpressing one or more of the genes selected from isocitrate lyase, fumarate reductase, aconitase, citrate synthase and acetyl-coenzyme A synthetase; or
b) by reducing activity of the enzymes consuming the intermediates of the cycle; or
c) any combination of a) and b).

2. The host of claim 1 , which is capable of producing glycolic acid in non-buffered culturing conditions.

3. The host of claim 1 , wherein the glyoxylate reductase gene encodes a protein having EC number 1.1.1.79 or 1.1.1.26.

4. The host of claim 3 , wherein the cells of the host comprise the genes encoding proteins of SEQ ID NO: 3.

5. A eukaryotic production host selected from yeast and filamentous fungus cell of species Saccharomyces cerevisiae, Kluveromyces lactis, Candida krusei and Aspergillus niger , wherein the host:
has been genetically modified by transformation of a protein-encoding polynucleotide into the genome of the host cell,
expresses a heterologous gene encoding the glyoxylate reductase of SEQ ID NO: 3, and
produces glycolic acid at a pH of 1.5 to 6.0,

wherein glyoxylate cycle regulating gene REG1 has been attenuated or CAT8 has been activated.

6. A eukaryotic production host selected from yeast and filamentous fungus cell of species Saccharomyces cerevisiae, Kluveromyces lactis, Candida krusei and Aspergillus niger , wherein the host:
has been genetically modified by transformation of a protein-encoding polynucleotide into the genome of the host cell,
expresses a heterologous gene encoding the glyoxylate reductase of SEQ ID NO: 3, and
produces glycolic acid at a pH of 1.5 to 6.0,

wherein alcohol production has been reduced by:
a) overexpressing one or more of pyruvate carboxylases; or
b) reducing expression of gene encoding alcohol dehydrogenase.

7. A eukaryotic production host selected from yeast and filamentous fungus cell of species Saccharomyces cerevisiae, Kluveromyces lactis, Candida krusei and Aspergillus niger , wherein the host:
has been genetically modified by transformation of a protein-encoding polynucleotide into the genome of the host cell,
expresses a heterologous gene encoding the glyoxylate reductase of SEQ ID NO: 3, and
produces glycolic acid at a pH of 1.5 to 6.0,

wherein NADPH availability has been improved by overexpressing cytosolic aldehyde dehydrogenase gene or deleting phosphoglucose isomerase gene.

Assignees

• Teknologian Tutkimuskeskus Vtt Oy
• Teknologian Tutkimuskeskus Vtt Oy

Inventors

• Koivistoinen Outi
• Kuivanen Joosu
• Richard Peter
• Penttilä Merja

Classifications

• C12N1/14 Primary

  Fungi (culture of mushrooms A01G18/00; as new plants A01H15/00); Culture media therefor · CPC title

• C12P7/42

  Hydroxy-carboxylic acids · CPC title

• C12N15/52 Primary

  Genes encoding for enzymes or proenzymes · CPC title

• C12N9/0006

  acting on CH-OH groups as donors (1.1) · CPC title

• C12N1/16

  Yeasts; Culture media therefor · CPC title