US 10,544,435 B2Granted

L-ornithine production in eukaryotic cells

AssigneeChrysea Limited

InventorsJiufu Qin, Anastasia Krivoruchko, Florian David, Bo Jiang, Jens Nielsen

Life of this patent

Estimating the term…

Loading patent…

Abstract

The present invention relates to the provision of genetically modified microbial cells, such as yeast cells with an improved ability for producing L-ornithine and its derivatives. Overproduction of L-ornithine is obtained in the first place by the down-regulation or attenuation of specially selected genes, wherein said genes encode enzymes involved in the L-ornithine consumption and/or degradation pathways. Further L-ornithine production ability is improved by down-regulation, attenuation, deletion or overexpression of specially selected genes, wherein said genes encode enzymes and/or proteins involved in the L-ornithine ‘acetylated derivatives cycle’, L-glutamate synthesis pathways, subcellular trafficking, TCA cycle, pyruvate carboxylation pathway, respiratory electron-transport chain, and the carbon substrates' assimilation machinery. The invention additionally provides a method to produce L-ornithine with said modified eukaryotic cells.

Claims24

Dependent claims

A genetically modified fungal cell modified for enhanced L-ornithine biosynthesis from α-ketoglutarate, wherein

(1) the L-ornithine biosynthesis from α-ketoglutarate is cytosolic and the fungal cell is modified to comprise at least one of the genes selected from a group consisting of:
(a) a gene encoding a cytosolic glutamate N-acetyltransferase (EC 2.3.1.1);
(b) a gene encoding a cytosolic N-acetylglutamate kinase (EC 2.7.2.8);
(c) a gene encoding a cytosolic N-acetyl-gamma-glutamyl-phosphate reductase (EC.1.2.1.38);
(d) a gene encoding a cytosolic acetylornithine aminotransferase (EC 2.6.1.11);
and
(e) a gene encoding a cytosolic ornithine acetyltransferase (EC 2.3.1.35);
or
(2) the genetically modified fungal cell is genetically modified for overexpression of L-ornithine transporter of the mitochondrial inner membrane and/or for overexpression of L-glutamate transporter;
and for overexpression of:
(a) a gene encoding an N-acetylglutamate kinase (EC 2.7.2.8) and N-acetyl-gamma-glutamyl-phosphate reductase (EC.1.2.1.38);
(b) a gene encoding a mitochondrial ornithine acetyltransferase (EC 2.3.1.35);
(c) a gene encoding an acetylornithine aminotransferase (EC 2.6.1.11);
and
(d) a gene encoding an acetylglumate synthase (EC 2.3.1.1).

12 more elements

Dependencies are inferred from the claim text.

Facts

Application: 15/556,737Filed 10 Mar 2016 · us provisional application
Priority: 12 Mar 2015
Published: US 2018/0105850 A119 Apr 2018
Granted: 28 Jan 2020
Term ends: Not estimatedThe source records don’t support an estimate.

Classification19 codes

C12P 13/10
Alpha- or beta- amino acids: citrulline; Arginine; Ornithine
C12N 9/0008
Oxidoreductases: acting on the aldehyde or oxo group of donors
C12N 9/1018
Transferring one-carbon groups: carboxy- and carbamoyl transferases
C12N 9/1096
Transferases: transferring nitrogenous groups

Family

Application62/132,349Us provisional application · filed 12 Mar 2015
Application62/166,050Us provisional application · filed 25 May 2015
US 2018/0105850 A1Pre-grant publication · published 19 Apr 2018
US 10,544,435 B2This patent

From the US filing history. Foreign family members aren’t listed.