Labyrinthulid microorganism capable of producing microbial oil, microbial oil, methods for producing said microorganism and for producing said microbial oil, and uses of said microorganism and said microbial oil

Patent metadata

Field	Value
Publication number	US-11898190-B2
Application number	US-202117401894-A
Country	US
Kind code	B2
Filing date	Aug 13, 2021
Priority date	Jul 3, 2015
Publication date	Feb 13, 2024
Grant date	Feb 13, 2024

Abstract

A method for producing a microbial oil includes steps of: genetically modifying a labyrinthulid by disrupting and/or silencing a gene, or by transforming another gene in addition to the disruption and/or gene silencing of the gene, and culturing the labyrinthulid, such that a fatty acid composition accumulated in the labyrinthulid comprises an increased EPA content; and collecting the microbial oil having the increased EPA content from the labyrinthulid. The labyrinthulid before the modification is selected from (A) a labyrinthulid belonging to the genus Parietichytrium or genus Schizochytrium and having very weak or no activity of producing PUFAs via a PUFA-PKS pathway; and (B) a labyrinthulid belonging to the genus Thraustochytrium in which a host PUFA-PKS gene is disrupted or silenced to a very weak level. The increased EPA content is preferably not less than 11.5% of a total fatty acid composition.

First claim

The invention claimed is:

1. A method for producing a microbial oil, comprising:
genetically modifying a labyrinthulid by disrupting and/or silencing a fatty acid desaturase gene;
culturing the labyrinthulid; and
collecting the microbial oil from the labyrinthulid,
wherein the labyrinthulid before the modification belongs to the genus Parietichytrium or the genus Schizochytrium having an activity of synthesizing DHA via a PUFA-PKS pathway in an amount of not more than 1/100 of a total amount of DHA synthesized in the labyrinthulid or no activity of producing PUFAs via the PUFA-PKS pathway, and having an activity of producing PUFAs via an endogenous elongase-desaturase pathway,
wherein the fatty acid desaturase gene is a Δ4 desaturase gene,
wherein the microbial oil satisfies (a) and (b):
(a) DHA is not greater than 0.50% of the total fatty acid composition; and
(b) a total of DHA and n-6 DPA is not greater than 0.7% of the total fatty acid composition.

2. The method for producing microbial oil according to claim 1 ,
wherein the step of disrupting the gene of the labyrinthulid utilizes electroporation, a gene gun method, or gene editing, and/or wherein the step of gene silencing of a labyrinthulid utilizes an antisense method or RNA interference.

3. The method for producing microbial oil according to claim 1 , wherein the labyrinthulid belonging to the genus Parietichytrium is Parietichytrium sarkarianum , and/or wherein the labyrinthulid belonging to the genus Schizochytrium is Schizochytrium aggregatum.

4. The method for producing microbial oil according to claim 1 ,
wherein the labyrinthulid belonging to the genus Parietichytrium is Parietichytrium sp. SEK358 (FERM BP-11405), Parietichytrium sarkarianum SEK364 (FERM BP-11298), or Parietichytrium sp. SEK571 (FERM BP11406), and/or wherein the labyrinthulid belonging to the genus Schizochytrium is Schizochytrium aggregatum ATCC 28209.

Assignees

• Univ Kyushu Nat Univ Corp
• Konan Gakuen
• Nippon Suisan Kaisha Ltd

Inventors

• Okita Yuji
• Ito Makoto
• Hamaguchi Rie
• Goda Hatsumi
• Mochinaga Seiya
• Honda Daisuke

Classifications

• C12P7/6432 Primary

  Eicosapentaenoic acids [EPA] · CPC title

• C12N15/09

  Recombinant DNA-technology · CPC title

• C12N15/79

  Vectors or expression systems specially adapted for eukaryotic hosts · CPC title

• C12P1/00

  Preparation of compounds or compositions, not provided for in groups C12P3/00 - C12P39/00, by using microorganisms or enzymes · CPC title

• C12P7/64

  Fats; Fatty oils; Ester-type waxes; Higher fatty acids, i.e. having at least seven carbon atoms in an unbroken chain bound to a carboxyl group; Oxidised oils or fats · CPC title