Method for producing fibroin-like protein

Patent metadata

Field	Value
Publication number	US-9926348-B2
Application number	US-201615356818-A
Country	US
Kind code	B2
Filing date	Nov 21, 2016
Priority date	May 21, 2014
Publication date	Mar 27, 2018
Grant date	Mar 27, 2018

Abstract

A method for producing a fibroin-like protein is described. A fibroin-like protein is produced by culturing Escherichia coli having a gene encoding the fibroin-like protein in a medium, inducing expression of the gene encoding the fibroin-like protein, and collecting the fibroin-like protein, wherein the accumulation of an organic acid at the time of inducing the expression is reduced.

First claim

The invention claimed is:

1. A method for producing a fibroin-like protein, the method comprising:
(A) culturing an Escherichia coli bacterium having a gene encoding the fibroin-like protein in a medium,
(B) inducing expression of the gene encoding the fibroin-like protein while reducing accumulation of an organic acid, and
(C) collecting the fibroin-like protein;
wherein said reducing accumulation of the organic acid is initiated by limiting a carbon source in the medium before inducing the expression, and
wherein the organic acid is selected from the group consisting of acetic acid, citric acid, succinic acid, formic acid, and combinations thereof.

2. The method according to claim 1 , wherein the amount of the organic acid accumulated in the medium during step (B) is 4.5 g/L or less.

3. The method according to claim 1 , wherein the amount of the organic acid, accumulated in the medium during step (B) is 4.0 g/L or less, and wherein said organic acid is acetic acid.

4. The method according to claim 1 , wherein concentration of the carbon source in the medium is 0.5 g/L or lower.

5. The method according to claim 1 , wherein the carbon source is glucose.

6. The method according to claim 1 , wherein said reducing accumulation of the organic acid is further achieved by modifying the Escherichia coli bacterium so that an ability to produce the organic acid is reduced.

7. The method according to claim 1 , wherein said organic acid is acetic acid.

Assignees

• Ajinomoto Kk
• Spiber Inc

Inventors

• Nakase Kentaro

Classifications

• C07K14/43518 Primary

  from spiders · CPC title

• C12R2001/19

  Escherichia coli · CPC title

• C12N15/70 Primary

  Vectors or expression systems specially adapted for E. coli · CPC title

• C12P21/02

  having a known sequence of two or more amino acids, e.g. glutathione · CPC title

• C12N15/09

  Recombinant DNA-technology · CPC title