30 results about "Fumarase" patented technology

The invention provides a construction method for producing fumaric acid based on pichia stipitis synthetic strain fermented xylose. The method comprises the following steps: using pichia stipitis having a natural xylose metabolic capability as a host; deleting genes PSfum1 and PSfum2 that encode fumarase in tricarboxylic acid cycle of pichia stipitis, to acquire fumarase deficient mutants; heterologously expressing a modified fumaric reduction synthesis module on the basis of the acquired mutants, using xylose to ferment yeast synthesis strains of fumaric acid; on the basis of the yeast synthesis strains, expressing translocator YMAE that is modified with codons and originated from Chestnut wine fission yeasts, to acquire pichia stipitis synthesis strains for producing fumaric acid by fermented xylose; efficiently fermenting the acquired strains in a fully synthesized fermentation culture medium to produce fumaric acid by fermentation of xylose; cultivating by fermentation for 3-4 days at a temperature of 30 degrees centigrade with a stirring speed of 150-200rpm. The content of fumaric acid is greater than 4g / L.

The present invention relates to a mutant organism having the ability to produce aspartic acid derivatives, wherein a gene encoding the glyoxylate shunt regulator and a gene encoding fumarase are deleted and a gene encoding aspartase is overexpressed compared to that in a wild-type strain, and to a method for producing L-aspartic acid derivatives using the same. According to the present invention, various aspartic acid derivatives, including L-alanine, 3-aminopropionic acid, threonine, 1,3-diaminopropane, lysine, methionine, 3-hydroxypropionic acid, cadaverine, 5-aminovaleric acid, etc., can be produced by biological methods.

The present invention discloses a fumarase mutant and application thereof. The fumarase mutant of SEQ ID NO: 4 derived from Sulfolobus solfataricus P2 is obtained by a directed evolution method, the mutant or expression microorganisms thereof is capable of catalyzing a hydration reaction of crotonic acid to prepare (R)-3-hydroxybutyric acid, the product ee value exceeds 95%, and the fumarase mutant has industrial development and application prospects.

The invention relates to a method for producing malic acid by fermentation of citric acid mother liquor. In the method, with the citric acid mother liquor as a carbon source, a strain capable of producing fumarase by fermentation produces fumarase, and fermentation liquor is used as a raw material to convert sodium fumarate. After 20 to 25 hours of conversion, the content of L-malic acid reaches about 1.1 mol / L, and the conversion rate is about 94 percent. In the invention, performed separately, the fumarase production and conversion both can be performed under more proper conditions; the process is simple; energy consumption is small; the raw material is cheap; and the substrate conversion rate is high.

The invention provides a method for improving efficiency of escherichia coli on synthesizing fumaric acid. Specificity labels are added on two ends of three key enzymes (pyruvate dehydrogenase, malic dehydrogenase and fumarase) synthesized by the fumaric acid, so that covalent binding of the three enzymes is realized, a substrate channel is shortened, and the synthetic efficiency of the fumaric acid in the escherichia coli is promoted.

The invention provides a gene engineering bacterial strain for producing L-malic acid as well as a construction method and application thereof. In the invention, key phosphoenolpyruvate carboxykinase (PEPCK) related to the L-malic acid, malate dehydrogenase (MDH) and fumarase (FumC) are transformed to obtain the gene engineering bacterial strain; a deactivation mutation is carried out on the fumCto cause the interruption of a metabolic flux at the converting position from the malic acid to the fumaric acid so as to accumulate the target product L-malic acid; before the mdh, the promoter of an inner source pepck gene is added to generate the metabolic flux biased towards the malic acid; in addition, through the inducement of monofluorine sodium acetate, the activity of the PEPCK is improved, and the product feedback inhibition is greatly reduced. The bacterial strain applied to the fermentative production of the L-malic acid so as to obviously improve the yield of L-malic acid. The invention has advantages of simple technology, obvious effect and low cost and can satisfy the demand of markets.