Methods and materials related to producing aspartic acid, β-alanine and salts of each thereof are disclosed. Specifically, isolated nucleic acids, polypeptides, host cells, methods and materials for producing aspartic acid by direct fermentation from sugars are disclosed.

Methods and materials related to producing aspartic acid, β-alanine and salts of each thereof are disclosed. Specifically, isolated nucleic acids, polypeptides, host cells, methods and materials for producing aspartic acid by direct fermentation from sugars are disclosed.

The disclosure discloses an L-aspartate α-decarboxylase mutant and application thereof, and belongs to the technical field of enzyme engineering. In the disclosure, lysine at position 221 of L-aspartate α-decarboxylase is mutated to arginine, glycine at position 369 is mutated to alanine, and the obtained new mutant enzymes have better temperature tolerance and are beneficial to industrial production. The K221R and G369A recombinant strains are subjected to high-density fermentation, and with sodium L-aspartate as a substrate, a whole cell catalytic reaction is carried out to prepare β-alanine. Compared with a chemical production method, the method has the advantages that the production process is safe and clean, and has no environmental pollution. Compared with a pure enzyme catalysis method, the method has the advantages that the operation is simple and convenient. The yield of the final product β-alanine reaches 91% and 90% respectively, and the concentration reaches 162.15 g/L and 160.42 g/L respectively.

The disclosure discloses an L-aspartate α-decarboxylase mutant and application thereof, and belongs to the technical field of enzyme engineering. In the disclosure, lysine at position 221 of L-aspartate α-decarboxylase is mutated to arginine, glycine at position 369 is mutated to alanine, and the obtained new mutant enzymes have better temperature tolerance and are beneficial to industrial production. The K221R and G369A recombinant strains are subjected to high-density fermentation, and with sodium L-aspartate as a substrate, a whole cell catalytic reaction is carried out to prepare β-alanine. Compared with a chemical production method, the method has the advantages that the production process is safe and clean, and has no environmental pollution. Compared with a pure enzyme catalysis method, the method has the advantages that the operation is simple and convenient. The yield of the final product β-alanine reaches 91% and 90% respectively, and the concentration reaches 162.15 g/L and 160.42 g/L respectively.

Disclosed is a recombinant microorganism capable of growing using only carbon dioxide and formic acid by introducing and improving a metabolic pathway for synthesizing pyruvic acid from carbon dioxide and formic acid to enhance pyruvic acid synthesis efficiency and performing additional genetic manipulation, and a method for producing useful substances using the same. Advantageously, the recombinant microorganism is capable of synthesizing pyruvic acid, a C3 organic compound, at a remarkably improved rate, and in particular, grows well even in a medium containing only carbon dioxide and formic acid as carbon sources without a glucose supply, and is thereby capable of synthesizing pyruvic acid and various high value-added compounds using the same as an intermediate product in an economically efficient manner.

Disclosed is a recombinant microorganism capable of growing using only carbon dioxide and formic acid by introducing and improving a metabolic pathway for synthesizing pyruvic acid from carbon dioxide and formic acid to enhance pyruvic acid synthesis efficiency and performing additional genetic manipulation, and a method for producing useful substances using the same. Advantageously, the recombinant microorganism is capable of synthesizing pyruvic acid, a C3 organic compound, at a remarkably improved rate, and in particular, grows well even in a medium containing only carbon dioxide and formic acid as carbon sources without a glucose supply, and is thereby capable of synthesizing pyruvic acid and various high value-added compounds using the same as an intermediate product in an economically efficient manner.

The present disclosure relates to a modified polypeptide with attenuated activity of citrate synthase and a method for producing an aspartate-derived L-amino acid using the modified polypeptide.

The present disclosure relates to a modified polypeptide with attenuated activity of citrate synthase and a method for producing an aspartate-derived L-amino acid using the modified polypeptide.

An ultrasonic-assisted method for preparing phosphatidylserine, comprising the following steps: adding 100-130 parts of phospholipid into a mixture of 150-200 parts of L-serine, 10-20 parts of anhydrous calcium chloride and 400-500 parts of pure water, adding 20-25 parts of phospholipase D for enzymatic hydrolysis reaction, and applying ultrasound in the enzymatic hydrolysis reaction for treatment. The present invention uses an ultrasonic treatment technology to assist phospholipase D to act on phosphatidylcholine and serine to undergo an enzymatic hydrolysis reaction to prepare phosphatidylserine, and at the same time, the ultrasonic frequency, ultrasonic intensity, ultrasonic power, ultrasonic time, ultrasonic temperature, enzyme activity and other parameters are controlled synergistically, so that the enzymatic hydrolysis conversion rate is 98% or higher.

An ultrasonic-assisted method for preparing phosphatidylserine, comprising the following steps: adding 100-130 parts of phospholipid into a mixture of 150-200 parts of L-serine, 10-20 parts of anhydrous calcium chloride and 400-500 parts of pure water, adding 20-25 parts of phospholipase D for enzymatic hydrolysis reaction, and applying ultrasound in the enzymatic hydrolysis reaction for treatment. The present invention uses an ultrasonic treatment technology to assist phospholipase D to act on phosphatidylcholine and serine to undergo an enzymatic hydrolysis reaction to prepare phosphatidylserine, and at the same time, the ultrasonic frequency, ultrasonic intensity, ultrasonic power, ultrasonic time, ultrasonic temperature, enzyme activity and other parameters are controlled synergistically, so that the enzymatic hydrolysis conversion rate is 98% or higher.