CN-120818577-B - Polymeric glutamate sugar ester and biological fermentation preparation method and application thereof

Abstract

The application relates to a polymeric glutamate sugar ester and a biological fermentation preparation method and application thereof, belonging to the technical field of biological fermentation. According to the scheme, amino acid and functional oligosaccharide are used as substrates, and the high-efficiency directional assembly of the high-molecular polymer glutamate sugar ester is realized by designing an integrated cell factory biosynthesis technology. The application provides a brand new compound of poly (glutamic acid) sugar ester, and provides a biological fermentation method of the poly (glutamic acid) sugar ester, which is suitable for industrial continuous production, and the prepared poly (glutamic acid) sugar ester has narrower molecular weight distribution and better product uniformity.

Inventors

• SONG HAIMEI
• DIAO HONGXIA
• TAI WENJING
• ZHANG CHAOYI
• WANG MENGJIAO
• WANG CHENGCHENG
• WANG YINGYING
• ZHAO MINGMING

Assignees

• 青岛海大生物集团股份有限公司

Dates

Publication Date

20260512

Application Date

20250918

Claims (3)

1. 1. The biological fermentation preparation method of the polymerized glutamic acid sugar ester is characterized by comprising the step of utilizing engineering bacteria to carry out biological fermentation by taking glutamic acid or salt thereof and rhamnose as substrates; And controlling the engineering bacteria to express pgsB, pgsC and pgsA firstly and synthesize polyglutamic acid or salt thereof by glutamic acid or salt thereof, and controlling the engineering bacteria to express acyl transferase RhlA and glycosyltransferase RhlB from Pseudomonas aeruginosa and synthesize the polyglutamic acid sugar ester by polyglutamic acid or salt thereof and rhamnosaccharide.
2. 2. The method for biologically fermenting and preparing the polyglutamate according to claim 1, wherein the acylase and the glycosyltransferase share one promoter, and a linker is included between the acylase and the glycosyltransferase.
3. 3. The biological fermentation preparation method of the polyglutamic acid sugar ester is characterized by comprising the step of utilizing engineering bacteria to carry out biological fermentation by taking polyglutamic acid or salt thereof and rhamnose oligosaccharide as substrates; the engineering bacteria express an acyl transferase RhlA and a glycosyltransferase RhlB from Pseudomonas aeruginosa.

Description

Polymeric glutamate sugar ester and biological fermentation preparation method and application thereof Technical Field The application relates to a polymeric glutamate sugar ester and a biological fermentation preparation method and application thereof, belonging to the technical field of biological fermentation. Background Polyglutamic acid (gamma-PGA) is a natural anionic high molecular polymer polymerized from glutamic acid monomers through gamma-amide bonds, and has excellent biodegradability, biocompatibility and super-strong water-retaining and moisture-retaining capabilities. In the agricultural field, the gamma-PGA shows excellent fertilizer synergism, soil improvement and stress resistance and growth promotion functions due to the unique molecular structure. The molecular chain of the gamma-PGA can chelate the medium and trace elements such as calcium and magnesium in soil, prevent fertilizer solidification and improve fertilizer utilization rate, has strong water holding capacity, can effectively inhibit soil water evaporation, plays a role in drought resistance and soil moisture conservation, and meanwhile, the gamma-PGA can promote root system development of crops and enhance the resistance of crops to abiotic stress such as drought, saline alkali and the like. Seaweed, particularly green and brown seaweed, is rich in a variety of biologically active polysaccharides and oligosaccharides. For example, rhamno sulfate (ROS) derived from green algae and Algin Oligosaccharide (AOS) derived from brown algae have been demonstrated to have various biological activities such as promotion of plant growth, promotion of plant immune response, enhancement of plant stress resistance, and improvement of crop quality. The trehalose is used as a signal molecule, can regulate the expression of related genes in plants, induces the plants to generate disease resistance, and can be used as natural organic nutrients. The ester-linked bioactive molecules play an important role in plant growth regulation. Well-known brassinolide (a sterol ester) is one of the most active and widely applied plant growth regulators at present, and can remarkably enhance photosynthesis of crops, increase yield and stress resistance. Similarly, diethyl aminoethyl hexanoate (DA-6) is also highly active as a carboxylate for plant growth regulation. In addition, sugar ester biosurfactants such as rhamnolipid are also found to have a growth promoting effect on plants. These studies show that the active groups are connected through ester bonds, so that a synergistic effect is generated, and meanwhile, even a brand new function can be endowed to the molecule, and the structural characteristics determine the functional diversity. The traditional preparation of polyamino acid and saccharides by esterification adopts a chemical catalytic esterification method, and has the defects that 1) byproducts are more (for example, sulfonation byproducts of concentrated sulfuric acid catalytic reaction are more than or equal to 15 percent), the purity of target products is low (85 percent), 2) the reaction energy consumption is high (high temperature is more than 80 ℃ or high pressure condition is needed), 3) the molecular weight distribution of the products is difficult to control (polydisperse coefficient PDI is more than 1.5), and 4) the post treatment is complex due to chemical catalyst residues. Therefore, it is necessary to provide a preparation process which can overcome the defects of the conventional chemical catalytic esterification process, and simultaneously, the molecular weight distribution of the product is narrower, and the uniformity of the product is better. It should be noted that the above background art is only for illustrating the technical route of the present application and does not necessarily constitute prior art. Disclosure of Invention In order to solve the problems, the application provides a polymeric glutamate sugar ester, a biological fermentation preparation method and application thereof, and in particular provides a high-efficiency preparation method of the polymeric glutamate sugar ester based on an enzyme catalysis self-assembly technology, by adopting an integrated cell factory biological synthesis technology, realizes the accurate assembly of glutamic acid and functional oligosaccharide under mild conditions (below 45 ℃ and pH of 5.0-7.0), reduces the cost by 50-60% compared with a chemical catalytic esterification method, and the prepared polymer glutamate has narrower molecular weight distribution and better product uniformity. According to the application, the structures of the polyglutamic acid and the functional oligosaccharide are fused, the carboxyl of the glutamic acid and the hydroxyl of the functional oligosaccharide directionally react to form an ester bond, and then the novel multi-effect biopolymer with a reticular macromolecular structure is formed through intermolecular polymerization and crosslinking, so