11 results about "Lysine fermentation" patented technology

The invention relates to a method for efficiently synthesizing lysine by corynebacterium glutamicum based on multi-level metabolism reconstruction, and belongs to the technical field of metabolic engineering. The method is not limited to single gene or single path transformation, but carries out system integrated regulation and control from multiple levels of lysine main synthesis pathway, central carbon metabolism redistribution, by-product synthesis inhibition and lysine transport and tolerance mechanism, and constructs a ''flux-energy-tolerance'' synergistically matched integral metabolism network; the method is a fundamental technical framework for realizing 240g / L high yield. On the premise that genetic stability of engineering bacteria and controllability of the fermentation process are guaranteed, stable and efficient synthesis of lysine under the high-density fermentation condition is achieved, the final fermentation concentration of lysine stably reaches 240 g / L or above, meanwhile, high carbon source conversion efficiency and low by-product generation level are both considered, and the method is suitable for industrial production. Therefore, the technical bottleneck that the existing lysine biological manufacturing technology is limited to the platform stage of yield of about 200 g / L for a long time is broken through.

The invention discloses a fermentation-membrane separation coupling production method of high-purity lysine, and belongs to the technical field of amino acids, the method comprises the following steps: fermentation: inoculating a corynebacterium glutamicum seed culture solution in a lysine fermentation culture medium, carrying out fermentation culture at 32-34 DEG C for 28-30 hours, and when the fermentation culture is carried out for 17-19 hours, carrying out membrane separation on the fermentation culture medium to obtain the high-purity lysine. N-(4-aminobutyl) acetamide is added; performing membrane separation: performing cross-flow filtration on the fermentation liquor by adopting a surface modified membrane, controlling the inlet pressure to be 0.4-0.5 MPa, the outlet pressure to be 0.2-0.3 MPa and the temperature to be 30-35 DEG C, and obtaining a lysine crude product after the membrane separation is finished; post-treatment: carrying out ion exchange and crystallization on the lysine crude product to obtain a high-purity lysine product; the release of viscous pollutants is reduced from a fermentation source, the pollution resistance of the membrane is improved, the flux recovery rate of the membrane is improved, and efficient coupling of fermentation and separation is realized.

The invention belongs to the technical field of biological agriculture, and particularly discloses L-lysine as well as a production method and application thereof. The method comprises the following steps: S1, carrying out aerobic fermentation on actinobacillus succinogenes, and centrifuging and filtering after fermentation to obtain sterile fermentation liquor; s2, corynebacterium glutamicum is inoculated into a fermentation culture medium for fermentation culture, after the corynebacterium glutamicum is cultured to an acid production period, microalgae active substances and the fermentation liquor obtained in the S1 are added, fermentation culture continues to be conducted for 36-48 h, and L-lysine fermentation liquor is obtained; s3, performing centrifugation, ultrafiltration and concentration on the L-lysine fermentation liquor obtained in the S2, and purifying the L-lysine through ion exchange resin to obtain the L-lysine. The invention discloses L-lysine and a production method and application thereof, the method can significantly improve the yield and purity of L-lysine, can be efficiently and stably applied to preparation of feed additives, and meets the requirements of the feed industry for high quality and safety of amino acid additives.

Disclosed is the use of a PNcgl1969(C200T) promoter and a biomaterial related thereto in the construction of a high-yield L-lysine engineered strain. The promoter is a DNA molecule obtained by means of mutating cytosine at position 200 in the PNcgl1969 promoter to thymine. By means of performing L-lysine fermentation experiments on the constructed engineered strains L-PNcgl1969 and Y-PNcgl1969 containing the PNcgl1969(C200T) promoter, it is found that a point mutation of the PNcgl1969 promoter region in Corynebacterium glutamicum is conducive to improving the yield of L-lysine. The present invention is of great significance for increasing the yield of L-lysine produced by means of bacterial fermentation.

The invention discloses a production process of L-lysine hydrochloride based on mother liquor backflow and constant flow distribution, and belongs to the technical field of biological fermentation. The process comprises the following steps: inoculating an L-lysine producing strain seed solution into a fermentation culture medium, carrying out aerobic culture, heating, and adjusting the pH value to obtain an L-lysine fermentation solution; filtering the L-lysine fermentation liquid through a ceramic membrane to obtain a clear liquid, and carrying out ion exchange to obtain an L-lysine purified clear liquid; sequentially neutralizing the L-lysine purified clear liquid with hydrochloric acid, crystallizing, concentrating and centrifuging to obtain mother liquor; finally, dividing the mother liquor into mother liquor 1 and mother liquor 2, and refluxing the mother liquor 1 to the ion exchange process to obtain the mother liquor 1 after ion exchange; and mixing the mother liquor 2 and the mother liquor 1 after ion exchange to obtain a mixed mother liquor, refluxing the mixed mother liquor to a crystallization process, and carrying out heat preservation crystallization after constant-current distribution to obtain the L-lysine hydrochloride. The crystallization stability and the production efficiency of the L-lysine hydrochloride are effectively improved through mother liquor backflow and constant flow distribution.

The present application provides a method for producing amino acid and nucleoside by microbial reinforced fermentation, which is achieved by analyzing lysine fermentation process, screening excellent fermentation strains, and adding the preferred E. coli (or adding the preferred C. glutamicum) in a timely and quantitative manner in the fermentation process based on C. glutamicum (or in the fermentation process based on E. coli), so as to obviously improve the yield and conversion rate of lysine. The present application can effectively solve the problems of unstable product quality and difficult effective control of production process in traditional lysine fermentation, and has important significance for improving fermentation efficiency and conversion rate.

The present invention relates to the technical field of microorganisms, and provides a phosphoenolpyruvate carboxykinase mutant and an application thereof in the production of lysine. Studies have found that mutating an amino acid at position 377 of phosphoenolpyruvate carboxykinase from proline to serine increases yield of lysine produced by a fermentation strain. Therefore, provided is a phosphoenolpyruvate carboxykinase mutant, wherein an amino acid sequence shown in SEQ ID NO. 7 or 9 is used as a reference sequence, and the phosphoenolpyruvate carboxykinase mutant comprises a mutation in which the amino acid at position 377 is mutated from proline to serine. The provided phosphoenolpyruvate carboxykinase mutant increases the fermentation yield of lysine and provides an effective new method for lysine production.

This invention discloses a fermentation method for L-lysine, belonging to the field of L-lysine fermentation technology. The fermentation method involves inoculating a secondary *Corynebacterium glutamicum* seed culture at an inoculation rate of 9.8-10.2% into a fermenter containing 1L of fermentation medium. The temperature inside the fermenter is maintained at 34-36℃, the pressure at 0.07-0.08 MPa, and the dissolved oxygen at 20-25%. The pH is maintained at 7-7.2 by adding ammonia. When the residual sugar decreases to 2g / L, a glucose aqueous solution is added to control the residual sugar to 5-8g / L. After 8 hours of fermentation, a betaine supplement is added. After 10 hours of fermentation, a culture medium supplement is added. This fermentation method can improve the L-lysine production rate, L-lysine yield, and sugar-acid conversion rate of *Corynebacterium glutamicum*.

Disclosed is the use of a PNcgl1855 (A244C) promoter and a biomaterial related thereto in preparation of L-lysine. The promoter is a DNA molecule obtained by mutating adenine at position 244 of a PNcgl1855 promoter into cytosine. L-lysine fermentation experiments performed on constructed engineered strains, i.e. L-PNcgl1855 and Y-PNcgl1855, containing the PNcgl1855 (A244C) promoter show that introducing a point mutation into the promoter region of the Ncgl1855 gene in Corynebacterium glutamicum contributes to an increase in the yield of L-lysine. The present invention is of great significance for increasing the yield of L-lysine in bacterial fermentation.

A continuous crystallization system suitable for lysine fermentation liquor comprises a storage tank, a first delivery pump, a first-effect falling film evaporator, a second delivery pump, a second-effect falling film evaporator, a third delivery pump, a forced circulation evaporation crystallizer, a crystal separator, a centrifugal machine and a crystal storage tank, and an air inlet of the first-effect falling film evaporator is connected with a steam delivery pipeline through a pipeline. According to the continuous crystallization system suitable for the lysine fermentation liquor, after the lysine fermentation liquor is pre-concentrated by adopting the first-effect falling film evaporator and the second-effect falling film evaporator, the lysine fermentation liquor with higher concentration is finally concentrated and crystallized by the forced circulation evaporation crystallizer, so that excessive scale deposition and excessive energy consumption can be effectively avoided; the crystallization efficiency is high, and the product granularity is uniform; the centrifugal machine is adopted to separate liquid in crystals, the product purity is improved, the separated liquid is conveyed to the forced circulation evaporation crystallizer again to be treated, and the product yield of the lysine fermentation liquor is improved.

The present application relates to the field of microbial technology, and specifically discloses a recombinant microorganism and application of reducing expression amount of aromatic amino acid transporter in fermentation production. The present application finds that inactivation of aromatic amino acid transporter aroP can improve the production efficiency of lysine. Further, a recombinant microorganism is provided, wherein the expression amount of aromatic amino acid transporter aroP is reduced compared with a starting strain; the starting strain is corynebacterium. The present application provides a new and effective way for lysine fermentation production.