The present invention provides for a mechanism to reduce glycerol production and increase nitrogen utilization and ethanol production of recombinant microorganisms. One aspect of this invention relates to strains of S. cerevisiae with reduced glycerol productivity that get a kinetic benefit from higher nitrogen concentration without sacrificing ethanol yield. A second aspect of the invention relates to metabolic modifications resulting in altered transport and/or intracellular metabolism of nitrogen sources present in corn mash.

The present disclosure discloses an engineering strain and application thereof in joint production of Danshensu and alanine, and belongs to the technical field of bioengineering. The present disclosure constructs a three-enzyme co-expression genetic engineering strain, and realizes joint production of Danshensu and alanine. Further, the transport of a substrate is promoted and decomposition of products is reduced by knocking out or enhancing expression of related genes on E. coli genome. The genetic engineering strain provided by the present disclosure can produce optically pure D-danshensu and L-danshensu, and jointly produce pyruvic acid. The production process is simple, raw materials are easily available, impurities are fewer, and a good industrial application prospect is achieved.

The present disclosure discloses a production method of Danshensu, belonging to the technical field of bioengineering. The present disclosure constructs a novel genetic engineering strain co-expressed by three enzymes, which can be applied to the production of optically pure 3-(3,4-dihydroxyphenyl)-2-hydroxypropionic acid. All of the (D/L)--hydroxycarboxylic acid dehydrogenase selected by the present disclosure have the characteristics of poor substrate specificity and strong optical specificity, and can produce optically pure D-danshensu and L-danshensu. Further, the production efficiency of the recombinant strain is improved by knocking out or enhancing the expression of a related gene on the E. coli genome to promote substrate transport and reduce product decomposition. The method for producing Danshensu and -ketoglutaric acid by using the transformation of the recombinant strain according to the present disclosure is simple, has easily available raw materials, few impurities, and has good industrial application prospects.

Methods for increasing carbon-based chemical product yield in an organism by genetically modifying one or more genes involved in a stringent response and/or in a regulatory network, nonnaturally occurring organisms having increased carbon-based chemical product yield, and methods for use in production of carbon-based chemical products are provided.

Application of glutamate dehydrogenase GdhA of Peptostreptococcus asaccharolyticus in increasing the yield of poly-?-glutamic acid from Bacillus licheniformis. The glutamate dehydrogenase GdhA of the Bacillus licheniformis WX-02 per se is replaced with the glutamate dehydrogenase derived from the Peptostreptococcus asaccharolyticus by means of homologous recombination, which significantly increases the level of synthesizing the poly-?-glutamic acid for the Bacillus licheniformis, and the yield of the obtained poly-?-glutamic acid from strains is increased at least by more than 20% compared with control strains.

Methods for use of a multi-arm polyethylene glycol (PEG) modifier in modification of asparaginase. The described multi-arm PEG modifier enhances the subunit interaction of a multimeric protein to maintain the multimeric protein in a polymerized form, thereby improving the stability of the multimeric protein, maintaining the bioactivity of the multimeric protein, and reducing the probability of exposure of the antigen binding site after depolymerization of the subunits, so as to reduce the immunogenicity.

The present invention concerns a method for the production of derivatives of 4-hydroxy-2-ketobutyrate chosen among 1,3-propanediol or 2,4-dihydroxybutyrate by culturing a genetically modified microorganism for the production of the desired derivative of 4-hydroxy-2-ketobutyrate, the microorganism further comprising a gene coding for a mutant glutamate dehydrogenase converting by deamination L-homoserine into 4-hydroxy-2-ketobutyrate. The invention also concerns said genetically modified microorganism.

In some embodiments, the present invention a mutated FAD-GDHa protein, wherein the mutated FAD-GDHa protein is mutated from a wild-type first species to contain at least one point mutation, wherein the mutated FAD-GDH protein comprises: P(X).sub.n=8X4(X).sub.n=16V(X).sub.n=6RN(X).sub.n=3YDXRPXCXGX.sup.3NNCMP(X).sub.n=1CP(X).sub.n=2A(X).sub.n=1Y(X).sub.n=1G(X).sub.n=6A(X).sub.n=2AG(X).sub.n=6AVV(X).sub.n=3E(X).sub.n=8-9A(X).sub.n=2Y(X).sub.n=1D(X).sub.n=5HRV(X).sub.n=5V(X).sub.n=2A(X).sub.n=3E(X).sub.n=2K(X).sub.n=4S(X).sub.n=5P(X).sub.n=1G(X).sub.n=2N(X).sub.n=4GRN(X).sub.n=1MDH(X).sub.n=4V(X).sub.n=1F(X.sub.n=6-7W(X).sub.n=1GRGP(X).sub.n=9RDGXX.sup.5R(X).sub.n=19T(X).sub.n=14L(X).sub.n=14X.sup.2(X).sub.n=1X.sup.1(X).sub.n=1E(X).sub.n=4P(X).sub.n=1NR(X).sub.n=3S(X).sub.n=4D(X).sub.n=2G(X).sub.n=7Y(X).sub.n=4Y(X).sub.n=32-35, wherein each X represents a wild-type amino acid residue of the first species and n indicates the number of the wild-type amino acid residues of the first species represented by a respective parenthetical at that position, wherein: a) X.sup.1 is selected from the group consisting of X, S, C, T, M, V, Y, N, P, L, G, Q, A, I, D, W, H, and E, wherein if X.sup.1 is L, H or V, then X.sup.2 is D; b) X.sup.3 is selected from the group consisting of G, H, D, Y, S, and X; c) X.sup.4 is selected from the group consisting of S and X; and d) X.sup.5 is selected from the group consisting of S and X.

Disclosed herein are genetically engineered hematopoietic cells, which express one or more Krebs cycle modulating polypeptides, and optionally a chimeric receptor polypeptide (e.g., an antibody-coupled T cell receptor (ACTR) polypeptide or a chimeric antigen receptor (CAR) polypeptide) capable of binding to a target antigen of interest. Also disclosed herein are uses of the engineered hematopoietic cells for inhibiting cells expressing a target antigen in a subject in need thereof.

A cofactor self-sufficient Escherichia coli and its construction method and application in the synthesis of L-glufosinate are provided. The present invention expresses a NADH kinase and key enzymes of the cofactor synthesis pathway in E. coli, and knocks out the genes of enzymes that catabolizes cofactor, and with the addition of co-metabolic intermediates during cell incubation, the intracellular NADP(H) concentration is increased by at least 50% and the catalytic activity of glufosinate dehydrogenase by 2-fold, resulting in a significant increase in the spatiotemporal yield of the glufosinate synthesis reaction.