Abstract: The present disclosure discloses a genetically engineered strain, belonging to the technical field of bioengineering. L-amino acid oxidase genes, ?-keto acid decarboxylase genes, alcohol dehydrogenase genes, and enzyme genes capable of reducing NAD(P) to NAD(P)H are introduced into the genetically engineered strain of the present disclosure. The present disclosure further discloses a construction method and application of a recombinant Escherichia coli genetically engineered strain. When being applied to the biosynthesis of phenylethanoids, the method of the present disclosure has the characteristics of simple operation, low cost, and high synthesis efficiency and optical purity of the product, and has good industrialization prospects.

Abstract: In some aspects, the present disclosure provides a dual emissive pH response noble metal nanoparticle which produces a ratiometric fluorescence signal based upon changes in the pH. In another aspect, the noble metal nanoparticle may be used in bioimaging applications as well as to detect in vivo changes of pH.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: The present disclosure discloses a genetically engineered strain, belonging to the technical field of bioengineering. L-amino acid oxidase genes, ?-keto acid decarboxylase genes, alcohol dehydrogenase genes, and enzyme genes capable of reducing NAD(P) to NAD(P)H are introduced into the genetically engineered strain of the present disclosure. The present disclosure further discloses a construction method and application of a recombinant Escherichia coli genetically engineered strain. When being applied to the biosynthesis of phenylethanoids, the method of the present disclosure has the characteristics of simple operation, low cost, and high synthesis efficiency and optical purity of the product, and has good industrialization prospects.

Abstract: An embodiment of the invention is directed to a composition comprising a noble metal nanoparticle, wherein the surface of the noble metal nanoparticle is coated with polyethylene glycol (PEG) having a size of 0.35 kDa to 5 kDa, and wherein the noble metal nanoparticle is about 2 nm to 10 nm in hydrodynamic diameter. In an embodiment of the invention, a therapeutic agent is also present on or in said nanoparticle.

Abstract: In some aspects, the present disclosure provides a dual emissive pH response noble metal nanoparticle which produces a ratiometric fluorescence signal based upon changes in the pH. In another aspect, the noble metal nanoparticle may be used in bioimaging applications as well as to detect in vivo changes of pH.