33results about How to "Improve substrate utilization" patented technology

The invention relates to compositions and methods utilizing split polymerase enzymes composed of at least two discrete polypeptides that stably associate to form a single polymerase. The invention further relates to nucleic acid constructs for expressing the split polymerases of the invention, and methods for using the split polymerases of the invention. The enzymes of the invention are useful in many applications calling for the detectable labeling of nucleic acids and are particularly useful in quantitative PCR (QPCR) and DNA sequencing applications.

The invention discloses a Sclerotinum and a method for fermenting and producing scleroglucan, belonging to the technical field of microbes. The strain CCTCC NO:M2017646 provided by the present invention can be fermented for 56 hours under the condition of glucose carbon source concentration of 75g / L to reach the effect of scleroglucan production of nearly 20g / L, which is obviously better than the current international scleroglucan production of 150g / L. Under the culture condition of L sucrose, the yield of 72h is 26g / L, the substrate utilization rate is increased by 58%, and the cost is significantly reduced. The method is superior to the existing dextran production process and has important industrial application prospects.

The invention belongs to the technical field of bioengineering and relates to a method for reducing decomposition of cephalosporin C (CPC). The method comprises the following steps: knocking out beta-lactamase genes and acetyl esterase genes of host bacteria by using a Red recombinant system; transforming cephalosporin C acylase genes into the host bacteria; expressing the cephalosporin C acylaseby using the host bacteria; preparing cephalosporin C acylase crude enzyme solution or immobilized cephalosporin C acylase crude enzyme; and adding the cephalosporin C acylase crude enzyme solution or immobilized cephalosporin C acylase crude enzyme into cephalosporin C substrate working liquid and catalyzing to generate 7-aminocephalosporin acid (ACA). CPC acylase is prepared by the method. In the process of catalyzing the CPC to generate 7-ACA by using the harvested crude enzyme, the utilization ratio of the CPC is increased to over 98 percent.

The invention provides recombinant bacteria capable of synthesizing 3-hydracrylic acid by using glucan as well as a construction method and application of the recombinant bacteria, and belongs to the field of gene engineering and fermentation engineering. Klebsiella pneumoniae is host bacteria for expressing a gene lgk capable of encoding levodextran kinase and a gene aldH capable of encoding aldehyde dehydrogenase. The construction method comprises the following steps: obtaining a recombinant carrier puC18-lgk-aldH, converting the recombinant carrier puC18-lgk-aldH into a competent cell of the host Klebsiella pneumoniae, and obtaining the recombinant bacteria. By use of the levodextran kinase gene lgk and the aldehyde dehydrogenase gene aldH which are optimized through a codon, in combination with the whole scheme, the substrate use rate is increased, and the yield is increased.

The invention discloses a method for co-producing chiral hydroxyl esters of uridine phosphoryl compounds. The method uses orotic acid and β-keto ester compounds as substrates, uses glucose as an energy donor, and utilizes permeable Simultaneous production of uridine phosphoryl compounds and chiral hydroxyl esters by yeast cells. The present invention utilizes the principles of whole-cell catalysis and metabolic engineering, establishes a metabolic network model and analyzes metabolic flow, and utilizes permeable yeast cells to co-produce uridine phosphoryl compounds and chiral hydroxyl esters, increasing the yield and reducing production costs , The synthesis time is shortened, and the utilization rate of the substrate is greatly improved.

The present invention relates to a method for separating acetic acid in fermentation liquid for biohydrogen production by bipolar membrane electrodialysis technique. The invention solves the problem that the prior method for separating acetic acid has complex technology, low current efficiency, large energy consumption and long operation time. The method comprises a first step of circularly pumping the pre-treated fermentation liquid for biohydrogen production into a separation chamber of a bipolar membrane electrodialyzer; a second step of circularly pumping pure water or acetic acid solution into an enriched chamber of the bipolar membrane electrodialyzer; and a third step of circularly pumping Na2SO4 electrolyte with the mass concentration of 5% into an anode chamber and a cathode chamber, and performing bipolar membrane electrodialysis so as to accomplish the separation of acetic acid in fermentation liquid for biohydrogen production. The operation time in the invention is decreased by more than 80%, the technology is simple, a separation system is of closed cycling, no pollutant is discharged, and the method is green and environment-friendly. The removal rate of acetic acid in the invention is more than 85%, the recovery rate of acetic acid is more than 85-95%, the current efficiency is up to 60-70%, and the energy consumption is reduced.

A method for biogas slurry advanced treatment and biogas upgrading to prepare methane based on microbial electrocatalysis. The biogas slurry is used to start the microbial electrochemical system, and the volatile fatty acids and refractory organic compounds in the biogas slurry are degraded under the action of anode electroactive microorganisms. And cooperating with sulfur-oxidizing microorganisms to oxidize hydrogen sulfide in raw biogas to polysulfides, while polysulfides act as redox shuttles to transfer electrons and protons generated at the anode to the cathode, and reduce them in the crude biogas under the action of methanogenic microorganisms at the cathode The carbon dioxide is methane, which realizes the simultaneous completion of advanced treatment of high-concentration biogas slurry, desulfurization and decarbonization of biogas.