4results about How to "Clear genetic background" patented technology

This invention discloses an intelligent programmed engineered probiotic system and its preparation method. The system uses probiotic strains as the engineered substrate bacteria, and is constructed by integrating the coding genes for superoxide dismutase (SOD), antimicrobial peptides (AMP), and a synchronized cleavage circuit (SLC) with the probiotic strains through genetic engineering technology. This invention also discloses a pH-responsive genetically engineered bacterial microsphere containing the aforementioned intelligent programmed engineered probiotic system, which is encapsulated in a carrier formed by the cross-linking reaction of sodium alginate and calcium chloride ions. The intelligent programmed engineered probiotic system and the accompanying pH-responsive genetically engineered bacterial microspheres constructed in this invention, through the synergistic design of the dual-function therapeutic modules SOD and AMP, and the programmed cleavage circuit SLC, simultaneously address the three core problems of IBD: oxidative stress, dysbiosis, and intestinal barrier damage.

This invention relates to the fields of microbial fermentation and genetic engineering technology, specifically disclosing a method for preparing human type III collagen fragments. Based on Pichia pastoris, this invention constructs a multidimensional synergistic expression system of "molecular chaperone co-expression - precursor supply - osmotic pressure adaptation regulation," reducing the structural instability of collagen fragments during secretion and post-processing, and constructing an expression system suitable for stable and efficient secretion of collagen fragments. The method described in this invention can achieve efficient extracellular secretory expression of human type III collagen fragments, and the obtained protein has high structural uniformity and stability, with a protein yield of up to 6.55 g / L under 5 L fermenter conditions. The method described in this invention is suitable for the large-scale preparation of human type III collagen fragments and provides a new technical solution for obtaining collagen products with high structural uniformity and good functional activity.

The present application relates to a kind of plasmid for endowing bacillus to degrade skatole function and its application, belong to agricultural environment microorganism and genetic engineering technical field, to solve the existing skatole management high cost, easy to produce secondary pollution, part of degradation strain exists biological safety risk, and the genetic element of natural degradation strain is difficult to cross-strain application problem.The present application discloses the plasmid of nucleotide sequence as shown in SEQ ID NO.1, by the plasmid is transformed into bacillus competent cell, is cultivated in M9 solid medium containing skatole and positive clone detection obtains recombination bacillus, it is inoculated with 0.5% to 5% inoculation amount in the medium containing 0.05 to 0.2g / L skatole, under the condition of 30 to 37 DEG C, 120 to 250rpm 4 to 48h can be degraded skatole.The present application is mainly used for the skatole deodorization of breeding manure and the like scene, provides safe controllable, efficient and scalable biological technology scheme.

This invention relates to a method and its application for enhancing the synthesis of serotonin and melatonin in *Escherichia coli*, belonging to the field of genetic engineering technology. This invention achieves the following results through the heterologous expression of high-yield serotonin and melatonin compounds Tph, Tdc, SNAT, and COMT in *Escherichia coli*, and through enzyme engineering, metabolic engineering, transport protein engineering, and reaction condition optimization: the optimized yield of serotonin synthesized from tryptophan reaches 1.92 g / L; the yield of melatonin synthesized from tryptophan reaches 3.40 g / L.