37results about How to "Good passage stability" patented technology

The invention discloses streptomyces albidoflavus and application thereof in production of epsilon polylysine, and belongs to the field of microbial fermentation engineering. The Streptomyces albus GS114 provided by the invention can grow on an agar culture medium containing more than 10 [mu] g / ml of one or more of streptomycin, gentamycin and rifamycin, shows very strong antibiotic resistance, can normally grow in a liquid culture medium with a pH value of 2.5-3.0 and can synthesize a large amount of epsilon PL, and after fermentation for 200 h, the Streptomyces albus GS114 can be used as anantibiotic. The concentration of epsilon polylysine in the fermentation liquor is 65.7 g / L, and the yield of epsilon polylysine reaches 80.0 g / L or above after fermentation is conducted for 240 h. Thestrain also has good passage stability, and is an epsilon PL industrial production strain with great potential.

The invention provides a method for rapid preparation of epidemic and infectious bronchitis vaccine. The method takes infectious clone of an infectious bronchitis virus H120 vaccine strain as a skeleton carrier, then replaces an antigen gene in the skeleton carrier with a targeted antigen gene of an infectious bronchitis epidemic virus strain, so as to obtain the method of recombining bronchitis virus, and the targeted antigen gene is prepared from S gene fragments of infectious bronchitis epidemic strains with different serotypes / genotypes in an gomphosis mode; replacement can also be the simultaneous replacement of the targeted antigen gene and a N gene, and a signal peptide region of an original S1 gene in the skeleton carrier needs to be preserved during the replacement. The method forthe rapid preparation of the epidemic and infectious bronchitis vaccine has the beneficial effects that an operation method is simple and easy to conduct, therepeatability is high, the generation stability is good, the frequent variation of IBV epidemic can be quickly and efficiently tackled, and the method provides a new idea for the construction of a carrier vaccine.

The invention discloses a strain for highly yielding enramycin, simultaneously provides a screening method of the strain, and provides application of the strain in enramycin production. The preserving number of the strain DCS067 for highly yielding enramycin is CGMCCONO: 6220, the preserving unit is China General Microbiological Culture Collection Center (CGMCC), and the preserving date is June 14, 2012. The DCS067 strain enables production rate of enramycin to be improved by 47.80%.

The invention discloses a strain of streptomyces producing ε-polylysine and its application, belonging to the technical field of bioengineering. The Streptomyces albulus strain (Streptomyces albulus) M-Z18 of the present invention has been deposited in the China General Microorganism Collection and Management Center on July 29, 2019, and the preservation number is CGMCC NO: M 2019589. The Streptomyces albicans M-Z18 strain of the present invention can grow rapidly on a medium with succinic acid as a carbon source, and has the ability to efficiently synthesize ε-polylysine with sulfaguanidine resistance. The strain of the present invention carries out fed-batch fermentation under the pH shock strategy, the cumulative concentration of ε-polylysine can reach 54.7g / L, and the production efficiency can reach 6.83g / L / d, which is a strain of ε-polylysine with great potential Polylysine industrial production strain.

The invention provides a streptomyces fungicidious mutant strain DC461, wherein the collection number is CGMCC (China General Microbiological Culture Collection Center) No. 5811, the collection unit is China Committee for Culture Collection of Microorganisms, and the collection date is February 27, 2012. The invention further provides a preparation method of the strain and application of the strain in terramycin production. The mutant strain DC461 provided by the invention is bearable to a high-concentration defoamer and can be used for increasing the production level of terramycin.

The invention discloses a high-yield penicillin strain, and provides a screening method for the above-mentioned strain and the application of the above-mentioned strain in the production of penicillin, belonging to the technical field of antibiotic production and its application. The bacterial strain of the present invention increases the fermentation unit of penicillin by 13.2%, effectively improves the output of penicillin and reduces production cost, and its screening method comprises the following steps: (A) protoplast preparation; (B) high-energy electron mutagenesis; (C) ) rationalization screening; (D) shake flask screening. The invention provides a screening method for penicillin with strong purpose and high probability of mutant strains and its application.

The invention provides a production strain of L-homoserine, which is characterized in that: it has a single stable chromosome, does not contain plasmid form or other free DNA carriers, and one or more of its chromosomal DNA is related to the synthesis of L-threonine The genes of the patients are knocked out or weakened, and / or mutated to enhance, and / or one or more genes related to the L-homoserine metabolic pathway are integrated on their chromosomal DNA.

The invention discloses a recombinant plasmid for genetic transformation of pleurotus eryngii and application thereof and provides a DNA (Deoxyribonucleic Acid) segment and the recombinant plasmid containing the DNA segment, wherein the DNA segment sequentially comprises a promotor shown as a sequence 1 and a terminator shown as a sequence 2 from upstream to downstream. According to a method for genetic transformation of the pleurotus eryngii, which is established by the invention, the foundation for theoretical basis and technical support for fundamental research and molecular breeding of the growth and development mechanism of the pleurotus eryngii is laid, the storage for developing a novel bioreactor is provided and wide application field for developing and utilizing pleurotus eryngiiresources and bioactive substances thereof is opened up.

The invention discloses a method for simultaneously preparing two kinds of monoclonal antibodies. In the method, the conjugate of 33F type pneumonia polysaccharide and hepatitis B surface protein is used as an antigen to immunize mice, and mouse splenocytes with higher antibody levels after immunization are selected. Fusion with SP2 / 0 myeloma cells, and then specific screening by 33F pneumonia polysaccharide, hepatitis B surface protein, and 33F pneumonia polysaccharide and hepatitis B surface protein conjugates as antigens to obtain hybridoma cells, and at the same time prepare a specific recognition of 33F pneumonia Monoclonal antibodies to polysaccharide and hepatitis B surface protein. The method of the present invention to simultaneously prepare monoclonal cell line cells and specific monoclonal antibodies for polysaccharides and proteins after immunization with pneumonia conjugates using hepatitis B surface protein as a carrier saves workload and improves screening efficiency. At the same time, the present invention The two monoclonal antibodies provided have the advantages of high specificity, high sensitivity and good passage stability.

The invention provides a Vero cell line capable of stably expressing protein P54 of an African swine fever virus. The collection number of the cell line is CGMCC No.14316. The cell line not only can identify a polyclonal antibody of African swine fever, but also can generate specific reaction with positive serum of an African swine fever-infected pig. The monoclonal Vero cell line of an African swine fever P4 antigen can be used for stably expressing the protein P54 of the African swine fever virus, and can be used as a cell model or a virus infection model; the cell transmission stability ishigh, the growing speed is high, and culture conditions are simple; a large number of cell lines can be provided; the cell line has a good application prospect for researches on detection and pathogenesis mechanisms of the African swine fever.