183 results about "Wild strain" patented technology

The invention relates to the technical field of a preparation method of a type A recombinant botulinum toxin, in particular to a type A botulinum toxin obtained by adopting a gene recombination technology, and the amino acid sequence of the type A botulinum toxin is consistent with the sequence of the type A botulinum toxin prepared by extracting and purifying a wild strain Clostridium botulinum. According to the technical scheme, the single-chain protein of the botulinum toxin A sequentially comprises a botulinum toxin A light chain or a modified botulinum toxin A light chain, a connecting region and a botulinum toxin A heavy chain. According to the scheme, the high-quality recombinant botulinum toxin A is obtained after the single-chain protein is subjected to fermentation, crude purification, enzyme digestion and fine purification. According to the technical scheme, the problems of complex process, long period, high safety risk and the like in the existing process for preparing the botulinum toxin A from the wild bacterial strain clostridium botulinum can be solved, and meanwhile, the problem that the amino acid sequence consistent with that of the botulinum toxin A prepared from the wild bacterial strain clostridium botulinum cannot be obtained through the existing gene recombination technology is solved.

The invention discloses a kitchen waste oil-based sophorolipid high-yield candida utilis strain and an application thereof. Belongs to the technical field of directional domestication breeding. According to the method, wild candida bombicola is used as an original strain, and is sequentially domesticated in a culture medium containing kitchen waste oil with the concentration gradient of 2%, 4%, 6%, 8% and 10% to obtain the S.bombicola x10. The invention further discloses an application of the domesticated strain in fermentation production of sophorolipid, after the strain is subjected to shake flask fermentation, the sophorolipid yield reaches 60.19 g / L and is improved by 16.22% compared with that of a wild strain, and the acid type sophorolipid yield is improved by 32.11%. When the concentration of the lactone sophorolipid generated by fermentation is 1.25 mg / mL, the growth of the bacillus subtilis is completely inhibited. The invention provides an excellent production strain for industrial production of sophorolipid, and has good theoretical research significance and practical application value.

The invention relates to the technical field of biology, and aims to provide a monoclonal antibody 7A12 for identifying gene type 2 swine fever as well as a preparation method and an application method of the monoclonal antibody 7A12. The monoclonal antibody comprises Ig structural domains VH CDR1, VH CDR2 and VH CDR3 of a heavy chain of the antibody, and Ig structural domains VL CDR1, VL CDR2 and VL CDR3 of a light chain of the antibody, wherein the amino acid sequences of the VH CDR1, the VH CDR2 and the VH CDR3 are respectively as shown in SEQ ID NO: 1 to SEQ ID NO: 3; the amino acid sequences of the VL CDR1, the VL CDR2 and the VL CDR3 are respectively as shown in SEQ ID NO: 4 to SEQ ID NO: 6. The antibody provided by the invention has the advantages of high titer, strong specificity, high affinity and the like; the kit has the advantages of high sensitivity and strong specificity, has no cross reaction with the type 1 swine fever vaccine strain, and can identify and diagnose swine fever gene type 2 wild strain infection and vaccine immunity in serology; the method can be further used for establishing a blocking ELISA kit for identifying the gene type 2 hog cholera, and can effectively diagnose and purify the gene type 2 hog cholera virus.

The invention relates to a PCR (Polymerase Chain Reaction) kit and method for identifying brucella pathogens and application. The PCR kit comprises primer pairs and probes for simultaneously detecting brucella BA0711 vaccine strains, M5-9026 vaccine strains, Rev.1 vaccine strains and wild strains. A primer pair for detecting the brucella BA0711 vaccine strain is shown as SEQ ID NO.1-2, and a probe is shown as SEQ ID NO.3; a primer pair for detecting the M5-9026 vaccine strain is shown as SEQ ID NO.4-5, and a probe is shown as SEQ ID NO.6; a primer pair for detecting the Rev.1 vaccine strain is shown as SEQ ID NO.7-8, and a probe is shown as SEQ ID NO.9; a primer pair for detecting positive brucella is shown as SEQ ID NO.10-11, and a probe is shown as SEQ ID NO.12; the kit has the advantages of high sensitivity and strong specificity, and can simultaneously distinguish a plurality of vaccine strains and wild strains.

The invention discloses a streptococcus suis type 2 gene deletion strain as well as a construction method and application thereof, and belongs to the technical field of biological products. According to the invention, the B9H0105210 gene in the genome of the streptococcus suis serotype 2 SC19 is deleted in a homologous recombination manner for the first time, the hydrogen peroxide and nitric oxide stress resistance of the constructed streptococcus suis serotype 2 gene deleted strain is reduced, and the pathogenicity to mice is obviously weakened; moreover, the growth performance of the streptococcus suis type 2 gene-deleted strain is not greatly different from that of a wild strain SC19, the condition of gene recovery does not exist after continuous passage, and the streptococcus suis type 2 gene-deleted strain has an application prospect as an attenuated live vaccine, has a good immune protection effect on different genotypes of streptococcus suis such as the streptococcus suis type 2 strain SC19 and streptococcus suis type 2 P1 / 7, and has a good application prospect. And a certain cross immune protection performance is achieved.

The invention discloses an E3 ubiquitin ligase gene ulA, the nucleotide sequence of which is shown as SEQ ID NO: 1. The gene is knocked out from fusarium oxysporum by using a homologous recombination method to obtain a mutant strain ulA; compared with a wild strain, the mutant hulA has the advantages that the spore yield is reduced, the spore germination is delayed, the response capability to various abiotic stresses is reduced, the pathogenicity to panax notoginseng plants is reduced, and the sensitivity to six bactericides is increased, and experimental results show that the gene plays an important role in pathogenicity, drug resistance and the like of fusarium oxysporum. The gene can be used as a target gene for developing an anti-fusarium oxysporum preparation.

The invention discloses a mint McTTG2 gene as well as an expression protein and application thereof, and relates to the technical field of plant genetic engineering. The nucleotide sequence of the mint McTTG2 gene disclosed by the invention is shown as SEQ ID NO. 1, and the amino acid sequence of the expression protein of the mint McTTG2 gene is shown as SEQ ID NO. 2. The method comprises the following steps: constructing an expression vector of a mint McTTG2 gene, and transforming the expression vector into an arabidopsis thaliana mutant; and cultivating and screening to obtain a transgenic arabidopsis thaliana plant of which the procyanidine content is obviously increased. A transgenic experiment shows that after the McTTG2 gene is over-expressed in the mutant ttg2-7, the content of procyanidine is remarkably increased; compared with the mutant ttg2-7, the number of epidermal hairs on leaves of ttg2-7 / 35S:: McTTG2-1 and-2 strains is obviously increased, which is close to that of wild strains. Gene resources are provided for plant variety improvement, and cultivation of new mint varieties is facilitated.

The invention relates to the technical field of carotenoid cleavage dioxygenase, and discloses a carotenoid cleavage dioxygenase mutant and application thereof. In order to improve the efficiency of converting carotenoid in tobacco into aroma molecule beta-ionone, specific mutation of characteristic sites is carried out on carotenoid cleavage dioxygenase (PhCCD1) from petunia, that is, serine (S) at the 428 site of the carotenoid cleavage dioxygenase is mutated into cysteine (C) or tyrosine (Y) to obtain a mutant S428C or S428Y, and the mutant S428C or S428Y is converted into beta-ionone. The yield of the beta-ionone converted from the carotenoid is greatly improved. Experiments prove that the yields of beta-ionone of S428C and S428Y respectively reach 54.2 mg / L and 50.6 mg / L, which are respectively increased by 69.7% and 58.5% compared with those of a wild strain WT.

The invention belongs to the technical field of microorganisms, and particularly relates to stenotrophomonas maltophilia yg3 and application thereof. The invention discloses stenotrophomonas maltophilia yg3, and the preservation number of the stenotrophomonas maltophilia yg3 is CGMCC (China General Microbiological Culture Collection Center) No.34131. The stenotrophomonas maltophilia yg3 disclosed by the invention has the capability of efficiently synthesizing indoleacetic acid (IAA), and the IAA yield of 98.10 mg / L can be realized without optimization in an NB culture medium containing 5mM L-tryptophan, which is obviously higher than that of other wild strains. Moreover, the stenotrophomonas maltophilia yg3 has a remarkable growth promoting effect on plants (such as hot peppers), pot experiments show that the stenotrophomonas maltophilia yg3 can remarkably increase the number of effective leaves, the plant height and the biomass of the hot peppers, and the stenotrophomonas maltophilia yg3 can be applied to the field of microorganisms. Particularly, the method has important application value in the fields of microbial plant growth promoters and green synthesis of IAA (indoleacetic acid).

The invention relates to the technical field of molecular biological detection, and particularly discloses a quadruple fluorescent PCR primer probe combination, a reaction system and a detection method for identifying a mycoplasma gallisepticum wild strain and a vaccine strain. The quadruple fluorescent PCR primer probe combination for identifying the mycoplasma gallisepticum wild strain and the vaccine strain comprises a universal primer probe group for detecting mycoplasma gallisepticum and a specific primer probe group specially aiming at three vaccine strains F-36, TS-11 and 6 / 85 respectively. According to the quadruple fluorescent PCR primer probe combination, the reaction system and the method for identifying the mycoplasma gallisepticum wild strain and the vaccine strain, the purpose of simultaneously detecting and distinguishing DNA of the mycoplasma gallisepticum wild strain and DNA of three different vaccine strains (F-36, TS-11 and 6 / 85) of the mycoplasma gallisepticum wild strain can be achieved, so that detection and differential diagnosis are more efficient, economical, simple and convenient; the kit has the advantages of high sensitivity, good specificity, rapidness, high flux, simplicity and convenience in operation and the like.

The invention discloses engineering chlamydomonas reinhardtii for synthesizing high-value pigment and a construction method and application thereof.An engineering chlamydomonas reinhardtii strain Blup-BKT-CHYB-CHLC is preserved in the China General Microbiological Culture Collection Center on September 1, 2025, and the preservation number is CGMCC NO.46634. The content of astaxanthin in the constructed engineering chlamydomonas reinhardtii strain reaches 25.5 mg / L, and the content of astaxanthin in the engineering chlamydomonas reinhardtii strain reaches 9.5 mg / L; in addition, the light energy utilization efficiency is remarkably enhanced, the stress resistance is improved, very strong oxidation resistance is achieved, the accumulation of astaxanthin endows the engineering strain with highlight tolerance, the yield of high-value pigments is increased, and the biomass of the engineering strain is greatly superior to that of a wild strain under the highlight condition. In addition, the chlorophyll c synthase is applied to the reconstruction of a pigment system of the chlamydomonas reinhardtii for the first time, a frontier tool is quickly converted, and a molecular mechanism of'chlorophyll c-astaxanthin-blue pigment 'for synergistically regulating the photosynthetic efficiency of the chlamydomonas reinhardtii and product synthesis is clarified for the first time. The research blank of pigment system coupling regulation and control of photosynthesis and metabolism in the chlamydomonas reinhardtii is filled.

The invention provides a classical swine fever virus subunit vaccine and a preparation method thereof, the classical swine fever virus subunit vaccine is based on an E2 protein gene and a GP67 signal peptide gene of a CSFV 1.1 strain, a recombinant expression vector is constructed through gene cloning, a classical swine fever virus E2 recombinant protein is obtained through expression of an insect baculovirus system, and the classical swine fever virus subunit vaccine is obtained. And the recombinant protein is combined with a colloidal manganese adjuvant to prepare the swine fever virus subunit vaccine. The hog cholera virus E2 recombinant protein is close to natural E2 protein in structural function, high in reduction degree, high in expression quantity and suitable for vaccine production and application; the vaccine can generate specific humoral immunity and relatively strong cellular immunity, and is beneficial to removal of CSFV in an animal body; meanwhile, the vaccine can be distinguished from attenuated vaccine strain immunization or wild strain infection at the nucleic acid level, can be used for preventing and purifying classical swine fever in an intensive pig farm, and has a considerable application prospect.

The invention discloses a construction method of a nocardia seriolae mycolic acid deficient strain, which belongs to the technical field of aquaculture prevention and control, and comprises the following steps: strain and material preparation, culture and genome extraction, upstream and downstream fragment cloning to construct deletion plasmids, competent cell preparation, electrotransformation and screening, and biological characteristic and toxicity analysis. The nocardia seriola seriola mycolic acid defect type strain is constructed and compared with a wild strain and a back-filling strain for research, the effect of the mycolic acid in the aspects of growth, form, toxicity and the like of thalli can be defined, the relationship between the mycolic acid and the pathogenicity of the thalli can be deeply known, and an important clue is provided for revealing the pathogenic mechanism of the nocardia seriola seriola.

The invention discloses an application of an ALKBH9B gene in promotion of plant callus formation, belongs to the technical field of gene engineering, and provides an application of the ALKBH9B gene in promotion of plant callus formation. The invention also provides an application of an expression cassette, a vector or a recombinant bacterium containing the ALKBH9B gene in promoting formation of poplar leaf calluses. The ALKBH9B gene is knocked out, the expression quantity of the ALKBH9B gene is reduced, it is found that when the gene editing strain with the knocked-out gene is cultured on a callus induction culture medium for 5 days, callus tissue starts to be formed, the callus forming speed is high, and the net weight of the callus and the callus generation rate are remarkably higher than those of a wild strain. The result shows that ALKBH9B has an inhibition effect in the process of inducing the callus by the leaf, and the deletion of ALKBH9B can promote the formation of the callus.

The invention relates to a monoclonal antibody DIDA55 aiming at hog cholera virus, and a preparation method and application thereof, belonging to the field of medical preparations. The monoclonal antibody DIDA55 or an antigen binding fragment thereof comprises a heavy chain variable region and a light chain variable region, amino acid sequences of LCDR1, LCDR2 and LCDR3 in a light chain variable region of the antibody are shown as 24th to 34th, 50th to 56th and 89th to 97th in SEQ ID No: 4; amino acid sequences of HCDR1, HCDR2 and HCDR3 in a heavy chain variable region of the antibody are shown as the 31st to 35th, the 50th to 65th and the 95th to 102th of SEQ ID No: 5. The monoclonal antibody provided by the invention can be used in the fields of swine fever E2 protein labeled subunit vaccine immunity, serological diagnosis of wild strains, swine fever vaccine immune effect evaluation, related experiments and the like, and provides antibody resources for prevention, control and purification of CSF.

The invention belongs to the technical field of biology, and particularly relates to a human metapneumovirus mouse adapted strain and application thereof. Compared with a wild strain, the strain has higher susceptibility to animals; the strain can be used for treating BALB / c mice and can cause typical clinical symptoms and even death, for example, after the strain infects the BALB / c mice, the disease symptoms are obvious, the weight of 83% infected mice is severely reduced to 75% or below and reaches the humanity killing standard, and the death rate reaches 50% or above 4 days after the strain infects the BALB / c mice; the strain can be used for constructing a cell model or an animal model of human metapneumovirus infection or diseases caused by the human metapneumovirus infection, and is further used for screening drugs for preventing and / or treating the human metapneumovirus infection or the diseases caused by the human metapneumovirus infection. In addition, the strain can also be used for preparing medicines for preventing and / or treating human metapneumovirus infection or diseases caused by the human metapneumovirus infection, preparing antibodies or antiserum for resisting the human metapneumovirus and the like.

The invention discloses an application of an isoeugenol monooxygenase mutant in production of isoeugenol vanillin, which comprises the steps of recombinant strain construction, fermentation culture of recombinant strains and catalytic reaction of fermentation broth, and the isoeugenol monooxygenase mutant is mutated through an isoeugenol monooxygenase amino acid sequence of wild fungi WT. And the thalli are expressed by escherichia coli, so that a series of thalli with a promoting effect on the catalytic efficiency of vanillin production are formed. The mutant super-efficient enzyme catalyst with the catalytic conversion rate reaching up to 98.5% or above is obtained through screening, the defects of low efficiency, pollution, high energy consumption and the like of traditional chemical catalyst production are overcome, and the mutant super-efficient enzyme catalyst is more suitable for green industrial production requirements and worthy of being popularized to industrial use.

The invention discloses kluyveromyces marxianus and application of the kluyveromyces marxianus in production of single-cell protein by taking straw as a raw material. The Kluyveromyces marxianus is a ZH-2 bacterial strain which is CGMCC (China General Microbiological Culture Collection Center) No.32295 The strain is obtained from a wild strain in a laboratory adaptive evolution mode, wheat straw and an inorganic nitrogen source can be used as raw materials for efficiently producing single-cell protein, compared with a parent strain, the utilization speed and the utilization rate of biomass, glucose and xylose are remarkably increased, the yield of ZH-2 SCP can reach 0.047 g.g <-1 >, and the yield of ZH-2 SCP can reach 0.045 g.g <-1 >. And the essential amino acid mode basically accords with adult and infant amino acid modes, and can be used as high-quality protein nutrition supply. The Kluyveromyces marxianus ZH-2 strain capable of obtaining single-cell protein by fermenting wheat straw as a raw material is provided from the perspective of utilizing cheap waste resources, so that the production cost of SCP is greatly reduced, and the problem of protein resource shortage is effectively solved.

Provided are an Aeromonas dhakensis mutant strain with deletion of a surface polysaccharide synthesis gene, a complemented strain, a construction method therefor, and the use thereof. The mutant strain is obtained by deleting one or more of ugd, ugd2, and cap1J from the Aeromonas dhakensis wild strain A. dhakensis C160501.

The invention relates to the field of microorganisms, in particular to bacillus velezensis and application of the bacillus velezensis in preparation of surfactin, the preservation number is CCTCC NO: M 20251689, the bacillus velezensis is a wild type bacillus velezensis strain, and the surfactin yield of the bacillus velezensis is 2-3 times higher than that of a conventional wild strain. At the shake flask level, the yield of the surfactin reaches 10.4 g / L, when fed-batch fermentation is carried out in a 5L fermentation tank, the yield reaches 22.3 g / L, the yield and production intensity are higher than the currently known wild fungus fermentation level, and the method has huge industrial application potential.

The invention discloses a schizochytrium limacinum strain for efficiently converting kitchen waste to produce single-cell protein and application of the schizochytrium limacinum strain, and belongs to the technical field of biological engineering. The preservation number of the schizochytrium sp LOX-2 is CGMCC (China General Microbiological Culture Collection Center) No. 41623. The invention also discloses a method for producing single-cell protein by efficiently converting kitchen waste. The method comprises the following steps: fermenting food waste to produce volatile fatty acid; and culturing schizochytrium limacinum by using the strain as a carbon source to obtain single-cell protein. According to the recombinant strain spLOX-2, the utilization of lactic acid is improved, the biomass and the protein yield of the recombinant strain spLOX-2 are respectively improved by 14.19% and 12% compared with those of a wild strain, and the grease content is obviously improved by 107.1%. According to the invention, a new way is provided for a sustainable biological economic mode, wastes are converted into valuable biological chemicals, and a solid foundation is laid for expanding the scale of the process and the economic feasibility of the process in industrial application.

The invention provides a nucleic acid probe, a primer group, a kit, a detection method and application, and relates to the technical field of biology. The nucleotide sequence of the nucleic acid probe is as shown in SEQ ID NO. 1; wherein the 3'end of the nucleic acid probe is modified with MGB, and locked nucleic acid is modified at a base position corresponding to the difference between the swine fever wild strain and the swine fever vaccine strain in the nucleotide sequence. According to the nucleic acid probe, a specific sequence is utilized to precisely target a swine fever wild strain, and locked nucleic acid modification is introduced at a differential site, so that the recognition capability on single-base mismatch is remarkably enhanced, non-specific binding to a vaccine strain is thoroughly blocked, and false positive interference is eliminated; and 3 '-terminal MGB modification is matched to improve the binding stability and sensitivity, so that the efficient and accurate identification of the swine fever wild strain under the immune background is ensured.

The invention discloses a pig intestine organoid and lymphocyte co-culture system as well as a construction method and application thereof, and belongs to the technical field of virus culture. The co-culture system is obtained by co-culturing porcine ileum organs and porcine small intestine epithelium lymphocytes. By using the co-culture system, the PEDV still can infect the organoid under the condition of not adding pancreatin, and by using the co-culture system to separate and culture the PEDV wild strain, the pathological change of the organoid can be observed during blind passage of the fourth generation, and at the moment, the pathological change does not appear on Vero cells. Reverse transcription-polymerase chain reaction (RT-PCR) identification finds that a stripe can be amplified after a PEDV wild strain is continuously passed for five generations on the co-culture system, and no stripe can be amplified after the PEDV is continuously and blindly passed for five generations on Vero cells no matter whether pancreatin is added or not. The proposal of the invention is of great significance to understanding the pathogenesis of PEDV and developing new drugs and therapies for preventing PEDV infection.

The invention belongs to the technical field of virus detection, and discloses a digital PCR (polymerase chain reaction) kit for simultaneously detecting African swine fever virus, porcine reproductive and respiratory syndrome virus and swine fever virus, and the kit comprises primers and probes as shown in SEQ ID NO.1-SEQ ID NO.24. After a single system of an African swine fever virus-VP72 gene, an African swine fever virus-CD2V gene, an African swine fever virus-14L gene, a porcine reproductive and respiratory syndrome virus-RdRP gene, a porcine reproductive and respiratory syndrome virus-European strain, a porcine reproductive and respiratory syndrome virus-American strain, a swine fever virus-vaccine strain and a swine fever virus-wild strain is tested, a nine-fold digital PCR system containing an internal standard is established; through tests of indexes such as linearity, specificity, minimum detection limit, repeatability, comparison of a single digital PCR system and a multiple digital PCR system, the currently developed digital PCR multiple detection kit completely meets development requirements and is high in specificity and sensitivity, and the minimum detection limit of the digital PCR multiple detection kit can reach 10 Copies / mu L or below.

The present invention belongs to the field of selective culture of microorganisms and relates to a detection medium for Burkholderia cepacia complex in a pharmaceutical water system. A detection medium for Burkholderia cepacia complex in a pharmaceutical water system, the formula (g / L) of the detection medium is: peptone 0.5 - 2.0 g, sodium pyruvate 1 - 4 g, carbon source 1 - 4 g, yeast extract 0.5 - 2.0 g, casein amino acid 1 - 4 g, magnesium sulfate 0.05 - 0.2 g, and the solvent is water. The inventor has screened a detection medium for Burkholderia cepacia complex in a pharmaceutical water system with special components. Through the culture experiment of Burkholderia cepacia complex, it is found that whether it is a standard strain or a wild strain isolated from a pharmaceutical water system, within the same culture time, the OD 600 value results of 1 / 10 TSB and R2A liquid media do not exceed 0.5, while the bacterial concentration in the detection (BCB) medium for Burkholderia cepacia complex in a pharmaceutical water system is significantly higher than that in 1 / 10 TSB and R2A liquid media.

The invention belongs to the technical field of biology, and particularly relates to a 3D protein mutated O-type foot-and-mouth disease recombinant virus strain as well as construction and application thereof. The 403th methionine of the O-type foot and mouth disease virus 3D protein is mutated into alanine, the recombinant virus strain rFMDV-M403A with the mutated O-type foot and mouth disease virus 3D protein is successfully constructed and saved by using a reverse genetic technology, and amino acid of the recombinant virus strain can be stably mutated in a passage process; the growth speed of the mutant strain is slower than that of a wild strain, and the virus titer is remarkably reduced; in an individual experiment, neonatal mouse infection shows that the mutant strain can improve the survival rate of neonatal mice, and the virus load and tissue lesion in the liver are remarkably reduced. The attenuated foot-and-mouth disease recombinant virus strain provided by the invention provides important significance for deep understanding of a foot-and-mouth disease virus pathogenic mechanism and a prevention and control strategy, and also provides an important theoretical basis for further development of a foot-and-mouth disease genetic engineering vaccine.

The invention relates to the technical field of microorganisms, and particularly discloses pseudomonas oryzae NKP20, a microbial agent and application of the pseudomonas oryzae NKP20. The pseudomonas oryzae NKP20 (CCTCC NO: M 2024730) provided by the invention can be used for quickly converting mineral phosphorus stably existing in rock or soil into an effective form which can be absorbed by plants in a large proportion and at low cost. After the pseudomonas oryzae NKP20 is cultured in a phosphorus-containing rock liquid culture medium for 3 days, the phosphorus dissolving amount can reach 300 mg / L, and the phosphorus dissolving amount can reach 30%; the phosphate solubilizing amount can reach 400 mg / L after 7 days of culture, and the phosphate solubilizing amount can reach 40%. According to the invention, the pseudomonas oryzae NKP20 is combined with the phosphate solubilizing capacity of soil and the phosphate solubilizing capacity of rock, and reference is provided for later research of wild strains. When the microbial fertilizer is applied to crops, the phosphorus dissolving effect can be achieved, the crop yield can be obviously increased, and meanwhile the yield can be increased in successive years.

The invention belongs to the technical field of biological detection, and particularly relates to an SNP (Single Nucleotide Polymorphism) site for distinguishing a mycoplasma synoviae MS-H vaccine strain and a wild strain, a kit and application, and target genes meeting detection requirements are screened out by carrying out bioinformatics comparative analysis on whole genomes of MS-H and parent strains thereof. A specific primer and an MGB probe are designed for a specific conserved gene sequence ktrB gene for the first time, and the double qPCR kit for distinguishing the MS-H vaccine strain and the wild strain is established. In-vitro experiments prove that the kit disclosed by the invention is simple to operate, high in sensitivity, strong in specificity and good in repeatability. The screened gene loci and the established detection kit have the advantages that the defect that at present, common genes are prone to reverse mutation is overcome, the method can be used for clinical rapid diagnosis of MS vaccine strains and wild strains, the detection accuracy is improved, population purification is promoted, and certain commercial value is achieved.

A nanobody classical swine fever virus (CSFV)-E0-Nb1 against a CSFV E0 protein, and an encoding gene and use thereof are provided, belonging to the technical field of biological detection. The nanobody CSFV-E0-Nb1 has an amino acid sequence shown in SEQ ID NO: 1 and can be expressed using an expression system. The nanobody is coupled with a quantum dot to obtain an immunochromatographic test strip for distinguishing antibodies against a CSFV E2 subunit vaccine strain from those of a wild strain infected on site, and there is a simple production process of the test strip. The immunochromatographic test strip can differentiate and diagnose the antibodies against the CSFV E2 subunit vaccine strain and the wild strain, and has the advantages of rapid, convenient, and instant detection, thus providing a new method for the detection of classical swine fever (CSF) purification.

The invention relates to the technical field of agricultural biology, in particular to application of a regulatory gene Mt2312847 in improving the cellulase expression quantity of mycelia thermophila. Through interference or knockout of a regulatory gene Mt2312847 of a wild strain of the mycelia thermophila and knockout of the strain (Mt delta 2312847), the cellulase concentration of fermentation liquor of the interference strain is higher than that of the wild strain, and the CMCase enzyme activity of the Mt delta 2312847 and the CMCase enzyme activity of the Mt delta 2312847 are 2.2 times and 1.6 times that of a control strain.