8 results about "Gene deletion mutation" patented technology

The invention relates to a Pseudomonas plecoglossicida pldB gene deletion mutant strain and a preparation method and application thereof, and belongs to the technical field of microorganisms and the field of algae preservation, the pldB gene of the mutant strain is deleted or inactivated, the nucleotide sequence of the pldB gene is shown as SEQ ID NO: 1, and the GenBank accession number of the Pseudomonas plecoglossicida is CP031146.1. The virulence of the mutant strain is obviously reduced compared with that of a wild strain of pseudomonas plecoglossicida; the strain can induce appropriate immune response of a host and up-regulate expression of anti-inflammatory factors, is beneficial to relieving immune pathological injury, has good attenuated live vaccine potential, and provides a brand new vaccine candidate strain for prevention and control of the visceral white-spot disease of the large yellow croaker.

The application discloses a rice OsNAR1 application of the gene or the coded protein in regulating rice resistance to Magnaporthe oryzae, and relates to the technical field of rice Magnaporthe oryzae prevention and treatment. OsNAR1 The CDS nucleotide sequence of the gene is shown as SEQ ID No. 2. OsNAR1 The application finds that the rice gene OsNAR1 plays an important role in the process of rice resistance to Magnaporthe oryzae, the number of leaf spots on the gene deletion mutant is less, the gene can be used for screening rice strains resistant to Magnaporthe oryzae, the expression amount of a basic resistance marker gene in the gene deletion mutant is significantly up-regulated, and it is indicated that OsNAR1 negatively regulates the expression of the basic resistance gene and can be used for preventing and treating Magnaporthe oryzae.

The application belongs to the field of genetic engineering and medical engineering, and discloses virK Application of gene in regulation of Klebsiella pneumoniae virulence. The application finds that the expression level of the gene is significantly increased in polymyxin-resistant mutant strains through transcriptome analysis, virK Further research shows that the expression of the gene is regulated by the PhoP / PhoQ two-component regulatory system. The application constructs virK Gene deletion mutant strains and complementary strains, and compares the virulence difference of the strains in an animal infection model, finds that virK The virulence of the deletion strain is significantly reduced, and the complementary strain can restore the virulence phenotype, indicating that virK The gene plays an important role in the regulation of Klebsiella pneumoniae virulence. The application first finds that PhoP can regulate virK Gene expression, and affects the virulence phenotype of Klebsiella pneumoniae through the regulation pathway, thereby revealing a new virulence regulation mechanism, and providing a theoretical basis for subsequent targeted intervention.

The present application relates to the field of biotechnology, in particular to the application of glycoside hydrolase FsGH28c and its coding gene in regulating pathogenicity of a bacterial strain. The present application provides a glycoside hydrolase coding gene FsGH28c related to the development of Fusarium solani pisi, the utilization of carbon source and pathogenicity. After knocking out the FsGH28c gene of Fusarium solani pisi, the spore production of Fusarium solani pisi is reduced, the spore development is deformed, and the utilization rate of carbon source (especially pectin) is reduced. In addition, the amount of fungal colonization at the root of the host pepper and the pathogenicity of the FsGH28c gene deletion mutant are reduced. The FsGH28c gene of the present application positively regulates the pathogenicity of Fusarium solani pisi, and can be used as an important candidate gene for the study of the pathogenic mechanism of Fusarium solani pisi.

This invention discloses a *Lactobacillus paracasei* S-NB gene deletion mutant strain, its construction method, and its application. The S-NB gene deletion mutant strain uses *Lactobacillus paracasei* S-NB as the starting strain, and the mutant strain contains *Lactobacillus paracasei* S-NB gene deletion mutants. cps The upstream segment of the gene was knocked out by the plasmid. cps Upstream homologous arm gene substitution in *Lactobacillus paracasei* S-NB cps The downstream gene fragment carried by the knockout plasmid cps Gene substitution in the downstream homologous arm of the gene; among which, cps The gene base sequence of the upstream homologous arm is shown in SEQ ID NO:1. cps The downstream homologous arm gene base sequence is shown in SEQ ID NO:2. Compared with traditional methods, the success rate of knockout vector construction in this invention reaches over 95%, and the operation is simple, time-saving, and the operation cycle is only 6-7 days; the knockout vector constructed using this invention can knock out Lactobacillus paracasei S-NB. cps Genes, the result cps Gene deletion mutants are unaffected in growth, but their capsule layer becomes thinner and their ability to produce biofilm decreases.

The present application belongs to the field of plant disease control research, and relates to a cucumber multi-host coelomyces effector protein CcSP1, a coding gene thereof and application. The present application provides a new cucumber multi-host coelomyces effector protein CcSP1, a coding gene thereof and application. The nucleotide sequence of the coding gene of the multi-host coelomyces effector protein CcSP1 is shown as SEQ ID NO. 1. Transient expression of the CcSP1 gene in N. benthamiana can inhibit hypersensitive necrosis caused by N. benthamiana. A gene deletion mutant ΔCcSP1 is constructed by homologous recombination, and the deletion of the gene does not affect the vegetative growth, but significantly reduces the pathogenicity when invading the cucumber leaves. It is shown that CcSP1 is involved in the lesion expansion of the plant after the invasion of the multi-host coelomyces, and plays an important role in the pathogenic process of the multi-host coelomyces. The present application has important significance for analyzing the related molecular mechanism of cucumber coelomyces leaf spot and establishing the comprehensive control technology strategy of the plant cucumber coelomyces leaf spot.

The invention belongs to the technical field of microorganisms and genetic engineering. The invention provides a listeria monocytogenes strain as well as a preparation method and application thereof, the flagellum formation ability of the strain is enhanced, the environmental stress resistance is enhanced, and the immune recognition of host cells on listeria monocytogenes can be enhanced; the strain is subjected to delta yxeA gene deletion mutation; the bacterial strain is named as Listeria monocytogenes Lm-delta lmo2568, the preservation number of the bacterial strain is CGMCC (China General Microbiological Culture Collection Center) No.36001, and the bacterial strain is preserved in the China General Microbiological Culture Collection Center on September 22, 2025. The invention finds that the deletion of Listeria monocytogenes YxeA promotes the formation and expression of flagellum, and the obtained strain can enhance the immune recognition of host cells on Listeria monocytogenes, and can be used for preparing related preparations.