57 results about "Flagellum" patented technology

The invention discloses gene-simplified bacillus subtilis for producing surfactin and application of the gene-simplified bacillus subtilis, and belongs to the technical field of gene engineering. According to the method disclosed by the invention, the variety of non-essential genes is determined by analyzing and identifying the bad performance influencing the fermentation production of the surfactin by the bacillus subtilis. Therefore, on the basis of the bacillus subtilis 168, a phosphopantetheinyl transferase (sfp) gene is firstly integrated, so that the surfactin production capacity of host bacteria is recovered; then, genes (clusters) in five aspects of a biological membrane synthesis pathway, a metabolic by-product pathway, spore generation, a protease system and flagellum generation are simplified. After the strain EX10 is simplified, the fermentation performance is optimized, and the fermentation yield reaches up to 11.2 g / L, which is 2.1 times higher than that of the original strain. Therefore, the genome-simplified strain has a good application prospect as a chassis cell for industrially and efficiently producing surfactin.

The invention discloses a method for evaluating the environmental risk of perfluorooctane sulfonic acid by using euglena gracilis, and belongs to the field of environmental pollutant biological monitoring and ecotoxicology evaluation. The method comprises the following steps: detecting the photosynthetic activity and the movement ability of Euglena gracilis exposed to perfluorooctane sulfonic acid with environmental concentration and the organelle distribution condition of the perfluorooctane sulfonic acid in euglena gracilis cells in situ; the photosynthetic activity comprises in-situ monitoring of chlorophyll fluorescence parameters and maximum non-photochemical quenching coefficient of euglena gracilis, and quantitative analysis of chloroplast pigment content; the movement ability comprises horizontal light-driving movement speed and vertical light-driving movement speed measurement of the euglena gracilis and flagellum shedding rate calculation. The method breaks through the limitation of a traditional single autotrophic mode, reveals a regulation and control mechanism of nutritional conditions on toxic effects, provides a scientific basis for water environment safety monitoring and optimization, and has the advantages of being convenient to operate and low in cost.

The invention discloses application of flagellimonas sp. SN16, and relates to the field of application of microorganisms. The strain is preserved in Guangdong Microbial Culture Collection Center, and the preservation number is GDMCC No. 65745. The culture supernatant has efficient algae-killing activity on free single cells and cysts of the globocystis globosa, and algae cells can be split after the culture supernatant is treated for 12 hours. In a red tide field experiment of the spherocystis globosa, the algae killing effect on the cysts is good, and the treated water body has no obvious biotoxicity. In addition, the algae-killing activity of the supernatant is kept stable in an environment with the temperature of-20 to 100 DEG C and the pH value of 2 to 12. The flagelmonas and the culture supernatant thereof provided by the invention have important application value in the field of biological treatment of the algal blooms of the globocystis globocystis, are expected to become an efficient and safe algicide, effectively treat the algal blooms of the globocystis globocystis and protect the marine ecological environment.

The invention discloses a method for culturing low-temperature aerobic granular sludge, and relates to the technical field of sewage treatment, and the method adopts a high-concentration dissolved oxygen (DO) aeration and long-period operation mode to improve the tolerance and adhesion capacity of microorganisms to a low-temperature environment by enhancing the carbon metabolism capacity and extracellular polymeric substance secretion of the microorganisms. Meanwhile, the operation mode of combining high aeration and mechanical stirring not only can generate larger shearing force to remove loose biological membranes on the surface of the sludge, but also can enhance the aggregation ability of the microorganisms by promoting quorum sensing phenomena among fimbriae, flagellum and the microorganisms. The intermittent operation mode creates a satiation-starvation environment for the growth of microorganisms, and further enhances the stability of the particles. Along with shortening of the operation cycle, the system can further complete particle screening, and the low-temperature-resistant aerobic granular sludge with high settleability is reserved.

The application discloses an oral nano-vaccine and a preparation method and application thereof, and relates to the technical field of immunology, and specifically discloses an oral nano-vaccine which comprises a nano-particle wrapped by a biomimetic bacterial membrane vesicle and an outer layer; the nano-particle comprises an antigen and a biodegradable polymer material; the biomimetic bacterial membrane vesicle comprises an ionizable flagellar lipoprotein, an immune adjuvant, a phospholipid, a sterol lipid and a polyethylene glycol lipid; and the outer layer is a pH-responsive polymer. The oral nano-vaccine provided by the application combines the immune activation advantages of natural bacterial membrane vesicles and the precise regulation characteristics of synthetic materials, significantly improves the transmembrane penetration capacity of the antigen in the intestinal epithelium and the overall activation effect of the mucosal immune system. The oral nano-vaccine provided by the application can protect the antigen and the immune adjuvant from degradation and realize precise release in the intestinal microenvironment; and the oral nano-vaccine significantly improves the bioavailability and safety of an oral tumor vaccine, and lays a key technical foundation for clinical transformation and large-scale production of the oral tumor vaccine.

The application provides a flexible flagellum-driven swimming micro-nano robot and a control method thereof, and relates to the technical field of micro-nano robots.The robot comprises a head and a flexible flagellum, the inside of the head is provided with a control component, a monitoring component, a driving component and a power source, the driving component is connected with the flexible flagellum, and the method comprises the following steps: a control chip reads chemical concentration or light field intensity information detected by an environmental sensor; the collected chemical concentration or light field intensity information is compared with historical time information; the driving frequency of a micro-actuator is switched according to the comparison result; and the swimming micro-nano robot is driven to swim.The application fully utilizes the complex fluid-structure coupling behavior between the flexible flagellum and the fluid, does not need a complex steering mechanism, only needs simple information storage and logical judgment to change the swing frequency of the flagellum, and can realize the autonomous navigation movement of the micro-nano robot in a complex environment, and gradually approaches the target along a variable-parameter spiral trajectory.

The application provides a preparation method of a biomimetic flagelliform nanowire and relates to the technical field of nanowire material preparation. The method comprises the following steps: mixing and immersing a trithiocyanic acid solution and copper hydroxide nanowires, and obtaining immersed nanowires after drying; the immersion conditions comprise the following steps: the temperature is 20-45 DEG C, and the time is 0.01-50 min; and the obtained immersed nanowires are calcined at 250-500 DEG C for 2-6 h. The method provided by the application uses a trithiocyanic acid solution to immerse Cu(OH)2 nanowires, and then calcines in a muffle furnace. The method provided by the application is simple in operation, the prepared nanowires are uniform and controllable in morphology, and can be applied to the fields of oil-water separation, battery negative electrode current collectors, adsorption and the like.

The application discloses a kind of biological hybrid micro machine population oral delivery system of imitating Helicobacter pylori survival mechanism, belong to oral stomach medicine delivery technical field.The system is by active power module (flagellum driven chlamydomonas reinhardtii), environmental regulation module (acid urease modified on algal surface) and multifunctional load module (macrophage membrane wrapped drug-loaded nanoparticles) synergistic assembly through polydopamine (PDA) spatial conformation control layer is formed.Active power module utilizes self-movement ability to penetrate mucus barrier and extend intracavity retention time to 12 hours or more;Environmental regulation module produces local alkalization effect by catalyzing urea hydrolysis, provides chemical shield for system in extremely acid environment of pH 1.0-3.0, protects active power module from gastric acid inactivation;Multifunctional load module is accurately delivered to gastric epithelial cells by inflammation targeting effect, such as CRISPR / Cas9 biological macromolecule, and realizes up to 31.8% in-vivo gene editing efficiency.The application provides a non-invasive, modular active delivery platform for the precise treatment of gastric diseases such as gastritis through the synergistic effect of physical penetration, metabolic reprogramming and gene intervention.

This invention discloses a high-precision flow field sensor and measurement method with a multi-stage flagella structure inspired by mosquito antennae. The biomimetic flow field sensor consists of a central rigid rod and two multi-stage cantilever sensors on both sides. The cantilever sensors are composed of a flexible bottom layer, a flexible top layer, and a piezoresistive flexible sensor. The central rigid rod provides fixation and support for the multi-stage cantilever sensors. The flexible bottom layer is made of a high-elastic-modulus material and mainly senses changes in airflow in the surrounding flow field, oscillating with the airflow. The flexible top layer is made of a low-elastic-modulus material and mainly enhances the sensitivity of the rigid front section to changes in airflow. The piezoresistive flexible sensors are distributed on a secondary cantilever beam composed of the flexible bottom and upper layers. The oscillation of the secondary cantilever beam causes deformation of the two layers of piezoresistive flexible sensors, thereby changing the sensor resistance value. By comprehensively evaluating the resistance change of the piezoresistive flexible sensors, information such as the flow direction, flow rate, and velocity of the airflow in the flow field can be accurately measured.

The invention provides a bionic flagellum actuator based on a bacterial flagellum structure and a preparation method. The bionic flagellum actuator comprises a flexible hook which is of a pre-bent arc-shaped structure, mechanical interfaces with protruding platforms are arranged at the two ends of the flexible hook, and a reinforcing framework is embedded in the flexible hook; the flagellum filament is of a gradient cross section circular truncated cone structure and is composed of a silica gel base body, an internal elastic support and an external woven mesh pipe. The modular interface comprises a hook end flange connecting piece and a driving end quick release buckle; the flexible hooks and the flagellum filaments are mechanically interlocked through the protruding platform to be integrally formed in a casting mode, the woven net pipe restrains radial expansion of the flagellum filaments, and the elastic support induces directional bending deformation. The actuator has high flexibility, high environmental adaptability and easy maintainability, can adapt to different load scenes by adjusting the material hardness, the section gradient and the pre-bending angle, and provides an efficient and low-cost solution for the field of flexible driving.

The invention provides application of piceatannol in preparation of a salmonella flagellum inhibitor, and belongs to the technical field of biological medicines. Through analysis of salmonella sliding motion test, biofilm formation test, salmonella cell invasion test and other tests, it is found that piceatannol down-regulates flagellum-related gene transcription, weakens the sliding capacity, reduces biofilm formation and weakens the invasion capacity to host cells at non-inhibitory concentration; the invention relates to a salmonella flagellum inhibitor, particularly relates to a salmonella flagellum inhibitor, supports the development value of the salmonella flagellum inhibitor as an anti-virulence drug, provides a non-bactericidal treatment strategy capable of remarkably weakening bacterial pathogenicity, can be used as a potential lead compound or a composition therapy component for treating salmonella infection, and is applied to production and preparation of the salmonella flagellum inhibitor.

The application provides an application of a grass Wu extract, relates to the field of bacteriostatic technology, and is used for inhibiting growth of escherichia coli; the minimum bacteriostatic concentration of the grass Wu extract is 2.5 mg / mL; the grass Wu extract can directly destroy the cell wall and the cell membrane of bacteria, down-regulate key genes of a flagellum assembly path, interfere with a core metabolic path of bacteria, and down-regulate related genes such as a two-component system and ABC transporter proteins; the MIC of the grass Wu extract on escherichia coli is determined as 2.5 mg / mL for the first time, which provides an accurate dose basis for developing the grass Wu extract into an antibacterial preparation, proves that the grass Wu extract has a definite and quantifiable direct bacteriostatic effect; meanwhile, through a multi-target attack strategy of 'breaking a membrane'-'breaking a leg'-'breaking food'-'causing blindness', the bacteria are difficult to produce drug resistance through a single mutation, and a new idea is provided for solving the problem of antibiotic drug resistance.

The invention relates to the field of biotechnology engineering, in particular to recombinant escherichia coli based on cyanamide-induced flagellum assembly genes as well as a construction method and application of the recombinant escherichia coli. The recombinant escherichia coli based on the cyanamide-induced flagellum assembly gene is constructed by overexpressing the flagellum assembly gene driven by a cyanamide-induced promoter into escherichia coli 045. The recombinant Escherichia coli can strengthen the formation of a biological membrane, and the formation of the biological membrane is strengthened by adding cyanamide to precisely regulate and control the expression of a flagellum assembly gene in the process of preparing L-valine through fermentation. When the recombinant escherichia coli is used for preparing the L-valine through fermentation, the yield of the L-valine is increased, the fermentation efficiency is improved, and the fermentation period is shortened. The method has the advantages that the method is simple and convenient to operate, the cell can be recycled in the immobilized fermentation of the L-valine, the cost is saved, the continuity of the whole fermentation is enhanced, and a cell immobilization strategy based on a biological membrane is provided for the engineering application of an L-valine production system.

The invention belongs to the field of biology, and discloses a proteus mirabilis homologous recombination system expression plasmid which comprises a pBR322 replication starting point, a resistance gene, an arabinose inducible promoter and a proteus mirabilis-derived homologous recombination operon. The homologous recombination operon is used for coding a TPM66325 protein, an EPM66325 protein, a single-chain binding protein SSB and a fake release protein. The expression plasmid has relatively high recombination efficiency in proteus mirabilis GDMCC 66325 and can also play a recombination role in a proteus mirabilis standard strain ATCC35659, and the expression plasmid is obtained by knocking out a related gene bcsB formed by a hemolysin related gene hpmA and a biological membrane of the proteus mirabilis GDMCC 66325 and directly knocking in a heterologous gene after a related gene cluster is adjusted by flagellum. The effectiveness of the expression plasmid in recombinant operation of proteus mirabilis is verified; meanwhile, the invention further discloses a proteus mirabilis homologous recombination system, application and a gene knockout / knockin method.

This invention discloses the pharmaceutical applications of a P2Y11-specific inhibitor and compositions containing it, belonging to the field of biomedical technology. This invention discloses for the first time the use of NF157 in the preparation of drugs related to the treatment of HD5-induced pathogen infection. In combating pathogen infection, NF157 can specifically inhibit the binding of P2Y11 to HD5, thereby eliminating the role of HD5 in regulating cytoskeleton rearrangement and promoting filopodia formation, thus becoming a key link in interrupting pathogen infection. By preventing the formation of filopodia, NF157 effectively blocks the bacterial capture pathway, showing significant intervention effects on some pathogens that lack adhesion devices and flagella and rely on cellular pseudopodia capture for invasion.

The application discloses a kind of methods for measuring the movement direction of flagellum algae under flow conditions, the method comprises the following steps: step 1, image sequence acquisition and processing;Step 2, cell image cropping alignment;Step 3, cell image pre-processing;Step 4, create fan ring detection area;Step 5, construct timing frame;Step 6, time sequence difference feature calculation;Step 7, confidence calculation and movement direction determination.The method for measuring the movement direction of flagellum algae under flow conditions disclosed in the application overcomes the technical problems that cannot be identified due to poor imaging quality of flagellum and loss of instantaneous information in moving water environment, and realizes high-precision, automated and continuous measurement of the movement direction of flagellum algae through time sequence dynamic feature analysis and biological motion characteristic determination.

The application provides a kind of lipopeptide compound PW-1 and its preparation method and application in preventing and controlling bacterial wilt, belong to biological pesticide technical field;The PW-1 is prepared by fermentation, solvent extraction, acidification and reverse phase chromatography from Paenibacillus polymyxa (P. Paenibacillus polymyxa ) strain DW-7A;The core of the compound is that it plays a role through "anti-toxicity" mechanism, at the concentration without inhibiting the growth of Pseudomonas solanacearum (P. Ralstonia solanacearum ), can specifically interfere with the biosynthesis of pathogenic bacteria flagellum, cause its motility, chemotaxis and early infection ability to decrease significantly;Pot experiment proves that the relative control efficiency of PW-1 to tobacco bacterial wilt reaches 62.2%, and has no effect on the growth of soil bacillus at the concentration of up to 1000 μg / mL, shows efficient, targeted and environment compatible characteristics;The application provides a new candidate compound and key technical support for the development of green pesticide targeting flagellum.

The invention provides 3D sea urchin-shaped copper telluride nano-enzyme hydrogel, a preparation method thereof and application of the 3D sea urchin-shaped copper telluride nano-enzyme hydrogel in preparation of gram-negative bacterium resisting drugs, and belongs to the technical field of inorganic nano-enzymes. The copper telluride nano-enzyme hydrogel provided by the invention can be used for specifically and selectively treating gram-negative bacterium infection due to the fact that 3D sea urchin-shaped copper telluride has double-enzyme activity of oxidase-like and glutathione-like oxidase, and biosynthesis of lipopolysaccharide (LPS) and flagellum can be interfered by consuming glutathione (GSH); the attack ability of reactive oxygen species (ROS) generated by catalysis is enhanced, so that drug-resistant gram negative bacteria and biological membranes thereof can be specifically removed. Besides, the 3D urchin-like copper telluride nano-enzyme hydrogel can significantly inhibit pseudomonas aeruginosa infection and inflammatory response on burn wounds, promotes angiogenesis and cell proliferation at the same time, and has a good treatment effect on the burn wounds infected by pseudomonas aeruginosa.

The invention discloses a dyeing method for vagina micro-ecology detection. The dyeing method mainly comprises the following steps: 1) taking female genital tract secretions, and directly diluting the secretions with a diluent to form a suspension; (2) coating the suspension liquid on a glass slide by using a pipettor; 3) drying and fixing the suspension on the glass slide; 4) immersing the fixed suspension liquid glass slide into an eosin dye solution, and washing the glass slide with running water; (5) carrying out gram staining on the glass slide; and 6) observing by using a microscope. The invention also relates to a staining kit. According to the staining method, under the condition that the advantages of a gram staining method in the prior art are reserved, simple and rapid detection of trichomonad vaginalis can be achieved, the trophozoic form and flagellum form of trichomonad vaginalis can be clearly displayed, the accuracy of trichomonad vaginalis detection can be improved, and the method is suitable for popularization and application. The comprehensive and accurate detection on the vagina micro-ecology is facilitated.

The invention discloses a method for measuring the motion direction of flagellates under a flowing condition. The method comprises the following steps: step 1, acquiring and processing an image sequence; 2, cutting and aligning the cell image; step 3, preprocessing the cell image; step 4, creating a sector ring detection area; step 5, constructing a time sequence frame; step 6, calculating time sequence difference characteristics; and 7, calculating confidence and determining a motion direction. According to the method for measuring the motion direction of the flagellum under the flowing condition, the technical problem that the flagellum cannot be identified due to poor flagellum imaging quality and instantaneous information loss in a flowing water environment is solved, and high-precision, automatic and continuous measurement of the motion direction of the flagellum is realized through time sequence dynamic characteristic analysis and biological motion characteristic judgment.

Provided are delivery immunostimulatory bacteria that have enhanced colonization of tumors, the tumor microenvironment and / or tumor-resident immune cells, and enhanced anti-tumor activity. The immunostimulatory bacteria are modified by deletion of genes encoding the flagella, or by modification of the genes so that functional flagella are not produced, and / or are modified by deletion of pagP or modification of pagP to produce inactive PagP product. As a result, the immunostimulatory bacteria are flagellin and / or pagP−. The immunostimulatory bacteria optionally have additional genomic modifications so that the bacteria are adenosine or purine auxotrophs. The bacteria optionally are one or more of asd−, purI−, and msbB−. The immunostimulatory bacteria, such as Salmonella species, are modified to encode immunostimulatory proteins that confer anti-tumor activity in the tumor microenvironment, and / or are modified so that the bacteria preferentially infect immune cells in the tumor microenvironment, or tumor-resident immune cells, and / or are modified to induce less cell death in immune cells than in other cells. Also provided are methods of inhibiting the growth or reducing the volume of a solid tumor by administering the immunostimulatory bacteria.

The invention provides a method for promoting propagation of Hilasiosira wiskei and a microorganism used in the method. The microorganism used in the method is flagellimonas sp. FLG-A strain, and the preservation number of the FLG-A strain is CGMCC No.34666. The invention further provides a method for promoting propagation of Hilasiosira wiskei. The flagelmonas FLG-A strain provided by the invention can effectively improve the propagation effect of the sealasiosira wissi, and has good production and application prospects.

The present invention relates to a method for reconstructing the three-dimensional motion of sperm flagella based on deep learning, comprising the steps of: obtaining a two-dimensional image of a sperm to be processed, performing image preprocessing on the two-dimensional image of the sperm to be processed, and obtaining a preprocessed image; inputting the preprocessed image into a trained sperm segmentation model to obtain a binary image of the sperm flagellum; skeletonizing the binary image of the sperm flagellum to obtain the centerline of the sperm flagellum, N equidistant points, and the position coordinates corresponding to each equidistant point; obtaining N partial images of the sperm flagellum based on the N equidistant points, and inputting each partial image of the sperm flagellum into a trained depth prediction model to obtain depth information of each partial image of the sperm flagellum; and reconstructing a three-dimensional model of the sperm flagellum based on the depth information of each partial image of the sperm flagellum and the position coordinates corresponding to each equidistant point. The present invention provides a reliable solution for the study of sperm motility behavior and the development of assisted reproductive technology.

Escherichia coli flagellum is a potential target for research and development of escherichia coli infection anti-virulence drugs. Researches find that the Escherichia coli flagellum inhibitor has important significance on prevention and control of Escherichia coli The invention relates to a medical application of cinnamyl alcohol in preparation of an escherichia coli flagellum inhibitor, and tests such as an escherichia coli sliding motion inhibition test, a minimum inhibitory concentration determination test, a growth curve test, a greater wax moth survival rate test, an escherichia coli adhesion to Hela cell inhibition test and the like. It is verified that cinnamyl alcohol can inhibit bacterial flagellum-mediated electrophoresis on the premise that bacterial growth is not inhibited, and therefore the pathogenicity of escherichia coli is reduced. Cinnamyl alcohol exists in Peru balsam, cinnamon leaves, hyacinth oil, storax balsam and the like in an ester form, is commonly used as a fixative and a modifier, and is also an important medical raw material. Cinnamyl alcohol has the characteristics of low cost, no drug resistance and drug residue, has a wide application prospect, and provides a new way and a potential natural compound for prevention and treatment of escherichia coli infection.

The invention discloses a mixed nutritional flagellum and application thereof in promotion of tomato growth and prevention and control of bacterial wilt. The preservation number of the mixed nutritional flagellates NJAU-K1 is CCTCC (China Center For Type Culture Collection) NO: V202536. Experiments show that the mixed nutritional flagellum NJAU-K1 disclosed by the invention not only shows a remarkable growth promoting effect on tomatoes, but also can effectively prevent and control tomato bacterial wilt. The invention shows that the mixed nutritional flagellate NJAU-K1, as a novel plant growth promoting and biocontrol microorganism, shows great application potential in the aspects of crop yield increase and soil-borne disease control, and provides theoretical and technical support for green development of agriculture.

The invention discloses enterococcus faecalis and application thereof, and belongs to the field of bioengineering. The bacterium is preserved in the China Center for Type Culture Collection, the preservation number is CCTCC NO: M 20241843, the preservation date is August 26, 2024, the bacterium is separated from the root canal treatment of refractory periapical periodontitis in the stomatology department of the affiliated Yanan Hospital of the Kunming Medical University, the bacterium is a spore-free and flagellum-free double-spherical bacterium with the diameter of 0.9-1.1 mu m, and the preservation number is CCTCC NO: M 20241843. A biological membrane structure is efficiently and rapidly prepared and established through the bacterium and used for screening drugs capable of inhibiting enterococcus faecalis by removing an enterococcus faecalis biological membrane, and the drugs are further used for treating refractory periapical periodontitis caused by enterococcus faecalis infection.

The present invention discloses a method, device, and storage medium for dynamic observation of the three-dimensional morphology of sperm. The method comprises: obtaining a holographic image of the sperm, performing three-dimensional light intensity reconstruction on the holographic image, and obtaining a three-dimensional spatial light intensity distribution; processing the three-dimensional spatial light intensity distribution using a difference method to eliminate background noise interference and enhance the scattered light signal of the sperm flagellum; obtaining the node distribution of the sperm flagellum on the two-dimensional projection plane xy based on the three-dimensional spatial light intensity distribution processed by the difference method, and obtaining the position of the sperm flagellum on the z-axis one by one to achieve three-dimensional reconstruction of the sperm flagellum. The present invention reconstructs the morphology and position of the focused head, and simultaneously uses the difference method to enhance the flagellum signal and then searches for the three-dimensional coordinates of the modified sperm flagellum nodes, thereby achieving three-dimensional reconstruction of the sperm head and flagellum. The method is suitable for observing sperm from various animals and humans, and can obtain the dynamic three-dimensional position of multiple sperm cells in situ and without damage. The present invention can be widely used in the field of microscopic computational imaging.

The application discloses application of amino peptidase SapM in regulating virulence and motility of Xanthomonas campestris, and belongs to the technical field of biotechnology.The sapM gene function is researched by constructing a sapM gene deletion strain of Xanthomonas campestris.The research finds that knocking out the sapM gene (Delta sapM) significantly enhances the pathogenicity, extracellular polysaccharide (EPS) synthesis, amylase activity and motility of Xcc, while sapM overexpression inhibits the above-mentioned phenotypes.The flagellum morphology of the sapM mutant strain is further observed by transmission electron microscopy, and it is found that the flagellum length of the sapM mutant strain is significantly different from that of the wild type.It can be seen that the amino peptidase SapM is involved in negative regulation of virulence and motility of Xanthomonas campestris, and the application has great application value.

The invention provides a flagellum nanofiber vaccine and a preparation method and application thereof, the vaccine comprises flagellum, a cationic polymer and an antigen, the flagellum is negatively charged, the cationic polymer is self-assembled on the surface of the negatively charged flagellum through electrostatic interaction to form a nanofiber structure, and the antigen is self-assembled on the surface of the negatively charged flagellum. The antigen is coated on the surface of the nanofiber structure. The retention time of the nanofiber vaccine at an injection site is prolonged, and the uptake ability of dendritic cells and macrophages is improved. The immunogenicity of flagellum can significantly promote the maturation of dendritic cells and the polarization of macrophages, and induce the immune response of specific T cells and B cells. In melanoma mice expressing ovalbumin, vaccination with the vaccine carrying ovalbumin not only shows good tolerance, but also shows good inhibition effects on growth and metastasis of tumors in two modes of treatment and prevention.