38 results about "Bacterial enterotoxins" patented technology

The invention discloses a strain of Bifidobacterium breve capable of removing toxins in a body and a metagen of the Bifidobacterium breve, and belongs to the technical field of microbial application, the Bifidobacterium breve WZA-BB07 is separated from human excrement, and the biological preservation number of the Bifidobacterium breve WZA-BB07 is CCTCC (China Center for Type Culture Collection) NO: M20241530. The bacterial strain WZA-BB07 has a good effect of degrading endotoxin and enterotoxin, the bacterial strain and lactobacillus reuteri are subjected to mixed fermentation to prepare the postbiotics, bifidobacterium breve mainly improves intestinal flora balance and inhibits growth of harmful bacteria, the lactobacillus reuteri helps repair intestinal barriers through metabolites of the lactobacillus reuteri in the fermentation process, and the lactobacillus reuteri and lactobacillus reuteri are mixed to prepare the postbiotics. Metabolism and removal of toxins are enhanced; dendrobium officinale, honeysuckle and radix puerariae extracts are added into a fermentation culture medium, so that rich nutrition is provided for fermentation, the effects of resisting oxidation, resisting inflammation and promoting intestinal repair of medicinal and edible components are also exerted, and the detoxification capacity and the overall health effect of the postbiotic product are further improved.

The invention belongs to the field of biotechnology and medical configuration products, and provides a mucoprotein-tannic acid packaged probiotic preparation as well as a preparation method and application thereof. According to the preparation method disclosed by the invention, tannic acid and mucoprotein are encapsulated in escherichia coli Nissle 1917 and lactobacillus plantarum NC8, so that the mucoprotein-tannic acid encapsulated probiotic preparation is obtained. The probiotic microbial agent prepared by the invention has excellent resistance to severe environment of gastrointestinal tracts, and the adhesiveness of the probiotic microbial agent in intestinal tracts is enhanced, so that the colonization and growth of the probiotics in a mucous layer are enhanced. Meanwhile, bacterial enteritis, especially enteritis caused by enterotoxigenic escherichia coli (ETEC), can be effectively treated.

The invention discloses a mycoplasma hyopneumoniae multi-antigen fusion protein and a vaccine composition and application thereof, and belongs to the technical field of genetic engineering and vaccines. The fusion protein comprises an escherichia coli heat-labile enterotoxin LTB, a mycoplasma hyopneumoniae antigen protein P97R1, a mycoplasma hyopneumoniae lipoprotein 418 and a mycoplasma hyopneumoniae surface antigen protein P46 from the N terminal to the C terminal in the sequence. The vaccine composition comprises the fusion protein and an adjuvant acceptable in veterinary medicine. A vaccine prepared from the fusion protein has the advantages of higher pertinence and immunogenicity, the cell and humoral immune response level is remarkably improved, and meanwhile, the fusion protein is easy to purify and prepare and suitable for large-scale industrial production.

The present invention discloses a Bifidobacterium breve strain capable of clearing toxins in the body and its postbiotics, belonging to the technical field of microbial applications. The present invention isolates a Bifidobacterium breve strain ( Bifidobacterium breve ) WZA-BB07 from human feces, and its biological deposit number is: CCTCC NO: M20241530. The strain WZA-BB07 has good effects in degrading endotoxin and enterotoxin. The strain and Lactobacillus mucosae are mixed and fermented to prepare postbiotics. Bifidobacterium breve mainly improves the balance of intestinal flora and inhibits the growth of harmful bacteria. Lactobacillus mucosae helps repair the intestinal barrier through its metabolites during fermentation, enhancing the metabolism and clearance of toxins; extracts of Dendrobium officinale, Lonicera japonica, and Pueraria lobata are added to the fermentation medium, which not only provides rich nutrition for fermentation but also exerts the antioxidant, anti-inflammatory, and intestinal repair-promoting effects of ingredients with both medicinal and edible properties, further enhancing the detoxification ability and overall health effects of the postbiotic product.

The invention provides a staphylococcal enterotoxin B nano antibody and application thereof, and belongs to the technical field of nano antibodies. The staphylococcal enterotoxin B nano antibody disclosed by the invention comprises H9-VHH and H9-D7-VHH, and the staphylococcal enterotoxin B nano antibody disclosed by the invention comprises H9-VHH. The staphylococcal enterotoxin B (SEB) nano-antibody provided by the invention is provided with a Trx label, and a fusion expression plasmid of the SEB nano-antibody is constructed by utilizing a coding gene of the nano-antibody, so that the soluble expression of the nano-antibody in escherichia coli is realized. Based on the nano antibody, the invention also establishes a time-resolved fluorescence immunochromatography detection system aiming at SEB, and the system is sensitive, rapid and accurate in detection, strong in stability and high in specificity, and has a wide application prospect in the aspect of SEB detection.

The invention discloses a bacteriostatic composition which comprises a synergist and a bacteriostatic agent, the synergist is ethyl phenylacetate or a derivative thereof, and the bacteriostatic agent is selected from hydrogen peroxide, beta-lactam antibiotics, macrolide antibiotics and aminoglycoside antibiotics. The synergist disclosed by the invention is wide in synergistic effect spectrum range, and has a remarkable synergistic bacteriostatic effect when being combined with hydrogen peroxide, amoxicillin, ampicillin, benzylpenicillin potassium, erythromycin, azithromycin and amikacin; the antibacterial effect is weak when the compound is independently used, but the virulence of staphylococcus aureus can be remarkably reduced, the formation of hemolysin, staphylococcus flavin, enterotoxin and a biofilm can be inhibited, and meanwhile, the selective pressure on bacteria is favorably reduced due to the relatively low antibacterial activity, so that the occurrence of drug resistance is delayed; the method is suitable for various application scenes such as food processing industry.

The invention discloses an application of creatine in preparation of a medicine or a feed additive for treating or preventing pig pathogenic diarrhea, the medicine is creatine or is prepared into oral liquid, granules, tablets and powder by taking the creatine as an active ingredient and adding auxiliary materials, and the use dosage is that the content of the creatine is 30-300mg / kg of pig body weight; or the feed additive is directly added into the feed, and the adding amount is that the content of creatine accounts for 0.05-0.5% of the total weight of the pig feed. The medicine or the feed additive provided by the invention is high in safety and free from toxic and side effects, can effectively prevent and treat pathogenic diarrhea caused by infection of one or more pathogens of porcine epidemic diarrhea virus, porcine transmissible gastroenteritis virus, porcine rotavirus and enterotoxigenic escherichia coli, improves the intestinal morphological structure and the absorption function of diseased pigs, and improves the immunity of the pigs. The morbidity and mortality of piglets are reduced.

This invention belongs to the field of immunological testing and discloses nanobodies, antibody compositions, and their applications for detecting Staphylococcus aureus enterotoxin H. The invention successfully screened for Staphylococcus aureus enterotoxin H-specific antibodies and used a checkerboard titration method to identify capture antibodies, AntiSEH-Nb4, and detection antibodies, AntiSEH-Nb3. The resulting antibodies are effective for detecting food poisoning caused by non-classical enterotoxin H, providing a highly specific means of detecting Staphylococcus aureus enterotoxin H. This not only improves the accuracy and reliability of detection but also facilitates the rapid diagnosis and prevention of outbreaks of related foodborne diseases.

The invention discloses a preparation method and application of a hexavalent multi-epitope fusion protein of avian pathogenic Escherichia coli. The invention preferably selects antigenic epitopes of the curli fimbriae subunit CsgA, lipoprotein SlyB, maltose porin LamB, outer membrane protein PhoE, proteolytic enzyme activator NlpD and lipoprotein Pal main structural subunit of avian pathogenic Escherichia coli, and preferably connects with the heat-labile enterotoxin LTb fusion protein in series to construct an antigenic multi-epitope fusion protein of six proteins of avian pathogenic Escherichia coli. The antigenic multi-epitope fusion protein has a wide serotype coverage, is non-allergenic, has strong immunogenicity, and produces strong specific humoral immunity and cellular immune response after immunizing animals.

The invention belongs to the technical field of biosensors, and discloses a photoelectrochemical immunosensor based on a dendritic peptide tetramer as well as a preparation method and application of the photoelectrochemical immunosensor. The dendritic peptide tetramer is adopted to construct the photoelectrochemical immunosensor for the first time, and the method comprises the following steps: preparing an HsGDY / Cu2O photocathode, and sequentially anchoring an antibody probe and the dendritic peptide tetramer on the surface of the photocathode. Through specific binding of a target object and the antibody probe, a significant steric hindrance effect is generated on an electrode interface, interface charge transfer is hindered, photocurrent signal change is caused, and detection of the target object staphylococcus aureus enterotoxin A is realized. The photoelectrochemical immunosensor provided by the invention is simple, convenient and efficient in preparation process, has excellent food matrix biological pollution resistance, can effectively inhibit non-specific adsorption so as to significantly improve the sensitivity, specificity and accuracy of detection, is suitable for the field of food safety detection, and is suitable for market popularization and application.

The present invention discloses an mRNA encoding an anti-Staphylococcus aureus enterotoxin B antibody and an application thereof. The mRNA comprises an mRNA encoding a light chain of the anti-Staphylococcus aureus enterotoxin B antibody and an mRNA encoding a heavy chain of the anti-Staphylococcus aureus enterotoxin B antibody, wherein the optimized base sequences of the variable regions CDR1, CDR2 and CDR3 of the heavy chain are shown as SEQ ID NO.4, SEQ ID NO.5 and SEQ ID NO.6, respectively; and the optimized base sequences of the variable regions CDR1, CDR2 and CDR3 of the light chain are shown as SEQ ID NO.7, SEQ ID NO.8 and SEQ ID NO.9. The antibody can be used to neutralize SEB toxin and simultaneously prevent and treat Staphylococcus aureus infection.

The invention relates to the technical field of biological medicines, and particularly discloses a composition and application thereof in preparation of medicines for preventing and treating osteoporosis. The composition comprises enterotoxin c and a traditional Chinese medicine extract, wherein the weight ratio of the enterotoxin c to the traditional Chinese medicine extract is 1: (10-100). Researches show that the composition has the effect of treating or preventing osteoporosis; therefore, the compound has important application value when being used as an effective component for preparing the medicine with the effect of treating or preventing the osteoporosis.

This application discloses the application of creatine in the preparation of drugs or feed additives for the treatment or prevention of pathogenic diarrhea in pigs. The drugs are creatine or creatine as an active ingredient with added excipients to form oral liquids, granules, tablets, or powders. The dosage is 30–300 mg / kg of pig body weight; or it can be directly added to feed at a creatine content of 0.05%–0.5% of the total weight of the pig feed. The drugs or feed additives provided in this application are highly safe, have no toxic side effects, and can effectively prevent and treat pathogenic diarrhea caused by one or more pathogens, including porcine epidemic diarrhea virus, porcine transmissible gastroenteritis virus, porcine rotavirus, and enterotoxigenic Escherichia coli. They improve the intestinal morphology and absorption function of sick pigs and reduce the morbidity and mortality of piglets.

The application belongs to the technical field of biological gene engineering, and discloses a lactococcus lactis carrier oral vaccine for producing enterotoxigenic escherichia coli F18 pilus type and application. Four lactococcus lactis antigen surface display strains are prepared, and are mixed to perform oral immunization. The oral immunization mode is convenient to operate, avoids the stress reaction caused by injection immunization on animals, and greatly improves the immunization effect, so that the diarrhea caused by enterotoxigenic escherichia coli on piglets can be effectively prevented. 50 The application is an oral escherichia coli vaccine, and mouse immunization challenge experiment shows that all the mice can survive under the challenge dose of LD , and piglet immunization challenge experiment shows that the piglets can be 100% protected from diarrhea, which shows that the immunization group has effective mucosal immune protection ability.

The present invention discloses a non-pathogenic Escherichia coli isolate expressing only F4 fimbriae adhesin and its application. The growth rate of the strain of the present invention is similar to that of the standard reference strain C83902 of F4ac+ enterotoxigenic Escherichia coli, and it exhibits good adhesion to the small intestinal epithelial cells of piglets in vitro experiments. Immunizing mice with the fimbriae adhesin extract extracted from the isolate or immunizing piglets with the inactivated vaccine prepared based on the isolate can induce the production of high-titer anti-FaeG antibodies, and the obtained immune piglet serum significantly inhibits the adhesion of the F4ac+ETEC domestic reference strain C83902 strain to IPEC‑J2 cells. The non-pathogenic Escherichia coli isolate is expected to become a candidate live vaccine strain for preventing diarrhea in piglets caused by infection with enterotoxigenic Escherichia coli expressing F4 fimbriae adhesin.

The application discloses a recombinant M13 bacteriophage, a K88-targeting antibacterial preparation containing the bacteriophage and application of the antibacterial preparation, and belongs to the field of biotechnology and veterinary medicine. The antibacterial preparation contains the recombinant M13 bacteriophage rM13; a K88-targeting element is displayed on the tail fiber pIII protein of the recombinant M13 bacteriophage, and the K88-targeting element is a nanobody NBK88 with an amino acid sequence shown in SEQ ID NO:1. The engineering in the application enables the rM13 to specifically recognize, invade and lyse enterotoxigenic Escherichia coli expressing K88 fimbriae, so that the host range of the wild-type M13 is accurately guided to pathogenic bacteria. The application also provides use of the preparation in preparation of a medicine for preventing or treating ETEC infection, and a dosage form of the medicine is preferably a freeze-dried preparation or an enteric preparation capable of releasing in the intestinal tract. The preparation provided by the application has the advantages of high targeting, self-proliferation, non-damage to intestinal microecology and overcoming of bacterial drug resistance.

The present invention provides an enterotoxin C Raman sensing analysis method based on Au-Ag Janus@Au NPs, belonging to the technical field of Raman spectroscopy analysis. The present invention first synthesizes Au-Ag Janus NPs by guiding the directional growth of Ag islands on Au cores through 2-mercaptobenzimidazole-5-carboxylic acid (MBIA), and the ligand MBIA also acts as a Raman beacon molecule. By regulating the pH, an Au layer is grown on the surface of Au-Ag Janus NPs to obtain Au-Ag Janus@Au NPs, which have a stronger and more stable SERS signal. With MBIA 1278cm ‑1 Using the SERS signal at the site as the detection signal, a Raman sensor for detecting enterotoxin C was designed. The Raman sensor has the advantages of good sensitivity, high accuracy, strong stability and strong anti-interference ability.

A broadly protective Shigella-ETEC vaccine includes components to cover multiple Shigella species and serotypes as well as multiple different colonization factors of ETEC. ETEC colonization factors CS2 and CS3 are among the most prevalent CFs found on ETEC isolates associated with diarrhea. These two factors are important components of a vaccine that can confer broad protection against ETEC. High level expression of these heterologous antigens in Shigella live vectors results in stronger immune responses. This specification describes the genetic engineering of DNA sequences encoding upstream sequences, including promoter and ribosome binding sites, that results in increased expression of CS2 and CS3 in Shigella live vectors and that leads to stronger immune responses when used as a vaccine in animal models.

The invention discloses mRNA (messenger Ribonucleic Acid) for coding an anti-staphylococcus aureus enterotoxin B antibody and application of the mRNA. The mRNA comprises a light chain mRNA for coding the anti-staphylococcus aureus enterotoxin B antibody and a heavy chain mRNA for coding the anti-staphylococcus aureus enterotoxin B antibody, and optimized base sequences of variable regions CDR1, CDR2 and CDR3 of the heavy chain are respectively shown as SEQ ID NO.4, SEQ ID NO.5 and SEQ ID NO.6; the optimized base sequences of the variable regions CDR1, CDR2 and CDR3 of the light chain are as shown in SEQ ID NO. 7, SEQ ID NO. 8 and SEQ ID NO. 9; the antibody can be used for neutralizing SEB toxin and preventing and treating staphylococcus aureus infection at the same time.

The invention provides a composition containing enterotoxin C. The composition comprises the following components: 5-100 ng / mL of enterotoxin C; 0.1 to 5 mg / mL of protein, wherein the protein is selected from whey protein, soy protein isolate or collagen; the concentration of the polypeptide is 0.05 to 3 mg / mL, and the polypeptide is collagen peptide or whey peptide with the molecular weight of 500 to 5000 Da; 1.0 to 8.0 mg / mL of an amino acid mixture, wherein the amino acid mixture comprises 18 essential and non-essential amino acids. The enterotoxin C-containing composition disclosed by the invention realizes remarkable breakthrough in the aspects of stability, targeting property and multifunctionality through a multi-component synergistic effect and technical innovation.

The invention relates to the field of biological medicine and immunology, in particular to preparation and application of an anti-staphylococcus aureus enterotoxin B antibody. A heavy chain variable region of the antibody SEB-A8 provided by the invention comprises CDR sequences as shown in SEQ ID NO: 1-3, a light chain variable region of the antibody SEB-A8 comprises CDR sequences as shown in SEQ ID NO: 9-11, and the antibody SEB-A8 has important application value in treatment, prevention or diagnosis of staphylococcus aureus infection. Experimental data show that the antibody can effectively neutralize the superantigen activity of SEB and significantly improve the survival rate of MRSA infected mice, has a dose-dependent protection effect, can be used as a non-antibiotic treatment strategy, is used for treatment of methicillin-resistant staphylococcus aureus infection, has great significance in controlling development of bacterial drug resistance, and has a broad application prospect. And a new research direction is provided for clinical anti-infection treatment.

The present invention discloses an application of curcumin-mediated photodynamic degradation of Staphylococcus aureus enterotoxin. The present invention effectively proves through experiments that water-soluble curcumin-mediated photodynamic can effectively reduce the enterotoxin content and its immunological activity. The present invention also provides a method for effectively inactivating Staphylococcus aureus and its enterotoxin. This method has high safety, low equipment requirements, simple operation, causes non-specific damage to the bacteria, is not prone to generating resistance, is non-toxic, has low cost, and can effectively control the risk of food poisoning caused by Staphylococcus aureus and its enterotoxin. The water-soluble curcumin-mediated photodynamic technology provided by the present invention has the potential for application in food processing.

The present application relates to a kind of antigen binding protein pair specifically binding enterotoxin SEC and its application.The antigen binding protein pair of the present application includes the first antigen binding protein 16E12 combined with enterotoxin SEC and the second antigen binding protein 9B7 combined with enterotoxin SEC combined with the first antigen binding protein 16E12.The antigen binding protein of the present application has unique variable region sequence, the minimum detection limit for enterotoxin SEC is 0.1ng / mL, and there is no cross reaction for enterotoxin SEA, SEB, SED, SEE and common microbial toxin;The antigen binding protein sequence of the present application is clear, can effectively avoid gene mutation, the batch difference of antigen binding protein is small, quality is stable, structure is complete, it is helpful to the development of stable immune analysis detection method.

The invention provides a photoelectrochemical aptamer sensor as well as a preparation method and application thereof, and relates to the technical field of biosensors, according to the photoelectrochemical aptamer sensor provided by the invention, a heterostructure of narrow-band-gap CdIn2S4 and WO3 is constructed, so that the prepared WO3 / CdIn2S4 composite material shows excellent photoelectrochemical signal response, and the photoelectrochemical aptamer sensor can be applied to the field of biosensors. According to the present invention, by combining the specific recognition effect of the aptamer, the sensitive analysis of the target object staphylococcal enterotoxin B (SEB) can be achieved, the sensor has characteristics of simple operation and strong anti-interference, the detection range is 1.0 * 10 <-17 >-1.0 * 10 <-12 > mol / L, the detection limit is as low as 1.26 * 10 <-18 > mol / L, and the sensor can be successfully used for the high-selectivity and rapid detection of the SEB in the water sample.

The invention discloses a B cell conservative epitope peptide of enterotoxigenic Escherichia coli V-type secretion system effect protein EatA and application thereof, and particularly relates to application in ETEC specific antibody diagnosis. The B cell conservative epitope peptide disclosed by the invention can be functionally displayed and expressed on the surface of an inert carrier S9H thallus, PT8 is displayed and expressed on the surface of the S9H thallus, and an agglutination test directly mediated by the PT8 and specifically recognized by an antibody is established, so that only ETEC pathogen infectious antibodies are specifically recognized, other pathogenic escherichia coli can be identified and diagnosed, and the B cell conservative epitope peptide has a good application prospect. And no cross reaction with serum antibodies of other infectious diseases exists. According to the method, the specific serum antibody can be detected 7 days after a Balb / c mouse is infected by the ETEC strain H10407. The diagnosis method is high in specificity, good in sensitivity, convenient to operate and intuitive in result judgment, and is expected to become a technical means for visual on-site accurate and convenient diagnosis of ETEC infection.

The invention relates to an antigen binding protein pair specifically binding to enterotoxin SEC and application of the antigen binding protein pair. The antigen-binding protein pair of the present invention comprises a first antigen-binding protein 16E12 that binds to enterotoxin SEC and a second antigen-binding protein 9B7 that binds to enterotoxin SEC to which the first antigen-binding protein 16E12 is bound. The antigen binding protein disclosed by the invention has a unique variable region sequence, the lowest detection limit of the antigen binding protein to enterotoxin SEC is 0.1 ng / mL, and the antigen binding protein has no cross reaction to enterotoxins SEA, SEB, SED and SEE and common microbial toxins; the antigen binding protein disclosed by the invention is clear in sequence, capable of effectively avoiding gene mutation, small in batch difference, stable in quality and complete in structure, and contributes to the development of stable immunoassay detection methods.

This invention relates to the fields of biomedicine and immunology, and particularly to the preparation and application of an anti-Staphylococcal enterotoxin B antibody. The antibody provided by this invention has a SEB-A8 heavy chain variable region containing CDR sequences as shown in SEQ ID NO:1-3, and a light chain variable region containing CDR sequences as shown in SEQ ID NO:9-11. It has significant application value in the treatment, prevention, and diagnosis of Staphylococcus aureus infections. Experimental data show that this antibody can effectively neutralize the superantigen activity of SEB, significantly improve the survival rate of MRSA-infected mice, and exhibit a dose-dependent protective effect. It can be used as a "non-antibiotic" treatment strategy for the treatment of methicillin-resistant Staphylococcus aureus infections, which is of great significance in controlling the development of bacterial resistance and provides a new research direction for clinical anti-infective therapy.

The invention provides an antibody SEC55, a fusion protein SEC55-vHRP, a preparation method and an application. The fusion protein comprises an IgG antibody signal peptide, a hemagglutinin tag, the antibody SEC55, a connecting peptide, horse radish peroxidase and a histidine tag. The fusion protein can be used for detecting staphylococcus aureus enterotoxin C in food. The fusion protein SEC55-vHRP is provided with a horse radish peroxidase label, so that secondary antibody incubation is not needed, subsequent chromogenic reaction can be directly carried out after primary incubation is finished, the detection time is shortened, and the fusion protein SEC55-vHRP has a wide application prospect.

A broadly protective Shigella-ETEC vaccine includes components to cover multiple Shigella species and serotypes as well as multiple different colonization factors of ETEC. ETEC colonization factors CS2 and CS3 are among the most prevalent CFs found on ETEC isolates associated with diarrhea. These two factors are important components of a vaccine that can confer broad protection against ETEC. High level expression of these heterologous antigens in Shigella live vectors results in stronger immune responses. This specification describes the genetic engineering of DNA sequences encoding upstream sequences, including promoter and ribosome binding sites, that results in increased expression of CS2 and CS3 in Shigella live vectors and that leads to stronger immune responses when used as a vaccine in animal models.