17 results about "Campylobacter jejuni" patented technology

The invention belongs to the technical field of microbial genetic engineering, and particularly relates to an alpha-2, 3-sialyltransferase mutant and application thereof. The a-2, 3-sialyltransferase mutants V175N, P198A, G173D, D174Q, F196K and A315H are obtained by performing site-specific mutagenesis on six amino acids in an a-2, 3-sialyltransferase amino acid sequence coded by a gene derived from Campylobacter jejuni (OH4384), the yield of 3 '-sialyllactose is remarkably increased by single-point mutagenesis of the V175N, the yield of 3'-sialyllactose is remarkably increased by single-point mutagenesis of the V175N, the yield of 3 '-sialyllactose is remarkably increased by single-point mutagenesis of the P198A, the G173D, the D174Q, the F196K and the A315H, the optimal recombinant microbial strain 3 '-SL-09 (V175N / P198A / D174Q) is obtained through combination of multiple mutation sites, the yield can reach 5.91 g / L, the bottleneck problem of low catalytic efficiency of sialyltransferase is effectively solved, and an enzyme element with excellent performance is provided for high-efficiency and low-cost biological manufacturing of 3'-SL.

The invention relates to the technical field of microorganisms, in particular to a lactobacillus plantarum strain LM2 and application of the lactobacillus plantarum strain LM2. The strain has relatively high GABA (gamma-aminobutyric acid) production capacity and nitrite degradation capacity, has a bacteriostatic effect on intestinal pathogens such as staphylococcus aureus, salmonella enteritidis, listeria monocytogenes and campylobacter jejuni, has a good bacteriostatic function, also has good acid resistance and cholate resistance, and can be used for preparing a bacterial strain for treating intestinal diseases. The strain can well survive in artificial intestinal juice and artificial gastric juice; in order to increase the yield of GABA, the accelerant capable of remarkably promoting the growth of the strain LM2 is obtained by researching the accelerant, and the highest survival rate of the freeze-dried powder prepared by optimizing the accelerant and the freeze-dried powder can reach 99% or above, the nitrite degradation rate can reach 99% or above, the yield of GABA is increased to 3.0 g / L or above, and the freeze-dried powder is bacterial powder capable of being widely applied.

This invention discloses a fermented microbial preparation for inhibiting Campylobacter jejuni in calves, its preparation method, and its application. The fermented microbial preparation is a co-fermentation product of a mixture of Lygodium japonicum decoction and liquid culture medium, inoculated with Lactobacillus paracasei; the Lactobacillus paracasei is... Lacticaseibacillus paracasei KQNIU. Comparative experiments in this invention revealed that, compared to other types of traditional Chinese medicine, the inhibitory effect of fermented Lygodium japonicum on Campylobacter jejuni is significantly higher than that of other types of traditional Chinese medicine. Furthermore, the co-fermentation of the traditional Chinese medicine Lygodium japonicum and the probiotic Lactobacillus paracasei KQNIU achieves a synergistic effect between the two, overcoming the problem of limited efficacy when used alone.

An antimicrobial peptide having an amino acid sequence selected from SEQ ID NOs: 2-12 is provided. The antimicrobial peptide has antimicrobial activity against Gram-negative bacteria, Campylobacter jejuni, Escherichia coli, Salmonella enterica subsp. enterica serovar typhimurium, Salmonella enterica subsp. enterica serovar choleraesuis, Klebsiella pneumonica, and / or Enterobacter cloacae. A composition, pharmaceutical composition, food additive, cosmetic composition, or hygine product having an antimicrobial peptide including an amino acid sequence selected from SEQ ID NOs: 2-12 is also provided. A method of treating an infectious disease caused by bacteria including a step of administering a pharmaceutical composition having the antimicrobial peptide as an active ingredient is also provided.

The invention discloses a dual digital PCR (polymerase chain reaction) detection method for monkey campylobacter jejuni and monkey enterocolitis yersinia, and relates to the technical field of microbiological detection, the detection method comprises the following specific steps: multi-source heterogeneous data collection: collecting monkey feces and intestinal tissue samples, extracting genome DNA (deoxyribonucleic acid) by using a phenol-chloroform method, detecting the concentration and purity of DNA, and detecting the concentration and purity of the DNA; after reaching the standard, storing at-20 DEG C for later use; according to the method, high-sensitivity and specific detection on the two pathogenic bacteria is realized through a combination of well-designed primers and probes, according to the method, a gyrA gene conserved region of monkey campylobacter jejuni CJ and a POL gene conserved region of monkey yersinia enterocolitica YE are used as detection targets, and specific fragments of 249bp and 182bp are amplified respectively; the method effectively avoids interference of non-specific amplification, can simultaneously detect two pathogenic bacteria in a single reaction system through a dual digital PCR technology, accurately calculates target gene copy number concentration through a Poisson distribution formula, and improves detection accuracy and reliability.

The present application relates to the field of microbial technology, in particular to bacillus subtilis BS-1 and its application in water buffalo silage feed, the strain BS-1 of the present application has good bacteriostatic activity on escherichia coli, salmonella and streptococcus uberis, after mixing and fermenting according to a specific proportion with orange peel and cassava residue, the bacteriostatic spectrum of the obtained silage feed is significantly enhanced, which can simultaneously inhibit escherichia coli, campylobacter jejuni, salmonella, streptococcus uberis, staphylococcus aureus and streptococcus agalactiae that cause diarrhea and mastitis. In the feed, after mixing 60%-75% of orange peel and 25%-40% of cassava residue, the crude protein content of the fermentation product is significantly improved, and the fiber content is reduced. Feeding test shows that the feed can significantly improve the milk yield and milk quality of lactating water buffalo, and effectively alleviate diarrhea. The present application provides a safe, efficient and nutritious silage feed with disease prevention function.

The present application relates to the field of agricultural husbandry and veterinary technology, in particular to a protease-resistant antibacterial peptide FR and application thereof. The present application provides a protease-resistant antibacterial peptide FR, and the amino acid sequence of the antibacterial peptide FR is shown as SEQ ID NO. 1. The results of the specific implementation of the present application show that the protease-resistant antibacterial peptide FR provided by the present application has the activity of resisting gram-negative bacteria (Escherichia coli, Shigella flexneri, Salmonella and Campylobacter jejuni, etc.), has low hemolytic activity, can resist the cleavage of high-concentration protease, and has very good application prospect. In summary, the antibacterial peptide FR provided by the present application has the advantages of resisting gastrointestinal environment, resisting high salt and resisting protease cleavage, can realize the killing effect on gram-negative bacteria in the presence of enzymes and salt ions, and has the characteristics of low hemolytic activity, thereby providing a new way for the development of antibiotic substitutes.

The present invention discloses species-specific molecular targets yclQ, crRNA, CRISPR / Cas12a systems, detection methods, and kits for detecting Campylobacter jejuni. The nucleotide sequence of the target yclQ is shown in SEQ ID NO.1. Based on the target yclQ, the present invention has developed three detection kits for Campylobacter jejuni, namely, a kit based on the RAA / PCR-CRISPR / Cas12a system, a chimeric fluorescence qPCR detection kit, and a probe-based qPCR detection kit. The above three kits can all achieve high detection sensitivity for detecting Campylobacter jejuni, among which the detection sensitivity of the first kit is 5.3×10 0 The detection method of the present invention has the characteristics of strong specificity, high sensitivity, fast detection speed, etc., and can be applied to the field of food safety.

To provide compositions and methods for detecting gastrointestinal pathogens.SOLUTION: Compositions, methods, kits, and uses are provided for detecting the presence of Salmonella, Shigella, Campylobacter, and Shigatoxigenic Eschelichia coli (STEC) in samples. In some embodiments, the compositions, methods, kits, and uses comprise one or more oligonucleotides or the use of one or more oligonucleotides. In some embodiments, the method is carried out as a multiplex assay with separate primers / probes for C.jejuni and C.coli. Some of the oligonucleotides contain inosine and / or contain 5-methylcytosine substituted nucleotides. Described is the use of cyclodextrin and / or Polysorbate 20 in the amplification reactions.SELECTED DRAWING: None

The invention relates to a food product for animals which can be used as a prophylactic measure to reduce the number of Campylobacter jejuni in hosts like poultry or swine.More specifically the invention is a food supplement comprising neohesperidin dihydrochalcone (NHDC) and peppermint oil (PMO).The invention also pertains to a feed comprising such a food supplement as well as to its use to reduce campylobacter carriage by poultry or swine and to a method of reducing the risk of Campylobacter spp. infection in humans.

The invention relates to an integrated campylobacter jejuni detection device and a method thereof.The integrated campylobacter jejuni detection device comprises a base, a first moving assembly is arranged on the base, a clamping assembly used for containing a transfer pipette is arranged on the first moving assembly, and a pressing assembly is arranged on the clamping assembly; the base is further provided with a second moving assembly and a plurality of placing seats used for placing vessels, the second moving assembly is provided with a camera shooting assembly used for observing changes of campylobacter jejuni in the vessels, and the campylobacter jejuni can be automatically moved into the observation vessels from the culture tank; meanwhile, a culture solution containing bacteria and remaining at the outlet end of the pipette can be prevented from dripping on the outer side in the transfer-in process.

The invention discloses a campylobacter jejuni liquid-phase probe targeted capturing and library building method and a kit thereof, and belongs to the technical field of germ detection. Specific probe enrichment, magnetic bead purification and high-throughput sequencing are combined, and the problems that in the prior art, low-load detection is difficult, information is incomplete, and operation is tedious are solved. Aiming at the characteristics of wide food-borne transmission, multiple low-load samples and strong complex matrix interference of campylobacter jejuni, low-load accurate detection, whole-genome information analysis and high-throughput standardized operation are realized through a liquid-phase probe targeted capture technology; the method is suitable for large-scale sample detection in the fields of food safety detection, clinical diagnosis, public health research and the like.

This invention discloses a monoclonal antibody for detecting the surface protein SapA of Campylobacter fetus and its application. The monoclonal antibodies are named 4F6 and 7B3, and the amino acid sequences of the heavy and light chain variable regions of these two antibodies are disclosed. The monoclonal antibody prepared by this invention can specifically recognize the surface protein SapA of Campylobacter fetus. The prepared monoclonal antibody has good specificity, showing no cross-reactivity with non-Camplybacteria such as standard Escherichia coli, Salmonella, Listeria, Klebsiella pneumoniae, Staphylococcus aureus, and Streptococcus, and also with Campylobacter jejuni and Campylobacter coli. The test strip prepared by combining the monoclonal antibody of this invention with colloidal gold can achieve rapid on-site detection of Campylobacter fetus with a low detection limit and high sensitivity, successfully developing an immunological method for the specific detection of Campylobacter fetus.

The invention discloses a method for detecting campylobacter jejuni cell swelling toxin CdtB in food, and provides application of a campylobacter jejuni cell swelling lethal toxin CdtB monoclonal antibody to detection of campylobacter jejuni in food for the first time. The invention aims to establish the detection kit and the detection method based on the campylobacter jejuni cell swelling toxin CdtB monoclonal antibody, and the detection kit and the detection method have relatively strong specificity and sensitivity. The CdtB monoclonal antibody prepared by the invention can be combined with CdtB protein secreted by campylobacter jejuni in food, so that the detection of the campylobacter jejuni is realized. The detection speed is high, semi-quantitative detection can be achieved, the detection sensitivity is high, and the lowest CdtB mass of 0.01 microgram can be detected.

The present invention belongs to the field of food safety and poultry processing technology, and specifically relates to an antibacterial composition for inhibiting bacteria in the VBNC state, and its application and product. The present invention provides an antibacterial composition, which is composed of carvacrol, diallyl sulfide and aluminum oxide nanoparticles. The antibacterial composition significantly improves the inhibitory effect on VBNC Campylobacter jejuni through synergistic action, not only enhancing the antibacterial activity but also effectively reducing the risk of drug resistance. The present invention calculates the optimal ratio of antibacterial agents through a dosage optimization method based on a mathematical model, maximizes the antibacterial effect and ensures its stability in different processing environments. The present invention solves the problem of the inability to inhibit VBNC bacteria in the prior art and ensures food safety. In addition, the combination of natural plant ingredients and non-toxic nanoparticles is both safe and environmentally friendly, suitable for multiple fields such as poultry processing, and has broad application prospects.

The use of Campylobacter jejuni and its toxin in the preparation of drugs for preventing, diagnosing, predicting, treating colorectal cancer and extra-intestinal tumor metastasis. Campylobacter, especially Campylobacter jejuni and toxin CDT, can be used as a marker to distinguish whether a colorectal cancer patient has metastasis. Experiments have proved that Campylobacter jejuni has the ability to promote metastasis and invasion. Campylobacter jejuni promotes the invasion and metastasis of colon cancer cells by CDT protein and the up-regulated JAK2 / STAT3 / MMP9 signaling pathway activated by CDT protein. When the process is blocked, the tumor metastasis-promoting ability of Campylobacter jejuni is weakened or lost. Campylobacter jejuni also promotes the metastasis of extra-intestinal tumors. Based on drugs or agents that can block this process, the metastasis of colorectal cancer cells and extra-intestinal tumors can be prevented and inhibited. Based on Campylobacter jejuni and its toxin, corresponding reagents or methods are developed for diagnosing or predicting the metastasis of colorectal cancer and extra-intestinal tumors. Through the marker provided in the present application, it is expected to inhibit tumor metastasis and prolong the survival of patients.

The invention discloses a novel cyclic antibacterial peptide with a broad-spectrum antibacterial effect and application of the novel cyclic antibacterial peptide, the obtained novel antibacterial peptide is named as N1-7567, and the novel cyclic antibacterial peptide belongs to the technical field of antibacterial peptides. The amino acid sequence of the novel antibacterial peptide N1-7567 is AFLKRFSCRLIRAGKYLSCLLQPAA, and the C at the 8 site and the C at the 19 site are S-S. The invention also discloses a preparation method of the novel antibacterial peptide N1-7567. The obtained antibacterial peptide has a broad-spectrum antibacterial effect, the minimum inhibitory concentration (MIC) of the antibacterial peptide N1-7567 to campylobacter jejuni 81-176 is 22.13 mu M, and the novel antibacterial peptide is expected to become a novel prevention and control product for campylobacter jejuni.