21 results about "Pilus" patented technology

The invention discloses a recombinant M13 bacteriophage, a K88 targeting antibacterial preparation containing the bacteriophage and application of the K88 targeting antibacterial preparation, and belongs to the field of biotechnology and veterinary medicine. The antibacterial preparation comprises a recombinant M13 bacteriophage rM13; a K88 targeting element is displayed on a tail filament pIII protein of the recombinant M13 bacteriophage, and the K88 targeting element is a nano antibody NBK88 of which the amino acid sequence is as shown in SEQ ID NO: 1. Through engineering modification, the rM13 can specifically recognize, infect and split enterotoxigenic escherichia coli expressing K88 fimbriae, so that the host range of the wild type M13 is accurately guided to pathogenic bacteria. The invention also provides application of the preparation in preparation of medicines for preventing or treating ETEC infection, and the dosage form of the preparation is preferably a freeze-dried preparation or an enteric-coated preparation capable of being released in a targeted intestinal tract. The preparation provided by the invention has the remarkable advantages of strong targeting property, self-proliferation, no damage to intestinal microecology and capability of overcoming bacterial drug resistance.

The invention relates to molecular glue for forming fimbriae related protein based on SpaA isopeptide bonds of Vinci bacteria. The invention also relates to a nanoparticle vaccine composition formed by the molecular glue, and the immunogen is covalently displayed on the surface of the nanoparticle by the molecular glue.

Provided herein are achromosomal dynamic active systems comprising a Type 1 pilus (TIP) and methods of making and using the same.

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 application belongs to the field of microbiology and veterinary microbiological technology, and relates to a strain of enterotoxigenic Escherichia coli carrying F5 and F41 fimbriae and application thereof. The strain is isolated from a fecal sample of a diarrheal calf, and is confirmed to be enterotoxigenic Escherichia coli carrying F5 fimbriae-related genes, F41 fimbriae-related genes and ST enterotoxin estA gene through isolation and culture, morphological identification, biochemical identification, fimbriae gene and virulence gene PCR detection and whole genome sequencing analysis. The strain has been preserved in the China General Microbiological Culture Collection Center on June 13, 2022, and the preservation number is CGMCC No. 25077. Pathogenicity tests show that the strain has strong virulence and can stably establish an animal infection model. Drug sensitivity tests show that the strain has a specific sensitivity spectrum to a variety of antibacterial drugs. The strain can be used for animal infection model establishment, antibacterial drug evaluation, calf diarrhea pathogenesis research, prevention and control technology research, and can also be used for preparing biological agents for preventing or diagnosing calf diarrhea.

To provide compositions and methods for preventing, inhibiting, disrupting, or treating polymicrobial biofilms.SOLUTION: For example, methods are provided for one or more of the following: preventing, inhibiting, disrupting, dispersing, or treating invitro and / or invivo a polymicrobial biofilm comprising Haemophilus bacteria in a subject in need thereof. The method comprises or consists essentially of or yet further consists of contacting a multi-microbial biofilm with (i) an anti-DNA binding and bending protein (DNABII) antibody or a biologically active fragment thereof and (ii) an anti-type IV pilin (T4P) majority subunit (PII A) antibody or a biologically active fragment thereof.SELECTED DRAWING: None

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.

This invention discloses a method and application for detecting F17 Escherichia coli. Using the fimbrial virulence gene ctg_04543 or ctg_04549 of F17 E. coli as a target, a fluorescent quantitative probe is designed based on the nucleotide sequence. Using F17 E. coli genomic DNA as a template, the F17 fimbrial gene ctg_04543 or ctg_04549 is detected by fluorescent quantitative PCR. Based on the fitted standard curve, F17 E. coli in the sample can be quantitatively detected. The F17 E. coli detection method provided by this invention is simple, rapid, quantitative, highly sensitive, and highly specific. It can achieve quantitative detection of F17 E. coli within 2-3 hours, meeting the detection needs of various situations such as laboratory research and animal pathogen diagnosis, and has broad application prospects and extremely high market implementation potential.

Method for detecting pathogenic strains of Escherichia coli expressing the f17g gene of the F17 fimbria gene. The invention relates to a detection method based on the amplification of the genomic DNA of the pathogenic strain using LAMP technology with specific primers at a temperature of 62°C. This reaction is carried out with the Cas12a enzyme, previously activated with a guide RNA specific to the F17g gene. This method allows for the rapid detection of pathogenic strains with rudimentary equipment and can be associated with a rapid diagnostic device in the field.

The invention discloses application of luteoloside in preparation of a medicine for inhibiting adhesion and invasion of uropathogenic escherichia coli, and belongs to the technical field of medical biology. The technical problem to be solved is to provide new application of the luteoloside, and research finds that although the luteoloside does not have a direct bacteriostatic effect, the luteoloside significantly inhibits UPEC movement and biofilm formation, destroys a pilus / flagellum ultrastructure, and down-regulates virulence genes (fimH, papG and fliC). The luteoloside can reduce UPEC adhesion and invasion, restore the barrier function and reduce the level of IL-6 and TNF-alpha. Therefore, the luteoloside is used as a host-oriented antivirulence natural product, the pathogenic effect of the luteoloside is effectively relieved by inhibiting UPEC virulence and regulating CAV1 related epithelial process, and transformation application potential is provided for management of urinary tract infection.

The invention relates to the technical field of bioengineering and protein engineering, in particular to an escherichia coli genetically engineered bacterium and a high-throughput screening method of an enzyme. According to the high-throughput screening method of the enzyme, the enzyme is displayed on the surface of escherichia coli, and the surface display efficiency of the enzyme is remarkably improved by optimizing an escherichia coli curli fimbriae system, so that the screening efficiency of the enzyme is improved, the screening steps are reduced, and the screening cost is reduced. The method solves the problems of need of cell disruption, complex operation, easy reduction of protein activity and low screening efficiency of a traditional screening method in an enzyme directed evolution process, and has the advantages of no need of cell disruption, simple and easy operation, high flux, specific and accurate enzyme activity determination, wide enzyme activity detection range, high screening efficiency and the like; good application prospects are realized.

The invention discloses an attenuated synergistic host chassis capable of being widely applied to production of pseudomonas aeruginosa bacteriophage as well as a construction method and application of the attenuated synergistic host chassis, and belongs to the technical field of microorganisms. According to 68 bacteriophages separated from the pseudomonas aeruginosa type strain PAO1, the comprehensive host range of the 68 bacteriophages can cover 97% (238 / 245) of 245 pseudomonas aeruginosa separated from multiple hospitals, and the target of amplifying clinical pseudomonas aeruginosa bacteriophages by a single host bacterium is achieved. By knocking out a phage resistance system, a prophage, a virulence factor effect protein and an antibiotic resistance related gene in the PAO1, the yield of the PAO1 phage is increased, and pollution of most secretory prophages, virulence factors and antibiotic inactivating enzymes to the phage is removed from the source. Key virulence factors such as O antigens, fimbriae and core oligosaccharides are further knocked out to synthesize related genes, pollution of the O antigens, the fimbriae and the core oligosaccharides is reduced, lipopolysaccharide is greatly truncated, and the purification problem is solved.

The application discloses construction and application of Escherichia coli with high L-threonine yield, and belongs to the field of genetic engineering and fermentation engineering. In the genome of Escherichia coli TWF001, the pilus synthesis gene clusters Ycb, Yad, Yde, Yeh, Yqi, Yra, Yfc, Type1, Yhc and Sfm are knocked out to obtain mutant TWK021. The L-threonine yield of the TWK021 strain in a fermentation medium is 15.75 g / L, which is increased by 32.4% compared to the TWF001 yield, and the L-threonine yield of 62.7 g / L is obtained in a fed-batch fermentation. The application constructs a stable Escherichia coli with high L-threonine yield, and the plasmid does not need to be maintained by antibiotics in the whole fermentation process, and a new strategy for increasing the L-threonine yield of Escherichia coli is provided.

The disclosure provides an engineered escherichia coli and application thereof, and relates to the technical field of biotechnology.The engineered bacteria provided by the disclosure knock out the natural type I pilus, can effectively reduce the non-specific targeting adhesion rate of the engineered bacteria without changing the growth condition and morphology of the engineered bacteria, can realize flexible targeting of various target cells by replacing the single-domain antibody sequence of the extracellular artificially synthesized adhesin (intimin or YeeJ), and has the potential to become a precision treatment toolkit.The antigen-antibody combination can be visualized at the cell level, and the antigen-antibody combination is convenient and time-saving, and provides a powerful tool for evaluating the antibody affinity in the antibody screening work.The engineered bacteria provided by the disclosure can specifically colonize inside tumors, have a certain tumor growth inhibition effect, and have high biological safety.Further, on the basis of targeted adhesion, the cytotoxic molecules are increased, can accelerate the induction of tumor cell apoptosis, and have a significant anticancer effect.

The application discloses a broad-spectrum attenuated and synergistic host chassis for production of pseudomonas aeruginosa phage, a construction method and application thereof, and belongs to the technical field of microorganisms. 68 phages isolated from a model strain of Pseudomonas aeruginosa PAO1 can cover 97% (238 / 245) of 245 Pseudomonas aeruginosa strains isolated from multiple hospitals, and the target of amplifying clinical Pseudomonas aeruginosa phage by a single host strain is achieved. By knocking out phage resistance systems, prophages, virulence factor effector proteins and antibiotic resistance related genes in PAO1, the production of PAO1 phage is improved, and most of the secreted prophages, virulence factors and antibiotic inactivation enzymes are removed from the source to pollute the phage. Further, key virulence factor synthesis related genes such as O antigen, pilus and core oligosaccharide are knocked out, the pollution of O antigen, pilus and core oligosaccharide is reduced, the lipopolysaccharide is greatly truncated, and the problem of purification is solved.

The invention discloses a B cell epitope peptide hybridoma cell strain on migratory locust zona pellucida membrane protein LmPio and a monoclonal antibody and application thereof, LH10 is inserted into a passenger-carrying structural domain of a salmonella V-type secretion system MisL and is introduced into escherichia coli DH5alpha, the LH10 is displayed and expressed on the surface of DH5alpha thallus, the hybridoma cell strain is used as an immunogen, and the hybridoma cell strain can be used for detecting the B cell epitope peptide on the migratory locust zona pellucida membrane protein LmPio. After a mouse is immunized, splenocytes of the mouse are fused with Sp2 / 0 to obtain the LH10-resistant mAb hybridoma cell. The LH10 is inserted into a salmonella peg pilus operon and is introduced into an inert carrier bacterium S9H, the LH10 is subjected to functional display expression on the surface of an S9H thallus, and an S9H-peg-LH10-antibody direct mediated agglutination test established based on the display expression on the surface of the S9H thallus can specifically recognize an anti-LH10 mAb in a hybridoma cell supernatant, so that the monoclonal antibody aiming at the B cell epitope peptide LH10 on the membrane protein LmPio can be quickly screened out.

The invention discloses a multiple qPCR (quantitative polymerase chain reaction) detection kit for simultaneously detecting four fimbriae genes of swine pathogenic escherichia coli and application of the multiple qPCR detection kit. The kit comprises primers and a TaqMan probe, wherein the primers and the TaqMan probe are respectively used for detecting F4, F17, F18 and F41 fimbriae genes of swine pathogenic escherichia coli. Experiments prove that the kit has the advantages of low cost, high specificity, high sensitivity, rapidness and reliability in detection, simplicity in operation and the like when being used for detection. According to recent epidemiological investigation results, 951 pig anus swab samples are detected by using the method, 662 positive samples are detected, the positive rate is 69.61%, the sensitivity of the method is higher than that of conventional PCR, and the total coincidence rate of the two results is greater than 90%. The method is suitable for rapid molecular diagnosis of swine pathogenic Escherichia coli, is an effective technical means for screening the virulence gene of the swine pathogenic Escherichia coli epidemic strain, and fills the blank of multiple fluorescent PCR detection technology in the field.

The invention discloses a bacterial surface modification method based on a programmable hairy DNA nanowire rod and application of the bacterial surface modification method. The method comprises the following steps: firstly, constructing a DNA nanowire rod structure with a three-dimensional structure by utilizing a DNA origami technology; respectively modifying the head end and the main body of the DNA nanowire rod structure with functional molecules; incubating the bacteria modified with the coupling group and the DNA nanowire rod structure modified with the functional molecule to obtain the DNA nanowire rod structure modified with the coupling group. The DNA nanowire rod structure constructed by the invention can be used for regulating and controlling the movement of bacteria, and the behaviors of the bacteria can be regularly adjusted by adjusting the geometrical shape and density of the DNA-based pilus analogues without gene manipulation. The DNA nanowire rod has modifiability, low toxicity and low immunogenicity, can be used for analyzing how the nanoscale appendage form controls movement, and lays a foundation for application in interface adaptability, colonization or engineering probiotic systems in the future.

The invention provides a method for detecting five virulence factors of enterotoxigenic escherichia coli in a pig farm based on 5-plex mPCR, and belongs to the technical field of biological detection. The multiplex PCR primer group comprises a primer pair used for detecting escherichia coli STa fimbriae genes, a primer pair used for detecting escherichia coli STb fimbriae genes, a primer pair used for detecting escherichia coli LTb fimbriae genes, a primer pair used for detecting escherichia coli STX2e fimbriae genes and a primer pair used for detecting escherichia coli EAST1 fimbriae genes. The invention provides a method for detecting five virulence factors of enterotoxigenic escherichia coli in a pig farm based on 5-plex mPCR. The aim of simultaneously, accurately and efficiently detecting the five most critical virulence factors (STa, STb, LTb subunit, STX2e and EAST1) of swine ETEC is achieved.

The present invention provides a conductive biofilm comprising a microorganism having cilia or pili and a conductive polymer bound to the cilia or pili. The present invention also provides a composite comprising a photocatalyst layer and a biofilm comprising a microorganism having cilia or pili. The invention also provides an artificial Z-some system. The artificial Z-some system comprises a photocatalyst layer and the conductive biofilm provided by the invention.

The invention provides a method for detecting five pilus adhesion subtypes of enterotoxigenic escherichia coli in a pig farm based on 5-plex mPCR, and belongs to the technical field of biological detection. The multiplex PCR primer group comprises a primer pair for detecting a fimbriae gene of escherichia coli F5, a primer pair for detecting a fimbriae gene of escherichia coli F18, a primer pair for detecting a fimbriae gene of escherichia coli F6, a primer pair for detecting a fimbriae gene of escherichia coli F4 and a primer pair for detecting a fimbriae gene of escherichia coli F41. The invention provides a method for detecting five fimbristin subtypes of enterotoxigenic escherichia coli in a pig farm based on 5-plex mPCR, which constructs a stable mPCR system capable of completing synchronous detection of five serum subtypes (F4, F18, F6, F41 and K99) at one time, and realizes synchronous detection of fimbristin genotypes.