29 results about "Hemolysin" patented technology

The invention belongs to the technical field of nano biological materials, and particularly relates to a preparation method of cell membrane coated nanoparticles based on solvent equilibrium and sulfydryl anchoring. According to the method, sulfydryl-containing lipid is doped into a membrane system, so that the sulfydryl-containing lipid and the surface of a substrate form a covalent anchor bond to enhance the membrane-substrate binding force, and a small amount of organic solvent is added to improve the fluidity of the lipid and promote spontaneous fusion and uniform spreading of a membrane layer on the surfaces of particles. And centrifuging and washing to obtain the cell membrane nanoparticles with completely coated surfaces. According to the method, high-energy ultrasonic or extrusion treatment is not needed, stable coating can be realized on the premise of maintaining complete composition of membrane protein and lipid, and the adhesion stability of a membrane layer in a high-salt and shearing environment is remarkably improved. The method is suitable for various nano substrates and different morphological structures, and the obtained particles show higher antibody titer and excellent safety in an anti-alpha-hemolysin vaccine model. The invention provides a mild and efficient bionic nano material construction strategy with wide applicability.

The application discloses active aggregation peptides and application thereof, and belongs to the technical field of bioengineering. The active aggregation peptides are derived from alpha-hemolysin HlyA of Escherichia coli CFT073, and comprise five sequences, namely HlyA218, HlyA60, H12, H1 and H2. The active aggregation peptides can mediate the active inclusion body formation of a target protein in a host cell by being fused with the target protein for expression, and the short peptides have high protein activity aggregation rate and the potential of stimulating the rapid growth of a recombinant bacterium. The active aggregation peptides can be applied to column-free purification and in-situ immobilization of a recombinant protein, and have low production cost and simple steps.

Provided herein, inter alia, are compositions and methods relating to α-Hemolysin polypeptide variants for translocation across phospholipid membranes.

The invention discloses a hemolysin-like protease inhibition composition for regulating vaginal micro-ecological balance as well as a preparation method and application of the hemolysin-like protease inhibition composition. The hemolysin-like protease inhibition composition disclosed by the invention is prepared from 10 to 20 percent of lactobacillus fermentation liquor, 10 to 30 percent of phloretin, 10 to 30 percent of naringenin, 30 to 40 percent of quercetin and 5 to 10 percent of sodium hyaluronate. The preparation method comprises the following steps: dissolving phloretin, naringenin, quercetin and sodium hyaluronate in 50% butanediol in proportion, and ultrasonically mixing uniformly to obtain a mixed solution; and slowly adding the mixed solution into the lactic acid bacteria fermentation solution, and uniformly stirring to obtain the hemolysin-like protease inhibition composition. According to the invention, natural active components with a hemolysin-like protease inhibition effect are screened to construct a synergistic system with three mechanisms of acidification environment regulation, enzyme activity inhibition and barrier repair, so that hemolysin-like protease can be directly inhibited, and the effect of inhibiting the hemolysin-like protease can be achieved by adjusting the local pH value and the micro-ecological environment of the vagina. Propagation of pathogenic bacteria is inhibited, and growth of dominant flora such as lactobacillus is promoted.

The present invention is in the fields of antibody technology, medicine, pharmacology, infection biology, and medical diagnostics. More specifically, the present disclosure provides VHH antibodies that prevent membrane binding and / or oligomerization of Staphylococcus aureus (HLA) alpha-hemolysin and HLA-mediated hemolysis.

Provided herein are compositions and methods for treating Staphylococcus aureus.

The present invention relates to a recombinant endolysin for controlling Clostridioides difficile infectious disease, and a use thereof, and, more specifically, to endolysin PHICD111_20024_EAD having excellent salt stability, and a use thereof. The endolysin PHICD111_20024_EAD, newly isolated in the present invention, exhibits specific activity against Clostridioides difficile, which is one of the causative bacteria of intestinal inflammation, and strains belonging to the genus Bacillus and Listeria monocytogenes, which are known as causative bacteria of food poisoning. The endolysin PHICD111_20024_EAD of the present invention does not affect humans and animals, and thus is safe and applicable to the pharmaceutical industry, food industry, biotechnology and the like, and also can effectively kill bacteria at a target site or target substance without problems related to antibacterial resistance.

This invention belongs to the field of lymphoma screening technology, specifically relating to a flow cytometry screening method for lymphoma. The method consists of the following steps: (1) taking an animal bone marrow or peripheral blood sample and placing it in a blood collection tube containing an anticoagulant, mixing until no clots remain, to obtain the sample to be tested; (2) adding 380 μL of white blood cells to the sample to be tested, stirring for 2-5 seconds, letting it stand for 5-10 minutes until the cell suspension completely turns brownish-red, then diluting it to obtain a sample containing 1×10⁻⁶ cells per 20 μL of the sample to be tested. 6 ~2×10 6 (3) Take NHL-1 and NHL-2 test tubes, add the test sample from step (1), add 2 mL of ammonium chloride hemolysin, shake to mix, incubate in the dark for 15-20 min, add the first physiological saline, centrifuge at 1500-2000 rpm for 3-5 min, discard the supernatant, shake to mix, add the first physiological saline again for washing, centrifuge at 1500-2000 rpm for 5-8 min, discard the supernatant, and retain about 100 μL of cell suspension; This invention can quickly screen for lymphoma.

This invention provides a recombinant Staphylococcus aureus nanoparticle protein HI-mi3, its preparation method, and its applications. This protein is composed of HI (containing the key SA virulence factor α-hemolysin Hla). H35L The fusion protein HI and mi3 are composed of the N2 functional domain of the iron ion surface determinant B and self-assembled nanoparticle protein mi3. This invention uses the SpyTag / SpyCatCher protein coupling system to link the fusion protein antigen HI and mi3, obtaining the Staphylococcus aureus self-assembled nanoparticle protein HI-mi3. Both the recombinant protein SpyCatcher-mi3 and the recombinant protein SpyTag-HI of this invention are induced to be expressed in soluble form in Escherichia coli. The recombinant protein SpyCatcher-mi3 of this invention can covalently bind to the recombinant protein SpyTag-HI via isopeptide bonds to form the HI-mi3 nanoparticle vaccine molecule, with simple binding conditions. The HI-mi3 nanoparticle vaccine of this invention can induce a high level of immune response in animals and exert an immunoprotective effect.

The invention discloses an application of Tirucalol in preparation of a medicine for treating and / or preventing bacterial infection. The Tirucalol has the capability of inhibiting expression of alpha-hemolysin to reduce the pathogenicity of staphylococcus aureus, and obviously prolongs the survival time of greater wax moth larvae on an animal infection model. The protection effect of Tirucalol on infection caused by staphylococcus aureus is not realized by directly inhibiting the growth of bacteria, so that the selective pressure on the bacteria is relatively small. The treatment window of Tirucalol is relatively high, the median inhibitory concentration of the Tirucalol for inhibiting the expression of alpha-hemolysin of the staphylococcus aureus JE2 strain is as low as 1.2 mu M, the median toxicity concentration (CC50) of the Tirucalol to human cells is greater than 100 mu M, and the Tirucalol has medical values of research, development and transformation. In addition, Tirucalol has an inhibiting effect on expression of alpha-hemolysin in different staphylococcus aureus strains, and can be widely applied to treatment of infection caused by the staphylococcus aureus strains.

The invention provides a recombinant streptococcus hemolysin O protein and a preparation method and application thereof, the recombinant streptococcus hemolysin O protein is obtained by mutating a protein with an amino acid sequence as shown in SEQ ID NO: 1, the mutations comprise fixed mutations or the mutations comprise fixed mutations and optional mutations, the fixed mutations comprise three point mutations, and the optional mutations comprise one or more optional point mutations. The two groups are respectively K301F, S438F and E462V; the optional mutation is any one or any combination of more than two of the following four point mutations: Q182I, D194V, Q302F and K406F. Compared with a natural recombinant streptolysin O protein, the recombinant streptolysin O protein disclosed by the invention has better antigen activity and higher thermal stability, and can be applied to an anti-streptolysin O antibody.

Provided are systems and methods that may be employed to detect the presence or absence of paroxysmal nocturnal hemoglobinuria (PNH) in a subject that includes a leukocyte including GPI-anchors the leukocyte incubated with one or more blocking agents each independently specific to one or more GPI-anchored proteins, the leukocyte further incubated with a pro-aerolysin or derivative thereof, and optionally a second leukocyte including GPI-anchors not incubated with one or more of the blocking agents. The systems may be used as a positive control in assays detecting the presence or absence of PNH.

Provided are systems and methods that may be employed to detect the presence or absence of paroxysmal nocturnal hemoglobinuria (PNH) in a subject that includes a leukocyte including GPI-anchors the leukocyte incubated with one or more blocking agents each independently specific to one or more GPI-anchored proteins, the leukocyte further incubated with a pro-aerolysin or derivative thereof, and optionally a second leukocyte including GPI-anchors not incubated with one or more of the blocking agents. The systems may be used as a positive control in assays detecting the presence or absence of PNH.

The invention establishes a method for simultaneously detecting vibrio parahaemolyticus, staphylococcus aureus, listeria monocytogenes, salmonella, shigella, bacillus cereus and vibrio alginolyticus on the basis of multiple PCR (Polymerase Chain Reaction) combined with a gene chip technology. The method comprises the following steps: selecting a heat-labile hemolysin gene of vibrio parahaemolyticus, a heat-resistant nuclease gene of staphylococcus aureus, a coded hemolysin O gene hlyA of listeria monocytogenes, an invasive protein A gene of salmonella enteritidis and an invasive plasmid antigen H gene of Shigella to carry out quintuple PCR (Polymerase Chain Reaction) amplification; bacillus cereus non-hemolytic toxin genes and vibrio alginolyticus similar Rpos sigma factor genes are selected for double PCR, two groups of multiplex PCR amplification products are hybridized with specific probes on the chip at the same time, and seven food-borne pathogenic bacteria can be detected at the same time. The method for detecting pathogenic bacteria by using the gene chip is high in specificity, high in sensitivity and strong in reliability.

Compositions and methods for treating urinary tract infection (UTI) and / or sepsis in a subject in need thereof are provided. Methods include administering to the subject a composition comprising an alpha-hemolysin (HlyA) inhibiting agent. In some embodiments, the HlyA inhibiting agent includes a soluble low-density lipoprotein receptor (LDLR)-Fc fusion protein as described herein, a clathrin-mediated endocytosis (CME) inhibitor, and / or an anti-LDLR antibody. In some embodiments, the soluble LDLR-Fc fusion protein includes an Fc domain and at least one LDLR type A domain. In some embodiments, the UTI and / or sepsis is caused by E. coli.

This invention relates to a sample processing reagent and its application in flow cytometry analysis, belonging to the field of flow cytometry analysis technology. The invention provides a sample processing reagent comprising a hemolysin and a cell-permeable agent. The hemolysin comprises tris(hydroxymethyl)aminomethane (Tris), sodium chloride, calcium chloride, disodium ethylenediaminetetraacetate, paraformaldehyde, and a solvent. The cell-permeable agent comprises sodium chloride, disodium hydrogen phosphate, sodium dihydrogen phosphate, nonylphenol polyoxyethylene ether, Triton X-100, paraformaldehyde, and a solvent. The hemolysin is mild and highly effective, providing complete hemolysis and clear cell clustering. The cell-permeable agent permeates the cell membrane under isotonic and neutral conditions, minimizing damage to cell surface antigens and effectively detecting both cytoplasmic and nuclear antigens.

This invention belongs to the field of biomedical technology and discloses an antitumor composition and its application of an engineered bacterium expressing hemolysin and a bisphosphonate compound. The composition comprises an engineered bacterium that targets and colonizes tumors and secretes hemolysin, and a bisphosphonate compound. The engineered bacterium specifically induces tumor hemorrhage; the secreted hemolysin lyses red blood cells, which are then phagocytosed by macrophages. The hemolysin then self-assembles with the bisphosphonate compound intracellularly, generating a large amount of reactive oxygen species, thereby remodeling the antitumor phenotype of tumor-associated macrophages and achieving an antitumor effect. Furthermore, the engineered bacterium does not induce bleeding in normal blood vessels and therefore has no effect on normal cells.

This invention belongs to the field of biomedical technology and discloses an α-hemolysin inhibitor and its application in the preparation of anti-infective drugs for Staphylococcus aureus. The inhibitor is mangiferin, and its novel use as a small molecule inhibitor of Staphylococcus aureus α-hemolysin (Hla) and related drug preparation methods are described. This invention, through in vitro hemolysis experiments, Hla protein purification and inhibitory activity verification, binding stability experiments, molecular docking studies, and in vivo animal experiments, confirms that mangiferin can efficiently and directly inhibit the hemolytic activity of Staphylococcus aureus supernatant and purified Hla protein in a dose-dependent manner; it can form a stable complex with Hla protein through hydrogen bonds and other interactions, blocking the pore-breaking activity of Hla in an irreversible or high-affinity binding manner, with a long-lasting inhibitory effect. This invention provides a novel candidate drug and technical solution for solving the problems of Staphylococcus aureus (including drug-resistant strains) infection and antibiotic resistance, with broad application prospects.

The application provides a probiotic crystal ball preparation containing lactobacillus jensenii and bifidobacterium longum, which comprises a shell structure and a core structure, wherein the shell structure comprises gelatin, glycerol and water; and the core structure comprises lactobacillus jensenii, bifidobacterium longum and hydrogenated oil. The lactobacillus jensenii has a preservation number of CCTCC NO: M2022172; and the bifidobacterium longum has a preservation number of CCTCC NO: M2019780. The application adopts a double-layer seamless capsule technology with gelatin as the shell material, hydrogenated oil and bacterial powder as the core, so that the probiotics can not be digested by gastric juice and have a high survival rate in the intestinal tract. Moreover, the core of the application uses the screened lactobacillus jensenii VHProbi A17 strain which does not produce hemolysin and cannot dissolve blood cells, and has safety. The lactobacillus jensenii has scavenging effects on DPPH free radicals and hydroxyl radicals, and has a wide antibacterial spectrum.

The invention relates to the technical field of medical detection, in particular to an antibody composition and application. The antibody composition is composed of a CD33 antibody, an HLA-DR antibody, a CD14 antibody, a CD16 antibody and a CD45 antibody. The invention also provides an application of the antibody composition in detection of a peripheral blood mononuclear cell subset. The invention also provides a peripheral blood mononuclear cell subset determination method, which comprises: adding the fluorescein-labeled antibody composition and PBS to a blood sample to be detected, incubating in a dark place, adding the PBS, washing, centrifuging, discarding the supernatant, adding hemolysin, standing in a dark place, adding the PBS, washing, centrifuging, discarding the supernatant, adding the PBS, and detecting the peripheral blood mononuclear cell subset. And performing flow cytometry on a machine for detection. The invention solves the problem that the false positive result is easily caused when the existing antibody combination is used for detecting the mononuclear cell subpopulation.

The invention discloses an application of a compound 3546847 in preparation of anti-staphylococcus aureus hemolysin medicines, and belongs to the field of microbial infectious diseases and medicines. The invention finds that the compound 3546847 can neutralize the toxicity of staphylococcus aureus hemolysin, and has a protective effect on MRSA staphylococcus aureus USA300 infected mice. The compound 3546847 can be applied to preparation of anti-staphylococcus aureus hemolysin medicines and medicines for preventing or treating staphylococcus aureus infection. The new medicinal value of the compound 3546847 is found, and a new medicine for preventing and treating staphylococcus aureus infection is provided; the compound 3546847 can neutralize the main virulence factor of staphylococcus aureus, namely hemolysin, so as to relieve inflammatory injury.

We have shown that cprA expression leads to the production of outer membrane vesicles (OMVs) that block autophagic flux and have a greater capacity to activate the non-canonical inflammasome pathway. In a murine model of sepsis, a P. aeruginosa strain deleted for cprA was less virulent than the wild-type strain. These results demonstrate the important role of CprA in the pathogenicity of P. aeruginosa. It is worth noting that CprA is also a functional ortholog of HlyF, which is encoded by virulence plasmids of Escherichia coli. We have shown that other cryptic SDRs encoded by mammalian and plant pathogens, such as Yersinia pestis and Ralstonia solanacearum are functional orthologs of CprA and HlyF. These SDRs also induce the production of OMVs which block autophagic flux. This study uncovers a new family of virulence determinants in Gram-negative bacteria, offering potential for innovative therapeutic interventions and deeper insights into bacterial pathogenesis. The present invention relates to a method for producing vesicles, the method comprising a step of expressing or overexpressing hemolysin F (hlyF) gene or an ortholog of hemolysin F gene in Gram-negative bacteria, said hlyF gene or ortholog of hlyF gene encoding respectively a HlyF protein or an ortholog of HlyF protein.

Polypeptides comprising hemolysin A (Hly A) fragments and / or variants and a peptide or polypeptide of interest in form of a fusion protein that exhibits improved expression and secretion as well as increased solubility and stability and improved renaturation efficiency. Also encompassed are nucleic acids encoding these polypeptides. host cells that comprise said nucleic acids, and methods and uses for protein expression using said nucleic acids, host cells and polypeptides.

summary This specification provides compositions and methods for the treatment of Staphylococcus aureus.

This invention discloses a detection kit and method for abnormal lymphocytes, myeloid blast cells, and acute promyelocytic leukemia. The detection kit includes a first reagent and a second reagent. The first reagent includes a hemolysin and a staining agent. The second reagent includes a hemolysin, a staining agent, and an antibody treatment agent, including CD13 and CD34 antibody treatment agents. The hemolysin, based on a total volume of 1L, includes the following components: 0.1-10g castor oil polyoxyethylene ether nonionic surfactant, 0.01-10g cationic surfactant, 0.5-15g buffer, 0.01-8g preservative, with the remainder being water. The pH value of the hemolysin is 5-9. The staining agent, based on a total volume of 1L, includes the following components: 0.001-0.2g nucleic acid dye, with the remainder being a solvent. The detection method includes: obtaining a blood sample to be tested, preparing a first sample, testing the first sample, preparing a second sample, and testing the second sample. This invention can accurately detect abnormal lymphocytes, myeloid blast cells, and diagnose acute promyelocytic leukemia.

Provided herein are compositions and methods for the treatment of Staphylococcus aureus.

The invention discloses an application of a compound L604-0819 in preparation of anti-staphylococcus aureus hemolysin medicines, and belongs to the field of microbial infectious diseases and medicines. The invention finds that the compound L604-0819 can neutralize the toxicity of staphylococcus aureus hemolysin, has a protective effect on MRSA staphylococcus aureus USA300 infected mice, and has the application of preparing a staphylococcus aureus hemolysin resisting medicine and a staphylococcus aureus infection preventing or treating medicine. According to the invention, the new medicinal value of the compound L604-0819 is found, and a new medicine for preventing and treating staphylococcus aureus infection is provided; the compound L604-0819 can neutralize the main virulence factor of staphylococcus aureus, namely hemolysin, so that inflammatory injury is relieved.

The present invention belongs to the fields of infectious microbial diseases and medicines. Provided is the use of compound 5928-0054 in the preparation of a drug against Staphylococcus aureus hemolysin. It is found that compound 5928-0054 can neutralize the toxicity of Staphylococcus aureus hemolysin, exhibits a protective effect on mice infected with MRSA Staphylococcus aureus USA300, and can be used in the preparation of a drug against Staphylococcus aureus hemolysin and a drug for preventing or treating Staphylococcus aureus infections. Compound 5928-0054 is found to have a new pharmaceutical value, i.e. providing a new drug for the prevention and treatment of Staphylococcus aureus infections. Compound 5928-0054 can neutralize hemolysin, the major virulence factor of Staphylococcus aureus, thereby alleviating inflammatory injuries.

This application discloses a method for preparing spirulina bioactive peptides based on yeast co-fermentation. It belongs to the field of biotechnology. This invention is the first to disclose the use of *Pichia pastoris* to co-ferment spirulina powder with glucose, successfully preparing spirulina bioactive peptides. Compared with traditional enzymatic hydrolysis, this co-fermentation method significantly increases the yield of bioactive peptides to 5.048% under mild conditions (28℃, 24h), representing a maximum increase of 131.4% compared to traditional enzymatic hydrolysis. The obtained bioactive peptides exhibit excellent efficacy in immunological experiments, significantly reversing immunosuppression-induced inhibition of mouse weight gain, increasing spleen index, and completely restoring serum hemolysin levels, with a dose-dependent effect. This method effectively solves the problems of low yield, demanding conditions, high cost, and easily compromised product activity associated with traditional enzymatic hydrolysis, providing an innovative, economical, and green technical solution for the efficient preparation of highly active spirulina peptides.