72 results about "Hemolysin" patented technology

The invention provides a sample pretreatment automation method for flow cytometry, and belongs to the technical field of sample pretreatment for flow cytometry. A biological sample to be detected is collected and placed in a collection tube containing an EDTA-K2 anticoagulant for pretreatment; an automatic pipetting system is used for carrying out incubation reaction on an anticoagulant whole blood sample and an intelligent matching fluorescence labeling antibody mixed solution, and a double-layer game optimization verification system is used for verifying the rationality of an antibody adding proportion and reaction condition parameters; carrying out fluorescence characteristic readability index prediction on the incubated cell suspension by adopting an intelligent dilution parameter regulator model, dynamically adjusting hemolysis parameters and suspension conditions, and adding 1 * hemolysin working solution by using an automatic liquid adding device to carry out hemolysis treatment so as to finish pretreatment; the technical problems that in the pretreatment process of flow cytometry detection samples, parameters are often based on artificial experience, and the reproducibility and standardization degree of detection results are insufficient are solved.

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.

Described herein are variants of alpha-hemolysin having at least one mutation, such as a mutation to a positive charge. In certain examples, the mutation is selected from V149K, E287R, H35G, T109K, P151K, K147N, E111N, M113A, or combinations thereof in the mature, wild-type alpha-hemolysin amino acid sequence. The α-hemolysin variants may also include a substitution at H144A and / or a series of glycine residues spanning residues 127 to 131 of the mature, wild-type alpha hemolysin. Also provided are nanopore assemblies including the alpha-hemolysin variants, the assembly having a decreased time-to-thread. The decreased time-to-thread, for example, increases DNA sequencing efficiency and accuracy.

A therapeutic agent comprising Lon protease, or a variant or active fragment thereof, alpha-hemolysin, or a variant or active fragment thereof, CK1α1, or a variant or active fragment thereof, a c-MYB inhibitor and / or a CEBP-δ inhibitor, for use in therapy, with the proviso that the therapeutic agent does not comprise a bacteria or bacterial supernatant. Methods of production and use thereof.

The invention discloses a method for detecting polypeptide sequence difference and post-translational modification thereof based on a nanopore system, the nanopore system is constructed in the method, and the nanopore system comprises an alpha-hemolysin nanopore and octa-amino modified gamma-cyclodextrin embedded in the nanopore; the amino acid sequence of the alpha-hemolysin nanopore comprises mutation sites M113R and T145R, and the alpha-hemolysin nanopore is characterized in that the alpha-hemolysin nanopore According to the detection method, polypeptide with negative charges enters a nanopore under the driving of external voltage, an ion current blocking signal is recorded, and the polypeptide sequence difference and post-translational modification are analyzed according to blocking amplitude, duration, noise characteristics and event frequency. The method can detect a peptide chain with the length of 2-10 amino acid residues, can distinguish the post-translational modification state in homopolypeptide composed of 4-10 amino acids and polypeptide by single amino acid resolution, and can be used for protein enzyme digestion product analysis, oligopeptide drug detection and rapid polypeptide identification under the condition of no mass spectrum.

The embodiment of the invention relates to a sample analyzer and a sample analysis method. The sample analysis method comprises the following steps: sucking a to-be-detected blood sample; mixing at least one part of the blood sample to be tested, the hemolytic agent, the first dye and the second dye to prepare a test sample; in a single test, each particle in a measurement sample passes through an optical detection zone irradiated by excitation light one by one to acquire optical information including scattered light information, first fluorescence information, and second fluorescence information, the exciting light comprises light of a first wavelength capable of exciting the first dye and light of a second wavelength capable of exciting the second dye, and the second wavelength is larger than the first wavelength; and obtaining a white blood cell four-classification result and a counting result of a nucleated red blood cell group of the test sample based on the at least one kind of scattered light information, the first fluorescence information and the second fluorescence information. Therefore, the leukocyte classification result and the nucleated red blood cell counting result can be obtained at the same time in one test.

The invention discloses a multivalent expression sheep listeria vaccine for cervical cancer and a preparation method thereof, and the method comprises the following steps: on the basis of replacing sheep listeria LI [delta] ilo:: hly with hemolysin, constructing to obtain auxotrophic sheep listeria LI [delta] ilo:: hly [delta] dal [delta] dat; the fusion antigen is constructed by alternately arranging amino terminal and carboxyl terminal structural domains of four types of HPV6 / 11 / 16 / 18 E6 and E7 proteins and retaining an overlapping region of 16 amino acids at a connecting site; inserting the fusion antigen into a non-resistance plasmid pCW631 which carries a dal gene and replaces an Amp gene with an asd gene, so as to obtain a non-resistance plasmid pCW636; the resistance-free plasmid pCW636 is electrically transferred into the auxotroph sheep listeria monocytogenes LIdeltailo:: hly deltadal deltadat, and the sheep listeria monocytogenes cervical cancer vaccine is obtained. The cervical cancer vaccine provided by the invention can express the E6E7 protein in a multivalent manner, so that multiple protection on cervical cancer is realized.

The invention provides a blood culture bottle capable of rapidly and accurately detecting, and belongs to the technical field of blood culture bottle preparation. A culture solution in the blood culture bottle comprises brain heart immersion liquid, SPS, activated carbon and hemolysin. The hemolysin is added into the blood culture bottle, so that the bacteria and the blood cells are conveniently distinguished, the blood cells are prevented from interfering bacteria counting to influence a detection result, and finally, the negative and positive properties are determined through Coulter counting. Therefore, the problems that a traditional blood culture bottle needs long-time culture and blood cells are not completely adsorbed by resin, so that a detection result is possibly influenced can be avoided, and the culture time can be compressed to 2 hours by determining the positive and negative properties through Coulter counting without a traditional positive reporting mode.

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.

The present invention pertains to the fields of antibody technology, medicine, pharmacology, infection biology, and medical diagnostics. More specifically, the present disclosure provides VHH antibodies that neutralize cytotoxic gamma-hemolysins and optionally the leukocidin LukF of S. aureus. These VHH antibodies are useful in an approach for co-neutralizing alpha- and gamma-hemolysins and the LukSF toxin pair by multimeric VHH-fusions. The invention provides an implementation of this approach.

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.

The invention discloses a streptolysin 'O' polymer as well as a preparation method and application thereof. The streptolysin 'O' polymer is formed by cross-linking 2-8 streptolysin 'O' protein monomers through a cross-linking agent, and the polymer can be coupled with a marker or a solid-phase carrier to form a polymer conjugate. The polymer and the polymer conjugate can be used for preparing a detection reagent for detecting antistreptolysin O, the reactivity of the polymer and the polymer conjugate with the antistreptolysin O is remarkably higher than that of a detection reagent prepared from corresponding protein monomers, and the polymer and the polymer conjugate have the advantages of high detection sensitivity and good accuracy.

The invention belongs to the technical field of microorganisms, and particularly relates to bifidobacterium longum subsp. Infantis, a probiotic preparation and application of the probiotic preparation in products for reducing blood sugar and blood lipid. The bifidobacterium longum subsp. Infantis provided by the invention is bifidobacterium longum subsp. Infantis A32-03, and the preservation number is CGMCC (China General Microbiological Culture Collection Center) No.32811. The strain does not generate hemolysin, does not have nitrate reductase activity, does not generate any harmful metabolites such as biogenic amines and indoles, is sensitive to various antibiotics, and is good in biological safety. Particularly, the probiotic preparation obtained by fermenting the bifidobacterium longum subsp. Infantis A32-03 in a culture medium containing the auricularia auricula polysaccharide has a prominent inhibition effect on alpha-amylase, alpha-glucosidase and lipase, has an excellent degradation capability on cholesterol, has a good blood sugar and blood fat regulation effect, and can be used for preparing the probiotic preparation. The method has good popularization value in oral administration of medicines for reducing blood sugar and blood fat or health-care food for regulating blood sugar and blood fat.

Provided herein are compositions and methods for treating Staphylococcus aureus.

The invention discloses a flavonoid compound with an effect of reducing MRSA toxicity and application of the flavonoid compound in neutralizing alpha-hemolysin, and belongs to the technical field of medicinal chemistry. The flavonoid compounds can inhibit secretion of MRSA to alpha-hemolysin (Hla), so that the infection toxicity of MRSA to a host is reduced, and meanwhile, the compounds do not inhibit growth of MRSA, so that generation of drug resistance of MRSA can be greatly reduced. Besides, the compounds can also neutralize alpha-hemolysin (Hla) and have important medical value in clinical diagnosis and treatment, on one hand, damage of MRSA to a host immune system can be reduced, and on the other hand, the compounds are used for treating diseases caused by MRSA and reducing generation of MRSA drug resistance, so that the compounds have important significance in prevention and treatment of MRSA.

The invention discloses bifidobacterium breve HX-5M3 and application thereof, and belongs to the technical field of biomedicine. The bifidobacterium breve HX-5M3 disclosed by the invention is preserved in the China Center for Type Culture Collection, and the preservation number of the bifidobacterium breve HX-5M3 is CCTCC (China Center for Type Culture Collection), and the preservation number of the bifidobacterium breve HX-5M3 is CCTCC NO: M 20242244. The invention also discloses an application of the bifidobacterium breve HX-5M3 in preparation of a product for metabolizing oligosaccharide in breast milk. The strain HX-5M3 disclosed by the invention not only can efficiently utilize LNT and LNnT, but also shows good metabolic capability on 2 '-FL and 3-FL; the strain can tolerate cholate, has good intestinal colonization potential, is sensitive to various antibiotics, and does not produce hemolysin. The strain HX-5M3 disclosed by the invention has a large number of GHs genes related to HMOs metabolism, which indicates that the strain HX-5M3 has a relatively strong utilization capability on decomposing carbohydrates, especially on HMOs.

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.

The invention discloses bifidobacterium longum subsp. Infantis HX-4M1 and application thereof, and belongs to the technical field of biomedicine. The bifidobacterium longum subsp. Infantis HX-4M1 disclosed by the invention is preserved in the China Center for Type Culture Collection, and the preservation number of the bifidobacterium longum subsp. Infantis HX-4M1 is CCTCC (China Center for Type Culture Collection) NO: M 20242243. The invention also discloses an application of the bifidobacterium longum subsp. Infantis HX-4M1 in preparation of a product for metabolizing oligosaccharide in breast milk. The strain HX-4M1 not only can efficiently utilize LNT and LNnT, but also shows good metabolic capability to 2 '-FL and 3-FL, can tolerate cholate, has good intestinal colonization potential, is sensitive to various antibiotics and does not generate hemolysin, has a large number of GHs genes related to HMOs metabolism of the strain HX-4M1, and contains typical HMOs metabolism gene clusters of model strains.

The present invention is in the fields of antibody technology, medicine, pharmacology, infection biology and medical diagnosis. More particularly, the present disclosure provides VHH antibodies that prevent membrane binding and / or oligomerization of Staphylococcus aureus (S. aureus) alpha-hemolysin (HLA), as well as the hemolysis effects caused thereby.

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.

The invention discloses a gene editing system for developing a Staphylococcus aureus mastitis resistant Holstein cow aiming at an ADAM10 gene and application of the gene editing system. According to the invention, a novel single-base gene editing ABE technology is used to carry out gene editing on dairy cow fibroblasts, amino acids at main action sites of cell surface receptors ADAM10 of alpha-hemolysin are mutated, and the affinity activity between the two is reduced. Experiments prove that compared with a wild type, the inflammatory sensitivity of the mutated cow mammary epithelial cells to alpha-hemolysin is greatly reduced. Then, gene editing individuals are cultivated through cell nucleus transfer and embryo transfer technologies, and the mastitis resistance of the individuals is achieved.

The embodiment of the invention relates to a sample analyzer and a sample analysis method. The sample analysis method comprises the following steps: sucking a to-be-detected blood sample; mixing at least one part of the blood sample to be tested, the hemolytic agent, the first dye and the second dye to prepare a test sample; in a single test, the particles in the measurement sample pass through the optical detection area irradiated by the excitation light one by one to obtain optical information. The optical information includes scattered light information, first fluorescence information, and second fluorescence information. The result of counting a neutrophil population, the result of counting a lymphocyte population, the result of counting a monocyte population, the result of counting an eosinophil population, and the result of counting a basophil population in the measurement sample are acquired on the basis of the at least one type of scattered light information and the first fluorescence information. And correcting the counting result of the basophilic granulocyte population based on at least the second fluorescence information, thereby obtaining an accurate counting result of the basophilic granulocyte population.

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 belongs to the technical field of microbial engineering, and particularly relates to leuconostoc mesenteroides subsp. Mesenteroides YWN-1 with the effects of benefiting qi, nourishing blood and enhancing immunity and application of the leuconostoc mesenteroides subsp. Mesenteroides YWN-1. The preservation number of the leuconostoc mesenteroides subsp. Mesenteroides YWN-1 is CGMCC No.34608. The leuconostoc mesenteroides subsp. Mesenteroides YWN-1 can significantly improve immune organ thymus and spleen injuries caused by deficiency of qi and blood, increase the number of red blood cells, hemoglobin and platelets of mice with deficiency of qi and blood, and have the efficacy of improving deficiency of both qi and blood. The phagocytic index, the serum hemolysin content, the half hemolysis value and the immune factor IgG and IgM content of mice with low immunity are improved, and the effects of improving immunity and resistance are achieved.

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.

The invention relates to a detection method of highly pathogenic photobacterium damsonii subspecies, and belongs to the technical field of detection. The Latin name of the high-pathogenicity photobacterium damsela subspecies is Photobacterium damsela subspecies, and the high-pathogenicity photobacterium damsela subspecies contains a characteristic virulence gene, namely, a hemolysin gene sequence; the method comprises the following steps: detecting a hemolysin gene sequence of the highly pathogenic photobacterium damselysin subspecies by using an enzymatic isothermal amplification (ERA) technology; the primer sequence of the ERA is Pdd-F1; r < d-R < 1 >; according to the direction from the 5'tail end to the 3 'tail end, the nucleotide sequence of the Pdd-F1 is a sequence number (ID): 1; the nucleotide sequence of the Pdd-R1 is shown as a sequence number (ID): 2. The detection method provided by the invention has the characteristics of high specificity, high sensitivity, rapidness and convenience.