69 results about "Enterobacter sp" patented technology

The invention discloses a method for improving the solubility and thermal stability of sweet protein, and belongs to the technical field of biosynthesis, the method comprises the following steps: constructing a gene tandem recombinant plasmid containing a monellin x-3C-sfGFP-3C-monellin y expression cassette, x is greater than or equal to 1, y is greater than or equal to 1, 5 is greater than or equal to x + y is greater than or equal to 3, a 3C protease recognition sequence is also inserted between adjacent copies of monellin, and each monellin is connected with a purification tag; the gene tandem recombinant plasmid is transformed into escherichia coli and inducible expression is carried out, thalli are split and purified to obtain fusion protein, 3C protease is used for enzyme digestion, and the target protein is obtained after re-purification. The total protein yield and the solubility proportion are remarkably improved by adopting a series construction mode of plasmids, meanwhile, the stability of monellin is effectively improved, the purification step is simpler and more convenient, and the method is suitable for industrial production.

The present disclosure provides a recombinant Escherichia coli strain modified by metabolic engineering means and a method for producing L-homoserine by using the same. The strain, designated as Escherichia coli having a strain number of 13-XA, is deposited in China General Microbiological Culture Collection Center (CGMCC) with an accession number of CGMCC No. 25099, dated Jun. 16, 2022. With respect to the chromosome DNA thereof, one or more genes associated with fatty acid metabolism are knocked out or attenuated, and / or a promoter is replaced for enhancement; one or more genes associated with the L-homoserine metabolic pathway are knocked out or attenuated, and / or one or more genes associated with the L-homoserine metabolic pathway are overexpressed or enhanced, and / or one or more genes associated with the L-homoserine metabolic pathway are mutated.

The invention discloses a conservative B cell epitope peptide of goose parvovirus VP3 protein, a nucleic acid molecule, a recombinant vector and application thereof. Conservative B cell epitope EW12 is inserted into F18 Escherichia coli Fod fimbriae, inert carrier bacteria S9H are introduced, recombinant bacteria capable of functionally exhibiting and expressing the EW12 conservative B cell epitope on the surface of the bacteria are obtained, the recombinant bacteria can specifically generate specific binding reaction with gosling plague egg yolk antibody and gosling plague vaccine immune serum, and the gosling plague egg yolk antibody and the gosling plague vaccine immune serum can be specifically combined with the gosling plague egg yolk antibody and the gosling plague vaccine immune serum. The method has the advantages that macroscopic agglutination particles are generated, cross agglutination reaction with other pathogen positive serum and healthy goose serum is avoided, the method is good in sensitivity, and the specific antibody can be detected in the 5th day after immunization at the earliest. A plate agglutination test directly mediated by the goose parvovirus VP3 protein conservative B cell epitope peptide EW12 has the advantages of specificity, sensitivity, convenience in operation and suitability for on-site large-scale rapid detection, and is expected to provide a new technical means for diagnosis, prevention and control and purification of GPV infection.

The invention relates to a microbial agent for degrading COD (Chemical Oxygen Demand) in DBP (Dibutyl Phthalate) wastewater as well as a preparation process and application of the microbial agent. The microbial agent is prepared from the following active components in parts by weight: 88 to 91 parts of pseudomonas, 5.2 to 5.6 parts of enterobacter and 0.05 to 0.11 part of alcaligenes. According to the application, a plurality of microbial strains are formed in the microbial liquid which is subjected to mixed domestication culture of the DBP wastewater, the anaerobic sludge, the hydrolytic acidification bacteria and the nutritive salt, and a plurality of microbial strains in the microbial agent which is obtained by mixing the microbial liquid after bacteria screening and expanding culture have a synergistic effect, so that the microbial agent has the performance of efficiently degrading COD in the DBP wastewater in an environment-friendly manner.

The invention discloses a multifunctional composite flora capable of degrading atrazine at low temperature and increasing phosphorus as well as a preparation method and application of the multifunctional composite flora, and relates to the technical field of farmland soil pollution microbial remediation. The invention aims to solve the problem of poor atrazine pollution remediation effect of a single strain in a low-temperature environment. The preparation method comprises the following steps: mixing a simple pure bacillus C1 bacterial solution, an enterobacter (Enterobacter sp.) P1 bacterial solution and an Acinetobacter lwoffii DNS32 bacterial solution, so as to obtain the multifunctional composite flora capable of degrading the atrazine at the low temperature and increasing the phosphorus, which is disclosed by the invention, and the preparation method comprises the following steps: mixing the bacterial solution of the simple pure bacillus, the bacterial solution of the enterobacter (Enterobacter sp.) P1 bacterial solution and the bacterial solution of the Acinetobacter lwoffii DNS32 bacterial solution, so as to obtain the multifunctional composite flora capable of degrading the atrazine at the low temperature and increasing the phosphorus. The invention can obtain the multifunctional composite flora capable of degrading atrazine at low temperature and increasing phosphorus as well as the preparation method and the application of the multifunctional composite flora.

Primers for of amplifying DNA from shiga toxin producing E. coli (STEC); methods of amplifying STEC DNA; and methods of detecting STEC.

Antimicrobial eyewear features frames infused with or coated with antimicrobial additives, thereby offering continuous protection by actively destroying and inhibiting the growth of bacteria, fungi, parasites, and some viruses. The lenses may also have an antibacterial coating that destroys and inhibits bacterial growth. In some examples, the lenses are treated with a specialized strengthening liquid, wherein the liquid contains nano components that release heavy metal ions capable of invading the cell walls of bacteria, leading to bacterial elimination, destroying DNA molecules and proteases within the bacterial cells, denature viral proteins, break DNA chains, and result in cell death. Additionally, the strengthening liquid reduces dehydrogenase activity and interacts with various protein groups within the cell, thereby reducing the activity of these groups and effectively inhibiting the growth of E. coli and other bacteria on the lens surface.

The application discloses a soil enterobacter capable of efficiently degrading polypropylene and application thereof. The strain is FJNUIM-S2, which is classified and named as soil enterobacter (Enterobacter agglomerans) Enterobacter soli ), is preserved in the China General Microbiological Culture Collection Center (CGMCC), and is preserved on October 17, 2024, with a preservation number of CGMCC No. 32241 and a preservation address of No. 3, Institute of Microbiology, Chinese Academy of Sciences, Xiliujiaobei, Chaoyang District, Beijing. The strain FJNUIM-S2 of the application can grow with polypropylene as the only carbon source, has good polypropylene degradation characteristics, provides a microbial resource for bioremediation of waste polypropylene in the environment, and has a wide application prospect.

The application belongs to the field of enzyme engineering and biotechnology, and discloses a 4-hydroxybenzoic acid hydroxylase mutant and application thereof in synthesis of gallic acid or a salt thereof. The 4-hydroxybenzoic acid hydroxylase mutant is obtained through directional evolution modification and high-throughput screening, and has an increased protocatechuate hydroxylase activity by more than 4 times. The 4-hydroxybenzoic acid hydroxylase mutant is expressed by using E. coli, and the obtained recombinant E. coli can efficiently catalyze the conversion of protocatechuate into gallic acid. The 4-hydroxybenzoic acid hydroxylase mutant is expressed in the recombinant E. coli for producing protocatechuate, and the obtained recombinant E. coli can de novo synthesize gallic acid from glucose as a substrate, and the yield reaches 58.65 g / L, and the residual amount of protocatechuate is only 0.33 g / L. The application solves the problem of a large amount of residual protocatechuate in the fermentation process of the existing strains, and can provide an efficient enzyme element for the creation of gallic acid industrial strains.

The invention provides an escherichia coli engineering bacterium for high yield of yellow cochineic acid and a construction method of the escherichia coli engineering bacterium, and a modified chassis cell escherichia coli BAP1-pflB is obtained by performing gene knockout on a pflB gene in an escherichia coli thallus BAP1. And the constructed recombinant plasmid pET30a-antDEFBG + zhuIJ is electrically transformed into escherichia coli BAP1-pflB, so that the engineering bacterium BAP1-pflB-PFK capable of producing the yellow cochineic acid is obtained. Through HPLC (High Performance Liquid Chromatography) detection, after the gene pflB is knocked out, the yield of the yellow cochineic acid is obviously increased. Yellow carmine acid synthesized by the escherichia coli engineering bacteria is a high-grade precursor of carmine acid with high commercial value, and plays an important role in the fields of textiles, skin care products and the like.

The application discloses a CMV virus-like particle for producing a VLP recombinant vaccine and a preparation method thereof, the CMV virus-like particle is obtained by cloning a C-terminal G4SLPETG modified plant virus cucumber mosaic virus CMV capsid gene into a prokaryotic expression vector to obtain a recombinant expression vector, the recombinant expression vector is transfected into E. coli BL21 (DE3), and expression is obtained through the recombinant E. coli BL21 (DE3); and the amino acid sequence of the C-terminal G4SLPETG modified CMV is SEQ ID NO. 1. Test proves that the recombinant strain constructed by the application is stable to expression of an exogenous protein. The recombinant protein expressed by the application is used for preparing a virus-like particle for antigen coupling, the coupling efficiency is high, the antigen purity is high, the safety is good, the virus-like particle is not pathogenic to mice and other animals, and the safety evaluation is easy.

The invention provides a bacterium with polyethylene plastic degradation activity and application thereof, and belongs to the technical field of polyethylene plastic degradation. The bacterium with the activity of degrading the polyethylene plastic, provided by the invention, comprises at least one of pseudomonas putida ZSA123 with the preservation number of CGMCC (China General Microbiological Culture Collection Center) No.34958 and enterobacter hormaechei LBA140 with the preservation number of CGMCC No.34957. The bacterium provided by the invention can obviously reduce the load, tensile stress and fracture displacement rate of a polyethylene plastic film, and when the bacterium is used for degrading polyethylene plastic, a relatively high weight loss rate can be achieved while the degradation time is shortened, and the degradation rate of the bacterium on the polyethylene plastic is far higher than that of an existing strain in the field.

According to the pogostemon cablin bacterial wilt original strain and the application thereof, enterobacter adami M42 is separated from the stem base part of a pogostemon cablin plant suffering from bacterial wilt, and the enterobacter adami M42 has pathogenicity to the plant after being inoculated with a pogostemon cablin seedling. Therefore, the enterobacter adamsii M42 can be used as a standard strain for pogostemon cablin variety disease resistance evaluation, chemical and biological agent indoor toxicity determination, field agent prevention and control research, pathogen specificity detection method development, plant-pathogen interaction mechanism research and the like. According to the application, a plurality of reagents with excellent inhibition effects are screened out through an inhibition test on enterobacter adamsii M42 and are used as the pogostemon cablin bacterial wilt prevention and treatment medicament.

The invention discloses a construction method of a crisprcas9 visual model based on fluorescent Escherichia coli, a red fluorescent protein gene is introduced into an Escherichia coli BL21 genome to construct a mcherry Escherichia coli model, and an easy-to-use biological model capable of verifying a Crisper / cas9 knockout effect and fluorescent Escherichia coli which can be quantified, is easy to observe, is high in sensitivity and is low in background are obtained.

The invention discloses a preparation method and application of a low-temperature-resistant growth-promoting complex microbial inoculant, and relates to the technical field of microorganisms. The method comprises the following steps: mixing a bacterial solution of Enterobacter sp. DNCS-S1 (P1), a bacterial solution of Enterobacter sp. DNCS-S2 (P2) and a bacterial solution of Pseudomonas sp. DNLK-S1 (K5), and inoculating the mixture into an LB liquid culture medium with the volume fraction of the inoculation amount being 1%; shaking and culturing at 4-6 DEG C for 3-4 days to obtain the low-temperature-resistant growth-promoting complex microbial inoculant. The low-temperature-resistant growth-promoting complex microbial inoculant is applied to plant growth promotion under low-temperature stress. The invention can obtain the preparation method and the application of the low-temperature-resistant growth-promoting complex microbial inoculant.

The application discloses a kind of plant salt stress tolerance improving rhizosphere growth promoting bacteria composition and application thereof, belong to microbial application technical field.The rhizosphere growth promoting bacteria composition of the application includes Bacillus subtilis BK73 with accession number CGMCC NO.32725 and Enterobacter ludwigii FZ20 with accession number CGMCC NO.32550.Bacillus subtilis BK73 has the activity of producing ACC deaminase, can synthesize gamma-polyglutamic acid, and Enterobacter ludwigii FZ20 has the ability of nitrogen fixation, phosphorus dissolution and IAA production.Plant experiments show that the rhizosphere growth promoting bacteria composition provided by the application exerts the synergistic effect between strains, and has obvious promoting effect on the germination of corn seeds under salt stress, the growth of corn plants and the salt stress tolerance of corn plants.The application provides a new growth promoting bacteria composition for improving plant salt tolerance, and has wide application prospect.

This invention relates to a quantitative method for ultrasonic disruption of *E. coli* cells, specifically a method based on firefly luciferase in *E. coli* cells. The method involves mixing *E. coli* expressing firefly luciferase as an internal standard with a suspension of target protein-expressing bacteria, followed by ultrasonic disruption of the cells. The degree of disruption of the target protein-expressing bacterial suspension is quantitatively calculated by measuring the activity of the firefly luciferase. The target protein-expressing bacterial suspension uses *E. coli* expressing the target protein. Compared with existing technologies, this invention overcomes the shortcomings of complex experiments, low efficiency, and unstable accuracy in existing technologies. It achieves efficient and highly accurate quantification of the degree of ultrasonic disruption of *E. coli* cells, reduces experimental complexity, and improves research and development efficiency and accuracy. This provides a scientific basis and new approach for the development of new feed protein resources and livestock breeding research, and has broad application potential.

The invention belongs to the technical field of microorganisms, and relates to a streptococcus salivarius subsp. Thermophilus Ss-PG-10 strain for relieving hyperuricemia and a preparation method of the streptococcus salivarius subsp. Thermophilus Ss-PG-10 strain. The strain provided by the invention is streptococcus salivarius subsp. Thermophilus Ss-PG-10, the classification name of the strain is Streptococcus salivarius subsp. Thermophilus, and the preservation number of the strain is CGMCC (China General Microbiological Culture Collection Center) No. 31867. The streptococcus salivarius subsp. Thermophilus Ss-PG-10 is separated from pickled Chinese cabbages, has a function of relieving hyperuricemia, has a certain antibacterial effect on pathogenic bacteria such as staphylococcus aureus, bacillus subtilis and escherichia coli, and has relatively strong acid resistance, cholate resistance and artificial simulated gastrointestinal fluid resistance.

This invention belongs to the field of biosensing and fiber optic detection technology, and discloses a photoelectric-coupled fiber optic real-time in-situ detection system for monitoring the adsorption process of *E. coli* (DH5α). Addressing the core pain points of existing *E. coli* detection technologies, such as reliance on complex sample pretreatment (taking over 24 hours) and the inadequacy of false positives and sensitivity with single-fiber SPR or electrochemical detection, which fail to capture the dynamic process of bacterial adsorption, this invention uses a fiber optic SPR probe with a dual recognition layer consisting of a surface-modified dopamine polymer membrane, an LPS-specific nucleic acid aptamer, and a *E. coli* shape-imprinted cavity as the working electrode. It simultaneously acquires SPR resonance wavelength shift and electrochemical current signals, achieving cross-validation of multi-dimensional detection results. The system can be in-situ implanted into complex detection systems such as water samples and food homogenates without labeling. It exhibits strong anti-interference capabilities and high detection specificity, and can track the entire dynamic process of *E. coli* adsorption-desorption in real time. It can be widely applied in scenarios such as rapid on-site screening of foodborne pathogens, research on bacterial interfacial adsorption mechanisms, and monitoring of microbial pollution in aquatic environments.

This invention relates to the field of genetic engineering technology, and particularly to TEV protease mutants, their preparation methods, and applications. This invention modifies the TEV enzyme molecule, with mutation points differing from those reported in previous studies. This enhances the activity of the TEV protease at the molecular level. Furthermore, this invention utilizes CRISPR / Cas9 gene editing techniques to modify the host bacterial chassis, obtaining engineered strains that express TEV at high yields. Further, the provided high-density fermentation control method can rapidly promote TEV enzyme expression, resulting in high E. coli cell yield, with an OD600 value reaching approximately 150, a cell wet weight of 80–130 g / L, and high expression levels of the target protein, accounting for 40%–64% of the total bacterial protein. Simultaneously, the method provided by this invention is simple and easy to implement, using readily available raw materials, achieving good application results while reducing production costs, resulting in significant economic benefits.

The invention discloses a construction method and application of an engineering bacterium for increasing the yield of alpha-ketoglutaric acid. Wild E.coli.W3110 serves as a chassis strain, lactic dehydrogenase ldhA, pyruvate dehydrogenase poxB and formic acid C-acetyltransferase pflB are knocked out firstly, and the flow direction of pyruvic acid to lactic acid, acetic acid and formic acid is blocked; meanwhile, the promoter PBBaJ23109 is used for replacing a natural promoter of the sucA gene, so that alpha-ketoglutaric acid dehydrogenase is weakened, and the decomposition way of alpha-ketoglutaric acid is weakened; the phosphoenolpyruvate carboxylase ppc is overexpressed, and the flow direction of phosphoenolpyruvate to oxaloacetic acid is enhanced; isocitrate dehydrogenase icd from escherichia coli is overexpressed, so that synthesis of a product is promoted; besides, pyruvate dehydrogenase derived from saccharomyces cerevisiae is introduced and coded by genes PDB1, PDA1 and LAT1, so that an important precursor, namely pyruvic acid, is promoted to flow to acetyl coenzyme A; the engineering strain with high yield of alpha-ketoglutaric acid is finally obtained, the yield of 75.1 g / L can be achieved in a 5L fermentation tank through a fed-batch fermentation method for 40 hours, and the conversion rate is 39.6%.

An E. coli bacterial diagnostic device comprises an outer body with a first chamber for fluid intake and a second chamber for a lateral flow test strip holder, featuring a results viewing window. An inner body, rotatable within the first chamber, includes a fluid receiving chamber and an opening for fluid passage. A filter located between the outer and inner bodies ensures fluid filtration. A lateral test strip holder, located in the second chamber, can move between a test position in which a portion of a lateral flow test strip located in the lateral test strip holder is positioned in the first chamber adjacent the filter and a second retracted position in which the lateral flow test strip is positioned in the second chamber.

The invention provides a blood microorganism-based autism prediction model and application thereof, the prediction model takes blood microorganisms as markers, and the detection rate or relative abundance of the blood microorganisms is reduced; the risk that the blood sample suffers from autism is predicted by increasing the detection rate of blood microorganisms II or enhancing the relative abundance; the first blood microorganisms comprise ochrobactrum, pseudoalteromonas sp.3J6, rhodococcus equi, parabacteroides dieldrii, trichoderma harzianum, enterobacter hormaechei, wolbachia, yersinia enterocolitica, treponema pallidum and Elizabeth mosquito-repellent bacteria; the blood microorganisms II comprise Klebsiella compacticola and bdellovibrio bacteriovorus. According to the method, the model is constructed based on the blood metagenome data of 1946 standard autism four families, the advantages of blood microorganisms are brought into full play, disease signals are sensitively and accurately captured, the method can be applied to clinical autism prediction, and early risk assessment and layering of diseases are achieved.

The application discloses a specific phosphorus-dissolving bacterial strain combination, a carrier for the strain combination and a co-cultivation method, and the strain combination is composed of Burkholderia cenocepacia, Burkholderia pyrrocinia, Enterobacter aerogenes and Bacillus subtilis, and the carrier is a mixture of discarded peanut shells and sugarcane residues. The application determines the dominant carrier suitable for the growth of the specific strain combination, meets the strain type and the number of living bacteria of the microbial agent product stipulated by the country, and effectively solves the problems of easy inactivation of the phosphorus-dissolving microbial strain in liquid, short preservation time and high transportation cost through the optimal cultivation process system of the specific phosphorus-dissolving microbial strain combination on the carrier. The strain activity and proliferation are maintained through the fermentation of the strain on the solid carrier, so as to meet the market demand for the phosphorus-dissolving microbial agent product.

The invention discloses an inorganic nano disinfectant and a preparation method thereof, and belongs to the technical field of nano materials and disinfection. The preparation method comprises the following steps: adding copper salt, zinc salt, silver salt and deionized water into a reaction kettle, and carrying out hydrothermal reaction to obtain a solution A; adding a surfactant and an alkaline pH regulator into the solution A, regulating the pH value of the solution, and carrying out heat preservation reaction to obtain a solution B; and adding an acidic pH regulator into the solution B to regulate the pH value of the solution, thereby obtaining the inorganic nano disinfectant. Microbial cell membranes and DNA / RNA are destroyed through metal ions, and the inactivation rates of H1N1 viruses, escherichia coli (ATCC 25922), staphylococcus aureus (ATCC 6538) and mites all reach 100%. Meanwhile, the pH is close to neutral, corrosion is avoided, and residual metal ions can be recycled through precipitation. According to the disinfectant prepared by the invention, low-concentration, broad-spectrum and long-acting disinfection of the disinfectant is realized by controllably synthesizing a nano-copper, zinc and silver composite system and combining pH regulation and surface modification technologies.

The invention discloses four kinds of endolysin SMLYS-1, SMLYS-2, SMLYS-3 and SMLYS-4 derived from salmonella prophage, and the application values of the four kinds of endolysin SMLYS-1, SMLYS-2, SMLYS-3 and SMLYS-4 are elaborated in detail. Four endolysin genes are seamlessly cloned into a pSumo-mut vector, and efficient expression is realized by utilizing an escherichia coli BL21 (Arctic-Express) system, so that the endolysin protein with remarkable antibacterial activity is successfully obtained. Experimental results show that the endolysin SMLYS-1, the endolysin SMLYS-2, the endolysin SMLYS-3 and the endolysin SMLYS-4 can be used for effectively killing salmonella isolates from various sources, and the endophysin SMLYS-1, the endolysin SMLYS-2, the endolysin SMLYS-3 and the endolysin SMLYS-4 have great potential as an anti-salmonella preparation and a salmonella infection treatment drug. The invention provides a new technical means for preventing and treating salmonella infection, and has important scientific significance and practical application value.

The application discloses application of a broad-spectrum type III esterase derived from Rhodococcus in phthalate ester pollution bioremediation, and overcomes the limitation of low degradation efficiency of a natural strain; through genetic engineering technology, the esterase 5359 gene is cloned into a Rhodococcus-E.coli shuttle vector pNV18 to construct a recombinant Rhodococcus engineering bacterium WT-pNV18-5359 overexpressing the esterase. Experimental results show that the engineering bacterium significantly improves the degradation performance: in single PAEs degradation test, the degradation rates of long-chain PAEs such as DEHP, DnOP and DiNP are respectively increased by 15.71%, 13.99% and 12.82% compared with the wild type; in a mixed PAEs system, the degradation of long-chain PAEs is obviously superior, and the engineering bacterium has good genetic stability and does not affect growth. Through genetic engineering to strengthen the application of known enzymes, efficient and stable PAEs pollution bioremediation is realized.

The application provides an organic carrier endo- rhizosphere growth promoting microbial agent for degraded grassland ecological restoration and a preparation method and application thereof, and belongs to the technical field of grassland ecological restoration and microbial agents. The organic carrier growth promoting microbial agent comprises four endo- rhizosphere growth promoting bacteria (PGPE), four rhizosphere growth promoting bacteria (PGPR) and an organic carrier; the PGPE comprises B. terrigena K4, B. subtilis 9-3-1, B. safensis 11-5-4 and Halomonas sp. L31, the PGPR comprises Serratia marcescens 5, Serratia marcescens 23, Kosakonia koreensis 11 and Enterobacter cloacae 24, and the organic carrier is carbon-based organic fertilizer, cattle and sheep manure organic fertilizer or biochar. The application of the organic carrier growth promoting microbial agent in degraded grassland can significantly improve the biomass and coverage of the plant community. The organic carrier growth promoting microbial agent can be used for the ecological restoration of degraded grassland.

The invention provides an intestinal flora composition for preventing or treating osteoporosis and application thereof, and relates to the technical field of biology. According to the invention, causal association analysis is carried out on whole genome heritable variation data and intestinal flora data of East Asian population through a Mendel randomization method, and the intestinal flora for preventing or treating osteoporosis is screened out; comprising acid amide bacteria enterobacter, bacillus haulis, kiwifruit bacteria, archaea extensa, streptococcus ricini and lysobacter pitermannii, and an accurate microbial intervention target is provided for prevention and intervention of osteoporosis. The intervention mode based on microbiomics has the advantages of noninvasiveness, high safety, good tolerance and the like, can be used for a long time, has no drug accumulation risk, and is especially suitable for early prevention and chronic management scenes of osteoporosis.

The invention discloses a composition, a kit and a detection method for detecting bacterial infection pathogens. The composition comprises at least one of a component A, a component B and a component C, the component A comprises nucleotide sequences as shown in SEQ ID NO: 1-3, and the component A is used for detecting bacteroides fragilis; the component B comprises nucleotide sequences as shown in SEQ ID NO: 4-6, and the component B is used for detecting citrobacter freundii; the component C comprises nucleotide sequences as shown in SEQ ID NO: 7-9, and the component C is used for detecting enterobacter aerogenes. By designing the upstream and downstream primers and the corresponding probes, the composition for detecting the bacterial infection pathogens can detect and distinguish at least one of bacteroides fragilis, citrobacter freundii and enterobacter aerogenes, is high in sensitivity, high in specificity and strong in anti-interference performance, improves the detection efficiency, shortens the detection period, reduces the detection cost, and is suitable for popularization and application. Good application prospects are realized.