210 results about "Bacteriocyte" patented technology

The invention discloses antibacterial poly (beta-amino ester) and a preparation method and application thereof, poly (beta-amino ester) macromolecules simultaneously have amino positive charges and fluorine-containing hydrophobic components, existence of the positive charges enables the poly (beta-amino ester) macromolecules to be more easily combined with negatively charged bacterial cell membranes and to be enriched, and the hydrophobic components can enable the poly (beta-amino ester) macromolecules to be inserted into cell membrane phospholipid bilayers, so that the antibacterial effect is improved. Therefore, bacteria are effectively killed, and drug resistance is not easily caused. The polymer has high antibacterial property and low hemolytic toxicity, can be self-assembled into nano particles, and can be combined with antibiotics in an antibiotic loading manner to improve the treatment effect. The compound can be synthesized through simple steps, the reaction condition is simple, the preparation cost, the raw material cost and the application cost are very low, and the compound has a very good prospect when being applied to medicines for treating or preventing diseases caused by bacteria.

The invention discloses a preparation method of photo-thermal-MMP dual-response matrix hydrogel and application of the photo-thermal-MMP dual-response matrix hydrogel in diabetic wound repair, and belongs to the technical field of biological medicine. According to the present invention, the Cur (at) ZIF-8 (at) MMPDA / dAMG composite hydrogel is composed of an amnion source photo-crosslinked matrix hydrogel, curcumin-loaded ZIF-8 nanoparticles and MMP2 peptide modified polydopamine, and the Cur (at) ZIF-8 (at) MMPDA / dAMG composite hydrogel is obtained; the ZIF-8 nanoparticles decline in an acid environment to release zinc ions, destroy bacterial cell membranes, enhance the permeability of a biological membrane and cooperatively kill drug-resistant bacteria in combination with a photothermal effect, Cur is loaded through ZIF-8 to form Cur-coated ZIF-8, then a Cur-coated ZIF-8-coated MMPDA / dAMG double-drug-loading system is constructed through an MMPDA medium, and a photothermal antibacterial, anti-inflammatory and regeneration-promoting multi-mode therapy is formed for a wound surface in the acid environment. Therefore, wound healing is accelerated.

The invention discloses a composite antibacterial preparation containing antibacterial peptide and traditional Chinese medicines as well as a preparation method and application of the composite antibacterial preparation, and belongs to the technical field of biological medicines. The antibacterial peptide provided by the invention is a transmembrane protein derived from bacteriophage, and the core function of the antibacterial peptide is that bacterial cell lysis is promoted by destroying a connection structure of a peptidoglycan layer and lipoprotein of a bacterial cell wall, so that an antibacterial effect is achieved. The amino acid sequence of the antibacterial peptide is shown as SEQ ID NO: 3, the antibacterial peptide is combined with traditional Chinese medicines to form a composite antibacterial preparation, and experiments prove that the composite antibacterial preparation has a relatively good antibacterial effect on gram-positive bacteria and gram-negative bacteria and can be applied to the medical field, such as surgical instrument disinfection and drug-resistant bacterial infection treatment; the field of daily chemicals, such as antibacterial hand sanitizers and wound dressings; in the field of agriculture, for example, animal feed additives for preventing and treating intestinal infection have a good market application prospect.

The present disclosure provides engineered bacterial cells having one or more genetic modifications that result in increased production of expression products, such as increased production of plasmids with reduced occurrence of plasmid concatemers or multimers. Also disclosed herein are expression systems for product manufacturing in media having reduced antibiotic concentration, as well as methods of making cells for use in the expression systems. The cells and expression systems increase the growth rate and production yields of biomolecules produced within the host bacterial host cells without the use of antibiotics, and can produce the product with little to no endotoxins present.

The invention relates to the technical field of protective films, and discloses a mobile phone protective film and a preparation method thereof. Modified graphene oxide is used as a filler, a modified waterborne polyurethane emulsion is used as a film forming substance, a flatting agent and a defoaming agent are used as auxiliary materials, a waterborne polyurethane coating is prepared, the surface of a PET base material is coated with the waterborne polyurethane coating, then drying is conducted, and the mobile phone protection film is obtained. A quaternary ammonium salt group and negative charges on a bacterial cell membrane generate electrostatic attraction, so that the original structure and function of the cell membrane are destroyed, and a bactericidal effect is achieved; silanol groups generated by hydrolysis of silane groups can react with hydroxyl groups and carboxyl groups on the surface of a PET base material, so that the interface bonding force between the coating and the base material is improved; nitrogen atoms in pyrrolidone groups form hydrogen bonds with hydroxyl groups and carboxyl groups on the surface of a base material, so that the bonding strength of the coating and the base material is further improved; the adamantyl group is grafted into the graphene oxide, so that the supporting effect of the graphene oxide on the waterborne polyurethane is enhanced, and the mechanical property of the mobile phone protective film is improved.

The invention discloses an intelligent quintuplet cooperative plasma self-purification robot long-term storage system and a self-adaptive disinfection control method. According to the system, cold plasma, ozone, chlorine dioxide, self-generated nitric oxide and a charge self-purification jump effect are fused, and a dynamic self-purification system with an electric field-gas field-chemical field-intelligent field-thermal field five-dimensional synergistic energy field is constructed. The robot adopts a three-section structural layout and a multi-mode self-adaptive propulsion mechanism, environmental parameters are sensed through AI, discharge power and oxidant release are intelligently regulated and controlled, and precise sterilization, toxicity reduction and mildew prevention in a multi-medium environment are achieved. The system can generate various high-energy active species containing. OH, O, NO, ClO, ONOO and the like, chain splitting decomposition and oxidation mineralization are carried out on mold spores, bacterial cells, aflatoxin and the like, the sterilization rate reaches 99.995%, and the toxin degradation rate exceeds 98%. The system has the characteristics of no residue, low energy consumption, long-acting self-maintenance and the like, is suitable for multiple scenes of grain storage, traditional Chinese medicinal materials, cold chains, farmland, public health and the like, and realizes an intelligent, continuous and chemical-additive-free green storage and dynamic purification system.

The invention relates to the field of biological environmental protection, in particular to a heterotrophic nitrification immobilized engineering bacterium for efficient denitrification and a preparation method and application thereof.According to the heterotrophic nitrification immobilized engineering bacterium for efficient denitrification and the preparation method and application of the heterotrophic nitrification immobilized engineering bacterium, polyethylene glycol-glucan two-aqueous-phase concentration and trehalose protection liquid are adopted for synergistic effect, the bottleneck of cell damage caused by a traditional flocculation method can be avoided, trehalose molecules can wrap bacterial cells, and the bacterial cells can be effectively degraded; the immobilized particles can resist osmotic pressure impact and pollutant invasion, the survival rate of thalli is higher than 95%, so that the immobilized particles always keep ultrahigh denitrifying enzyme activity in various sewage environments, honeycomb-shaped pores are formed in an ethyl cellulose matrix, a microenvironment with a high specific surface area is provided for thalli attachment, and the built-in nano zeolite continuously and slowly releases Cu < 2 + > and Zn < 2 + > trace elements, so that the immobilized particles can be recycled. A thallus metabolism enzyme system is synergistically activated, and the denitrification pathway function is enhanced; the chitosan-polydopamine outer coating layer strongly captures the nitrogen-containing pollutants, so that the removal efficiency of the nitrogen-containing pollutants is improved; through triple protection, the density of unit granular bacteria is up to 109 cells / cm, the service life is prolonged, and the denitrification performance is improved by more than 40%.

In various embodiments, provided herein are host cells, methods, and pharmaceutical compositions comprising gastrodin, wherein the gastrodin is produced by a genetically modified plant or plant cell, fungal cell, yeast cell, insect cell, or bacterial cell. In certain embodiments, the present disclosure provides methods and compositions for the production of gastrodin. In yet other embodiments, the present disclosure provides enhanced cells and methods for producing gastrodin.

Provided herein are methods for the production of a vector with a size of at least 16 kb from bacterial cells comprising the consecutive steps of a) obtaining bacterial cells comprising a vector with a size of at least 16 kb, comprising an inducible origin of replication, b) inoculating culture medium with the bacterial cells comprising the vector, c) culturing the bacterial cells in the culture medium, d) adding one or more inducers of said inducible origin of replication to the culture medium when the bacterial culture has reached an optical density at 600 nm (OD600) of at least 20, e) further culturing the bacterial cells in the culture medium, f) optionally separating the bacterial cells from the culture medium, and g) recovering the plasmid from the bacterial cells. Also provided herein are vectors with a size of at least 16 kb comprising an inducible origin of replication for use in such methods.

The invention discloses antibacterial coating liquid, a preparation method thereof and an implantable medical device. In preparation of the antibacterial coating liquid, firstly, polyvinyl alcohol and phytic acid are mixed and stirred to realize crosslinking, and then the mixture is mixed with tannic acid and an SBMA zwitterionic solution to prepare the coating liquid. The coating liquid can be loaded on the surface of a substrate through a simple method to prepare an antibacterial coating, and the coating has excellent adhesion performance and can be prevented from falling off in the use process. Due to the excellent hydrophilicity, the adhesion of bacteria, platelets and the like can be effectively reduced. Meanwhile, the phytic acid and cationic groups in the SBMA zwitterions are combined with bacterial cell membranes through electrostatic interaction, so that the bacterial structure is destroyed, and the antibacterial performance of the coating is further enhanced. In an in-vivo implantation experiment, the coating shows good biocompatibility.

This invention discloses a method for preparing and applying a photothermal nanoreagent targeting bacteria. This invention utilizes Ti3C2T... x Using MXene as a matrix, a photothermal nanoreagent MXene@PDA@Peptide (MPP) was constructed by sequentially modifying the surface of Ti3C2Tx MXene with polydopamine and grafting it with the peptide CAEKA, which has the function of recognizing bacteria. Under the recognition of the peptide CAEKA, the photothermal Ti3C2Tx MXene was targeted. x MXene nanosheets are guided to the surface of bacterial cells, achieving effective sterilization at a relatively low overall temperature of around 50°C (or achieving more efficient sterilization at the same overall temperature level, exhibiting superior sterilization performance compared to pure Ti3C2Tx MXene). This makes them particularly suitable for the preparation of therapeutic drugs for subcutaneous abscesses caused by methicillin-resistant Staphylococcus aureus (MRSA) infection.

This invention discloses a composite nanofiber membrane for immobilizing microorganisms to remediate diesel-contaminated water and its preparation method. Specifically, the composite nanofiber membrane is a thermoplastic polyurethane / nanohydroxyapatite composite nanofiber membrane, which not only possesses excellent biocompatibility and mechanical strength but is also non-toxic and harmless, offering considerable cost-effectiveness. Upon introduction into diesel-contaminated water, the composite nanofiber membrane first rapidly adsorbs diesel at the water / oil interface, preventing further diffusion and toxic effects on the aquatic environment. Subsequently, due to the additional adsorption sites provided by the nanoparticles on the membrane, a large number of free bacteria are adsorbed onto the membrane, enhancing the metabolic activity of bacterial cells and their resistance to the toxicity of stubborn compounds, while also strengthening the affinity between hydrophobic compounds and cells, thereby increasing the degradation rate of diesel hydrocarbons by microbial cells. This invention improves the remediation effect of diesel wastewater while expanding the application of composite nanofiber membranes in the field of water pollution treatment.

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.

Compositions of chitosan and one or more polyalcohols, such as mannitol and polyethylene glycol, and methods of use thereof, are provided. The disclosed compositions can deliver high concentrations of localized antimicrobials and metabolites to make infections more susceptible to antimicrobials. The disclosed compositions may be used to deliver biologically active agents to an infection at a site of trauma or surrounding an indwelling medical device, to treat an infection caused by persister bacterial cells, and to treat and / or prevent the formation of biofilm bacteria on an indwelling medical device or surrounding tissue.

The invention discloses a manganese-based layered hydroxide modified by gold nanoparticles and a preparation method thereof, and relates to the technical field of drug synthesis, and the key points of the technical scheme are as follows: the layered morphology of Mn-LDH is observed on the manganese-based layered hydroxide in a transmission electron microscope, and spherical AuNPs dispersed on the surface and edge of a laminate have a uniform particle size and a uniform particle size. EDS energy spectrum analysis finds that gold, manganese, magnesium, aluminum and carbon elements exist, the hydrated particle size is 312 nm, and the dispersity is good. The material can initiate an excellent photo-thermal effect under the irradiation of 808nm near-infrared light to generate active oxygen and hydroxyl radicals to destroy bacterial cell walls and cell membranes, and the antibacterial effect can reach 99%. In addition, the material can stimulate a local active immune function, promote T cell infiltration and realize active immune sterilization. The nano material shows a remarkable anti-infection effect in an in-vitro antibacterial experiment and an in-vivo osteomyelitis animal model experiment, and a new insight is provided for treating osteomyelitis caused by methicillin-resistant staphylococcus aureus.

The current disclosure relates to the present disclosure is directed to an inducible promoter system for use in a thermophilic bacterial cell. In another aspect, the disclosure is directed to a thermophilic host cell comprising the inducible promoter system described herein. In a further aspect, the disclosure is directed to a method of controlling gene expression in a thermophilic bacterium.

This invention relates to an antibacterial membrane-penetrating peptide and its applications. The amino acid sequence of the antibacterial membrane-penetrating peptide includes the sequence shown in SEQ ID NO.1 or a sequence with more than 70% homology to the sequence shown in SEQ ID NO.1. This invention screened and obtained a short peptide that specifically binds to the bacterial Hsp70s protein. It was found that this peptide binds to the Hsp70s protein through a traditional substrate-binding pocket, exhibiting an unusually high affinity for the protein in the DnaK-ATP state. The short peptide can inhibit Hsp70s protein activity to a certain extent, preventing it from aiding in the renaturation of denatured luciferase. Furthermore, while maintaining the integrity of the bacterial cell membrane, this short peptide has a superior ability to cross the bacterial cell membrane. The invention further discusses its application potential in the preparation of antibacterial drugs and antibiotic adjuvants, providing new ideas for solving current problems such as bacterial resistance and the difficulty in discovering new antibiotics.

The application belongs to the technical field of non-antibiotic compounds as bacteriostatic agents, and discloses an application of a known non-antibiotic compound, cladrabine, in inhibiting the growth of multi-drug resistant Klebsiella pneumoniae. The application finds that cladrabine can inhibit the growth of multi-drug resistant Klebsiella pneumoniae, and the minimum bacteriostatic concentration reaches 64 mg / L. Further exploration of the bacteriostatic mechanism finds that after exposure to cladrabine, the permeability of the bacterial cell membrane is enhanced, and the macromolecular substances (nucleic acids and proteins) in the cell are excreted, causing the integrity of the bacterial cell membrane to be destroyed, and further causing the death of Klebsiella pneumoniae. The application proposes that cladrabine can destroy the cell membrane of bacteria, change the permeability of the cell membrane, has a good inhibitory effect on multi-drug resistant Klebsiella pneumoniae, and can be further applied to the preparation of related drugs.

The invention relates to the technical field of silk modification, in particular to titanium dioxide modified silk and a preparation method thereof.The titanium dioxide modified silk is formed by treating silk through titanium dioxide modification liquid, and the titanium dioxide modification liquid comprises nanometer titanium dioxide, a dispersing agent, a cross-linking agent, a functional auxiliary, composite nanoparticles and deionized water; the coating comprises the following components in parts by mass: 5-15 parts of nano titanium dioxide, 1-5 parts of a dispersing agent, 2-8 parts of a cross-linking agent, 0.5-3 parts of a functional auxiliary agent, 1-4 parts of composite nanoparticles and 68-90 parts of deionized water. According to the titanium dioxide modified silk and the preparation method thereof, a multi-stage antibacterial system is formed through a functional auxiliary agent and composite nanoparticles, chitosan quaternary ammonium salt destroys bacterial cell membranes to achieve rapid bacteriostasis, nano-silver achieves long-acting sterilization by means of the slow release effect of metal ions, and nano-titanium dioxide decomposes bacterial remains through photocatalysis; the antibacterial rate on escherichia coli and staphylococcus aureus is stable, and the problems that a traditional single antibacterial agent is prone to generating drug resistance and short in time effect are solved.

This invention discloses a composite antibacterial and oleophobic paper film and its preparation method, belonging to the technical field of food packaging materials. The preparation method provided by this invention uses bacterial cellulose as a base material, adds plasticizers and crosslinking agents, stirs and disperses them, then combines silane-modified starch oleophobic agent, phytic acid, nano-titanium dioxide, and surfactants, mixes them evenly, and obtains the finished product through suction filtration. This method uses bio-based raw materials throughout, discarding difficult-to-degrade harmful components, and the product is naturally biodegradable, solving the waste pollution problem at its source. Phytic acid, through chelating metal ions, destroying bacterial cell membranes, and photocatalytic generation of reactive oxygen species by nano-titanium dioxide, synergistically inhibits bacteria, achieving an antibacterial rate close to 100%. Silane-modified starch with methyl hydrophobic modification combined with the micro-nano rough structure of titanium dioxide significantly improves oleophobic and hydrophobic properties. The composite antibacterial and oleophobic paper film prepared by this method combines biodegradability, high-efficiency antibacterial properties, and excellent oleophobicity, making it suitable for industrial production and food packaging applications.

A microbial culture tank (10) comprises: a riser tank (11) having a structure for raising a culture liquid (S) that cultures methane-producing bacteria that generate methane (M); a downcomer tank (12) having a structure for lowering the culture liquid (S) overflowing from the riser tank (11); and a recovery section (13) for recovering methane (M) released from the culture liquid (S) in the riser tank (11) and the downcomer tank (12).

The disclosure relates to the field of specialty chemicals and methods for their synthesis. In embodiments, the disclosure provides viable bacterial cells which comprise heterologous dual 3-hydroxy-acyl-ACP dehydratase / isomerases, etc. The disclosure further provides monounsaturated fatty acid derivative molecules produced by the viable bacterial cells which are non-native to the bacterial cells. The disclosure further provides methods for the preparation and production of non-native monounsaturated fatty acid derivative molecules such as e.g., an ω3-monounsaturated fatty acid derivative, an ω5-monounsaturated fatty acid derivative, an ω9-monounsaturated fatty acid derivative, an ω11-monounsaturated fatty acid fatty acid derivative, etc.

The invention belongs to the technical field of biology, and discloses virus lysozyme from a deep sea cold spring as well as a preparation method and application of the virus lysozyme. The virus lysozyme provided by the invention comprises amino acid fragments of which the sequences are as shown in one or more of SEQ ID NO: 1-7. The virus lysozyme is derived from a deep sea cold spring virus, the sequence and the structure of the virus lysozyme can keep structural stability and activity in extreme environments such as low temperature and high pressure, and the virus lysozyme has relatively good bacterial cell wall lysis capability and bacteriostatic action; the method has important significance on research and development of bacteriostatic agents under special ecological or technological conditions such as low-temperature food preservation, biological processing and ocean engineering.

The present invention belongs to the technical field of photosensitizers, and in particular to a kind of aggregation-induced luminescence probe design, synthesis and sterilization application based on the metabolic anchoring live bacteria strategy of bioorthogonal reaction.The aggregation-induced luminescence compound of the present invention (aggregation-induced luminescence probe) is typical D π π A structure, using triphenylamine structural unit as the electron donor spacer group in molecular system, to prevent π π from piling up, using thiophene ring and carbon-carbon double bond as electron donor and π bridge, nitro unit as electron acceptor, the strong push-pull effect of overall formation electron, finally, also connected with the important synthetic raw material D-amino acid (D Ala) of bacterial cell wall.The aggregation-induced luminescence compound prepared by the present invention has long fluorescence lifetime, and fluorescence intensity is large, and a large amount of reactive oxygen can be produced after illumination to effectively kill live bacteria, and can be absorbed and utilized by bacteria by metabolism, to achieve the difference detection of live and dead bacteria.

The invention discloses a method for killing bovine herpesvirus by sodium chloride aerosol. The method comprises the following steps: (1) preparing sodium chloride aerosol of which the average particle size is 800nm and the particle size distribution is between 500nm and 8mu m, in the specific preparation process, respectively introducing a saturated sodium chloride aqueous solution and absolute ethyl alcohol into dry airflow of a spray dryer according to a volume ratio of 1: 1, and drying by the spray dryer to prepare the sodium chloride aerosol; and (2) the prepared sodium chloride aerosol is used as a bovine herpes virus killing agent to kill bovine herpes viruses, and in the virus killing process, the dosage is 10-60 mg, and the killing time is 10-30 s. The sodium chloride aerosol has the advantages that the sodium chloride aerosol has special antivirus efficacy in a specific dosage and time range, a high-concentration sodium chloride solution can dehydrate bacterial cells and destroy cell membrane structures of the bacterial cells through osmotic pressure difference to cause growth inhibition or death of bacteria, and especially 100% of bovine herpes viruses (BHV-1) can be killed in a very short time with a small dosage of sodium chloride aerosol.

The present disclosure provides an engineered nucleic acid sequence comprising a gene cassette, the gene cassette comprising one or more regulator genes, the regulator genes including an iadR gene, and at least three catabolic pathway genes downstream from the one or more regulator genes, the at least three catabolic pathway genes including an iadC gene, an iadD gene, and an iadE gene, wherein the engineered nucleic acid sequence is free of an iadA gene and iadB gene. The disclosure also provides bacteria cells comprising the engineered nucleic acid sequence, wherein the bacteria cell is capable of degrading indole-3-acetic acid. Methods for degrading auxin, controlling auxin, and promoting plant growth and root development are provided, comprising providing the bacteria cell and allowing the bacteria cell to interact with roots of a plant.

The application belongs to the technical field of biological medicine, and provides a ciprofloxacin derivative, a preparation method and application thereof. The ciprofloxacin derivative provided by the application has a structure shown in formula I, a positively charged electrostatic effect sequence (an amino acid part) is connected to a lipid part, then is conjugated with ciprofloxacin through a linker, and a series of amphipathic ciprofloxacin derivatives are formed. The positively charged electrostatic effect sequence can enhance the interaction with a negatively charged bacterial cell membrane through electrostatic action, then the lipid part can be inserted into a phospholipid bilayer of the bacterial cell membrane, leading to the integrity of the bacterial cell membrane being destroyed, the ciprofloxacin derivative entering the cell, and finally leading to the leakage of the bacterial cell content, the breakage of the bacterial chromosome and the death of the bacterial cell. The amphipathic ciprofloxacin derivative of the application simulates the amphipathic structure and membrane destruction mechanism of an antibacterial peptide, so that the ciprofloxacin derivative exhibits a unique advantage of not being prone to drug resistance.

The invention discloses an antibacterial healing-promoting hydrocolloid wound surface auxiliary material and a preparation method thereof, and the antibacterial healing-promoting hydrocolloid wound surface auxiliary material comprises the following components by mass: 30-50 parts of a hydrocolloid matrix; 5 to 12 parts of a modified chitosan-graphene composite antibacterial agent; 3-8 parts of plant source healing promoting active peptide; 4 to 10 parts of a poly gamma-glutamic acid grafted hyaluronic acid moisturizing synergist; 2-6 parts of a plasticizer; 1-4 parts of an adhesion regulator; 0.1 to 0.5 part of a preservative; 15 to 30 parts of deionized water; the antibacterial performance is excellent, the modified chitosan-graphene composite antibacterial agent is adopted, the antibacterial activity of chitosan is enhanced through quaternization modification, then chitosan is compounded with graphene, on one hand, the water solubility and the antibacterial activity of chitosan are enhanced, on the other hand, the high specific surface area and the charge effect of graphene are utilized, and the antibacterial performance of chitosan is improved. The damage capability of the antibacterial agent to bacterial cell membranes is further improved, broad-spectrum and efficient antibacterial effects are achieved, the risk of drug resistance is avoided, and the biological safety is high.

The invention discloses Japanese eel antibacterial peptide Ajaponin and application thereof, the Japanese eel antibacterial peptide Ajaponin is composed of 21 amino acids, the molecular weight is 2693.29 Dalton, the molecular weight contains 7 positively charged amino acid residues, the hydrophobicity is 0.316, the isoelectric point is 11.45, the Japanese eel antibacterial peptide Ajaponin is a novel cationic short peptide, has the advantages of good water solubility, high antibacterial activity, low toxicity and the like, is composed of limited amino acid residues, and can be used as a novel cationic short peptide. The structure is compact, synthesis and purification are easy, and large-scale production and application are facilitated; and the amino acid residues containing a plurality of positive charges are beneficial to interaction with negative charges of bacterial cell membranes and destroy the integrity of the membranes, so that the effects of rapidly inhibiting and killing bacteria are achieved.

An object is to provide a joint function-improving composition which is useful for prevention or treatment of various arthropathies such as osteoarthritis including knee osteoarthritis as a typical example and rheumatoid arthritis because the composition has an action of promoting growth of chondrocytes and an action of suppressing the production of an inflammation factor, a cartilage matrix degradation factor, a pain factor or a neuronal outgrowth factor by synoviocytes and to provide a joint function-improving product containing the composition such as a food or a drink, feed and a medicine. A joint function-improving composition containing bacterial cells and / or a culture of a bacterium belonging to genera Lactobacillus, Lactococcus, Streptococcus or Bifidobacterium and a joint function-improving agent, a joint function-improving food or drink, a joint function-improving nutritional composition, joint function-improving feed or a joint function-improving pharmaceutical agent which is characterized by containing the joint function-improving composition.