31 results about "Mycobacterium smegmatis" patented technology

The invention provides recombinant escherichia coli with high yield of ergothioneine and a method for preparing ergothioneine, the recombinant escherichia coli co-expresses ergothioneine anabolic enzymes Egt1 and Egt2, the methyltransferase structural domain of the Egt1 is derived from trichoderma reesei, mycobacterium smegmatis EgtD or rhizopus nigricans, and the methyltransferase structural domain of the Egt2 is derived from the trichoderma reesei, the mycobacterium smegmatis EgtD or the rhizopus nigricans. The histidine sulfoxide synthase structural domain is derived from trichoderma reesei, schizosaccharomyces pombe or rhizopus nigricans, and the Egt2 is derived from claviceps purpurea, neurospora crassa or aspergillus niger. After the recombinant escherichia coli obtained by screening is cultured for 68 hours in a 5L fermentation tank, the yield of ergothioneine can reach 5g / L or above; wherein after recombinant escherichia coli co-expressing Egt1 enzyme (the structural domain of methyltransferase is derived from mycobacterium smegmatis EgtD, and the structural domain of histidine sulfoxide synthase is derived from trichoderma reesei) and Egt2 enzyme (derived from neurospora crassa) are cultured in a 5L fermentation tank for 68 hours, the yield of ergothioneine can reach 8.7 g / L, and the production intensity reaches 127.9 mg / (L.h).

The invention relates to a photoactivated carbonyl manganese (I) complex and a preparation method and application thereof in antibiosis. The manganese (I) complex has a good photoactivation antibacterial effect. Specifically, the manganese carbonyl (I) complex can be photoactivated to release carbon monoxide and ligands under the irradiation of white light. By detecting MIC90 of the photoactivated carbonyl manganese (I) complex to different bacteria, the result shows that the photoactivated carbonyl manganese (I) complex has a better antibacterial effect on mycobacterium smegmatis.

Provided herein are Mycobacterium smegmatis porin nanopores, systems that comprise these nanopores, and methods of using and making these nanopores. Such nanopores may be wild-type MspA porins, mutant MspA porins, wild-type MspA paralog porins, wild-type MspA homolog porins, mutant MspA paralog porins, mutant MspA homolog porins, or single-chain Msp porins. Also provided are bacterial strains capable of inducible Msp porin expression.

The invention discloses a recombinant rMS:: MPT64 and an application thereof. The recombinant rMS:: MPT64 is prepared by transfecting mycobacterium smegmatis by a recombinant vector for expressing an MPT64 gene. According to the present invention, the MPT64 gene is integrated into Mycobacterium smegmatis (MS) to construct the recombinant MS (rMS:: MPT64) for expressing the MPT64, and the recombinant MS (rMS:: MPT64) has excellent immunogenicity and excellent anti-tuberculosis effect when being used in the tuberculosis vaccine.

This article provides information on mutant single-stranded smegma mycobacterium porin (Msp) and its applications.

This invention provides a method for constructing a high-yield ergothionein-producing Bacillus amyloliquefaciens engineered strain and its application. The engineered strain uses the food-grade safe strain Bacillus amyloliquefaciens HZ12 as the starting strain. Through genetic engineering, a key enzyme gene for ergothionein biosynthesis is heterologously expressed in Bacillus amyloliquefaciens. An RBS co-expression strategy is employed to express the mutant gene NcEgt1 derived from Neurospora crassa. Y174F / E51A Co-expression of the EgtE gene derived from *Mycobacterium smegmatis* successfully achieved heterologous synthesis of ergothioneine in *Bacillus amyloliquefaciens*. Under these conditions, the yield of ergothioneine reached 402.68 mg / L, marking the achievement of ergothioneine production in *Bacillus amyloliquefaciens* from scratch. Subsequently, through chassis strain modification, the yield of ergothioneine was further increased to 690.43 mg / L.

Antimicrobial peptides (AMPs), small compounds that often exhibit broad spectrum antimicrobial activity, are garnering interest as potential therapeutics against antibiotic-resistant bacterial pathogens. Development of new AMPs is arduous due to the practical limitations of classical protein-based discovery approaches. A high throughput bioinformatics approach is described which is able to confirm identification of known AMPs from the North American bullfrog (Rana (Lithobates) castebeiana) genome, and a bioinformatics approach is used to develop new AMPs, as described herein as SEQ ID NOs: 1-178. The described AMPs exhibit antimicrobial activity against Mycobacterium smegmatis via microtitre broth dilution assays, indicating broader efficacy.

The application discloses a methyl bacillus subtilis sulfoxide synthase MpEgtB mutant and application thereof, and belongs to the technical field of bioengineering. The application provides a methyl bacillus subutilis-derived sulfoxide synthase MpEgtB mutant capable of efficiently preparing ergothioneine and a modification method of the mutant, and the mutant protein is used to catalyze histidine trimethyl inner salt, L-Cys is used as a sulfur donor to directly convert the histidine trimethyl inner salt into histidine trimethyl inner salt-based cysteine sulfoxide, and the obtained mutant is coupled with Mycobacterium smegmatis-derived MsEgtD and MsEgtE to prepare L-EGT by using L-His and L-Met as substrates. The optimal mutant strain is used as a biological catalyst to perform whole-cell conversion, a continuous feeding strategy is adopted in a 5L fermenter, and the conversion is performed for 48h, so that the yield of L-EGT reaches 8.32g / L. The production process is simple, has few impurities, and has an important industrial application prospect.

The present invention relates to a photoactivated manganese (I) carbonyl complex, its preparation method, and its use in antibacterial applications. The manganese (I) complex exhibits significant photoactivated antibacterial effects. Specifically, under white light irradiation, the manganese (I) carbonyl complex can be photoactivated to release carbon monoxide and a ligand. Testing of the MIC90 values ​​of the photoactivated manganese (I) carbonyl complex against various bacteria revealed that the complex exhibited significant antibacterial effects against Mycobacterium smegmatis.

Provided herein are mutant single-chain Mycobacterium smegmatis porin (Msp) and uses thereof.

The invention relates to a mycobacterium abscessus and marine mycobacterium vaccine and a preparation method thereof, the mycobacterium abscessus and marine mycobacterium vaccine comprises a recombinant plasmid based on an antigen protein gene, the recombinant plasmid is used for stably expressing cell wall antigen protein, and the recombinant plasmid is used for stably expressing cell wall antigen protein. The recombinant plasmid sequentially contains a resistance screening gene Kan, an escherichia coli replicon oriE, a promoter hsp60, an antigen protein gene MMAR1296 and a gene tag Flag-tag in the clockwise direction, wherein the DNA (deoxyribonucleic acid) sequence of the promoter hsp60 is as shown in SEQ ID No.1; the recombinant plasmid sequentially contains a resistance screening gene Kan, an escherichia coli replicon oriE, a promoter hsp60, an antigen protein gene MMAR1296 and a gene tag Flag-tag in the clockwise direction; the sequence of the antigen protein gene MMAR1296 is as shown in SEQ ID No. 2; and the DNA (Deoxyribose Nucleic Acid) sequence of the gene tag Flag-tag is as shown in SEQ ID No. 3. According to the invention, cell wall antigen protein MMAR1296 from marine mycobacterium is displayed on the surface of a mycobacterium smegmatis Msmeg vaccine carrier without any toxicity, a recombinant strain and a vaccine thereof are constructed, and subcellular component separation and western-blot experiments prove that the antigen protein MMAR1296 is successfully displayed on the surface of mycobacterium smegmatis MC2155; balb / c mouse in-vivo experiments prove that the immune effect of the recombinant mycobacterium smegmatis vaccine with the MMAR1296 antigen protein displayed on the surface is far superior to that of a bacillus calmette guerin vaccine BCG.

The invention discloses application of a caragana crude extract and an n-butanol layer extract in antituberculous activity and preparation methods of the caragana crude extract and the n-butanol layer extract, and the preparation method of the caragana crude extract comprises the following steps: weighing dried and crushed caragana roots, adding 90% absolute ethyl alcohol with the same volume as the caragana roots, extracting by adopting a heating reflux extraction method, and concentrating under reduced pressure to obtain the caragana crude extract. Sequentially extracting with petroleum ether, dichloromethane and n-butyl alcohol to obtain caragana petroleum ether layer extract, dichloromethane layer extract and n-butyl alcohol layer extract; tests prove that the caragana crude extract and the caragana n-butyl alcohol layer extract have remarkable bacteriostatic activity on mycobacterium smegmatis, have a strong bacteriostatic effect on a mycobacterium tuberculosis standard strain H37Rv (ATCC27294) and have certain bacteriostatic activity on a multidrug-resistant tubercle bacillus strain Mtb706, and by means of activity-oriented extraction process optimization, the content of the caragana n-butyl alcohol layer extract is greatly improved. The screening range of the antituberculous active ingredients in the caragana roots is effectively narrowed, and a key foundation is laid for the subsequent separation and purification of the active ingredients and the research on the action mechanism.

The invention discloses application of an STX6 gene as a target spot in prevention and treatment of tuberculosis, the survival of mycobacterium bovis, mycobacterium tuberculosis, BCG and mycobacterium smegmatis in host cells can be remarkably inhibited by knocking out or knocking down the expression of the STX6 gene, the host cell death induced by the mycobacterium bovis and the mycobacterium tuberculosis is inhibited, and the normal proliferation of the host cells is not influenced. Meanwhile, the STX6 is highly conserved in mammals, so that the STX6 can be widely applied to prevention and treatment of tuberculosis caused by humans and animals, can also be used as a target for gene editing animal design, is applied to genetic therapy and disease-resistant breeding, and has rich application and economic values.

A method for endogenously extracting a Mycobacterium smegmatis protein nanocage is provided. The method includes the following steps: introducing a recombinant plasmid containing a CFP29 gene and a 1×Flag affinity tag into a Mycobacterium smegmatis strain to obtain a recombinant Mycobacterium smegmatis strain; extracting a total protein solution of the recombinant Mycobacterium smegmatis strain, and subjecting the total protein solution of the recombinant Mycobacterium smegmatis strain to Flag tag affinity column chromatography purification to obtain a crude extract of the Mycobacterium smegmatis protein nanocage; and subjecting the crude extract of the Mycobacterium smegmatis protein nanocage to gel exclusion chromatography purification to obtain a pure product of the Mycobacterium smegmatis protein nanocage. The method is simple to operate and convenient to implement during extraction and purification, and an obtained Mycobacterium smegmatis background protein nanocage has a high yield, excellent purity, and stable properties.

The invention discloses a nucleoside antibiotic with anti-mycobacterium tuberculosis activity and a preparation method and application thereof. The nucleoside antibiotic is muramycin D9 which is extracted and separated from fermentation liquor of streptomyces sp. NRRL 30475, the molecular formula of the nucleoside antibiotic is C38H61N11O15, and the nucleoside antibiotic is a muramycin compound which is obtained by dehydrating and cyclizing valine at the terminal of a peptide chain and non-protein source amino acid epicpremycine imine for the first time. An in-vitro anti-mycobacterium tuberculosis activity research shows that the nucleoside compound provided by the invention has very strong antibacterial activity on mycobacterium smegmatis and is expected to be developed into a novel anti-mycobacterium tuberculosis medicine.

Provided herein are mutant single-chain Mycobacterium smegmatis porin (Msp) and uses thereof.

The invention discloses a glutamate decarboxylase mutant and application thereof, and belongs to the technical field of biology. Glutamic acid decarboxylase BGAD from escherichia coli and a glutamic acid decarboxylase mutant MsGAD obtained by mutating glutamic acid decarboxylase from mycobacterium smegmatis are used for catalyzing L-glutamic acid to synthesize gamma-aminobutyric acid, and high-purity and high-yield gamma-aminobutyric acid can be obtained; in the catalytic reaction, hydrochloric acid or sulfuric acid does not need to be additionally added to regulate pH, almost no L-glutamic acid is left after catalysis is finished, the yield reaches 98% or above, and the yield of gamma-aminobutyric acid can reach 605g / L or above; meanwhile, the production process provided by the invention is simple and easy to operate, can be applied to large-scale industrial production, and has a good application prospect.

Antimicrobial peptides (AMPs), small compounds that often exhibit broad spectrum antimicrobial activity, are garnering interest as potential therapeutics against antibiotic-resistant bacterial pathogens. Development of new AMPs is arduous due to the practical limitations of classical protein-based discovery approaches. A high throughput bioinformatics approach is described which is able to confirm identification of known AMPs from the North American bullfrog (Rana (Lithobates) catesbeiana) genome, and a bioinformatics approach is used to develop new AMPs. The described AMPs exhibit antimicrobial activity against Mycobacterium smegmatis via microtitre broth dilution assays, indicating broader efficacy.

The invention describes a recombinant Mycobacterium strain such as M. smegmatis that is recombinantly converted to express the M. tb complex ESX protein expression system, e.g. M. tb complex ESX-1 protein expression system. The recombinant strain exports virulence effector proteins (such as EspA, EspB, EspC, EsxA or EsxB) similar to M. tb, when administered to a subject, and is therefore useful as a potential tuberculosis vaccine candidate. The recombinant strain is non-pathogenic and the vaccinated subject does not give a false positive result when tested with any standard tuberculosis diagnostic test e.g. CCT, as the recombinant strain does not sensitize the vaccinated host to M. tb antigens or protein derivate of M. bovis.

The invention discloses a mycobacterium protein with an anti-inflammatory effect as well as preparation and application of the mycobacterium protein. The invention discloses a mycobacterium protein Rv2723 with an amino acid sequence as shown in SEQ ID NO.1. The protein of the sequence is reported for the first time. Activity studies show that the Rv2723 recombinant protein can significantly inhibit the expression of LPS-induced macrophage inflammatory factors, the Rv2723 overexpression can effectively inhibit the expression of Mycobacterium smegmatis-induced macrophage inflammatory factors, and the Rv2723 overexpression can down-regulate the expression of Mycobacterium smegmatis-infected mouse serum inflammatory factors IL-6. In addition, the Rv2723 does not generate excessive immunological rejection. Therefore, the mycobacterium protein Rv2723 with the amino acid sequence as shown in SEQ ID NO.1, the coding gene of the mycobacterium protein Rv2723, and a recombinant vector, recombinant bacteria or recombinant cells containing the coding gene have the prospect of being developed into anti-inflammatory drugs.

The invention relates to an exosome-coated phosphorus-containing dendrimer / antibacterial peptide composite material as well as preparation and application thereof. The exosome-coated phosphorus-containing dendrimer / antibacterial peptide composite material comprises a phosphorus-containing dendrimer, a peptide and an exosome. The preparation method disclosed by the invention has the characteristics of simplicity, high reaction process controllability, easiness in operation and separation and the like, the intracellular transmission efficiency and antibacterial activity of nisin can be improved, efficient removal of mycobacterium smegmatis is realized by virtue of an exosome-mediated host targeting function, and the preparation method has a good development prospect and application value in treatment of pulmonary tuberculosis patients.

This invention discloses NmrAL2_Bovine The application of genes as targets in the prevention and control of bovine tuberculosis, including knockout or knockdown. NmrAL2_ Bovine The gene can significantly inhibit the survival of Mycobacterium bovis, Mycobacterium tuberculosis, Mycobacterium bovis BCG, and Mycobacterium smegmae in host cells without affecting the normal proliferation of host cells. Therefore, NmrAL2_Bovine Gene inhibitors can be used to prepare drugs for the prevention and treatment of bovine tuberculosis. NmrAL2_Bovine Genes can also be used as targets in the design of transgenic cattle for breeding against bovine tuberculosis or for genetic therapy research.

The utility model relates to the technical field of bacteria shaking tubes, and discloses a mycobacterium smegmatis bacteria shaking tube. The mycobacterium smegmatis shaking tube comprises a test tube main body, the stirring plate is positioned in the test tube main body and is used for improving the shaking efficiency of mycobacterium smegmatis; a cover is arranged at the top of the test tube body and connected with the top of the test tube body in a clamping mode, a plug is arranged in the cover, the top of the plug and the cover are integrally formed, and a rotating rod rotates on a supporting block through a connecting block. The stirring plate rotates to stir the mycobacterium smegmatis precipitated at the bottom of the test tube main body, so that the condition that the mycobacterium smegmatis is precipitated when the mycobacterium smegmatis is centrifugally shaken through the test tube main body is prevented, and meanwhile, the mycobacterium smegmatis is stirred through the stirring plate, so that the shaking efficiency of the mycobacterium smegmatis is improved; therefore, the working efficiency is improved, and the practicability of the device is embodied.

The invention belongs to the field of gene engineering, particularly relates to a gene engineering strain with high yield of ergothioneine, and further discloses a construction method of the gene engineering strain and application of the strain in synthesis of ergothioneine. According to the genetic engineering strain, escherichia coli is used as a chassis cell, pETDuet-1 is used as an expression vector, a coding gene of histidine methyltransferase NcEgt1-1 subjected to truncation, site-specific mutagenesis and combinatorial mutagenesis, a coding gene of sulfoxide synthase CtEgtB from Chlorbacillus thermophilus subjected to site-specific mutagenesis and a coding gene of histidine methyltransferase NcEgt1-1 subjected to site-specific mutagenesis are heterologously expressed in the escherichia coli, and pETDuet-1 is used as an expression vector. The invention relates to a gene engineering bacterium containing non-natural ergothioneine and a coding gene of PLP C-S lyase MsEgtE from Mycobacterium smegmatis, so that the gene engineering bacterium containing the non-natural ergothioneine synthesis route is constructed.

The present invention belongs to the field of organic synthesis technology and specifically provides a photoactive ruthenium complex and a preparation method thereof. The photoactive ruthenium complex provided by the present invention not only decomposes and releases isoniazid under light but also generates singlet oxygen under light excitation, exhibiting dual antibacterial effects, including significant antibacterial effects against Mycobacterium smegmatis, and can be used to treat tuberculosis infection.

This invention belongs to the field of microbiology, specifically relating to the application of albizophenolic compounds. These compounds inhibit pathogenic bacteria such as Salmonella, Mycobacterium smegmatis, Enterococcus faecalis, and Staphylococcus aureus, and inhibit the growth of human lung cancer cells and human breast cancer cells, exhibiting bactericidal and anticancer activities. They are suitable for developing products for everyday household use, medical care, and animal husbandry, with broad prospects for industrial application.

The invention discloses application of a PAPSS2 gene as a target spot in prevention and treatment of tuberculosis, the PAPSS2 gene is knocked out or knocked down, so that survival of mycobacterium bovis, mycobacterium tuberculosis, BCG and mycobacterium smegmatis in host cells can be remarkably inhibited, and normal proliferation of the host cells is not affected. Meanwhile, the PAPSS2 is highly conserved in mammals, so that the PAPSS2 can be widely applied to prevention and treatment of tuberculosis caused by humans and animals, can also be used as a target for gene editing animal design, is applied to genetic therapy and disease-resistant breeding, and has rich application and economic values.

This invention discloses a novel application of the pyridopyrimidine compound AK-968 / 11492032 as an inhibitor of mycobacterial thiol disulfide reductase and in anti-mycobacterial drugs. Through extensive experimental screening, this invention has demonstrated that compound AK-968 / 11492032 can bind to mycobacterial thiol disulfide reductase and reduce its enzyme activity. Furthermore, this compound exhibits a significant antibacterial effect against *Mycobacterium smegmae* with a MIC of 2 μg / ml. Therefore, AK-968 / 11492032 can serve as an inhibitor of mycobacterial thiol disulfide reductase and holds promise for development into a novel anti-pathogenic mycobacterial drug, possessing significant application value.

The invention belongs to the technical field of biological medicine, provides a method for constructing a biosafety mouse bone tuberculosis model based on mycobacterium smegmatis, and evaluates that under the condition of a standard biosafety level (BSL)-1, the mycobacterium smegmatis induces local and disseminated bone infection through three infection pathways, and the bone tuberculosis model has the advantages that the bone tuberculosis is induced by the mycobacterium smegmatis through three infection pathways; results show that the mouse model for intracentral injection administration of the three infection pathways is closer to the latent progress of human bone tuberculosis. The mouse model based on the mycobacterium smegmatis provides a simple and reliable platform related to immunopathology for exploring host-pathogen dynamics, immunologically-driven bone destruction and early treatment tests.