31 results about "Erythromycin resistance" patented technology

The invention relates to the application of a gene engineering technology in increasing an antibiotic component, in particular to a gene series technology for increasing the main component content ofgene engineering isovaleryl selectomycin. The gene series technology comprises the following steps: connecting ist genes which are closely related to selectomycin isovaleryl acylation in Beta selectomycin gene engineering bacteria in series; increasing the bacterial isovaleryl acylation generating capability by increasing gene dosage; using a promoter erythrocin resistance gene erm promoter sequence with strong promotion activity to replace the original ist gene promoter sequence so as to increase the expression of the series ist genes, and improve the proportion of isovaleryl selectomycin main components of the gene engineering bacteria from a headstream.

The present invention relates to a high-throughput detection chip for drug resistance gene of bacteria, and an application thereof. The detection chip comprises 117 gene probes, the drug resistance gene probes are selected from 17 categories of drug resistance genes, which comprise extended spectrum beta-lactamase, cephalosporinase, carbapenemase, integrase gene, tetracycline resistance gene, aminoglycoside resistance gene, disinfectant resistance gene, erythromycin resistance gene, macrolide efflux gene, vancomycin resistance gene, multidrug resistance efflux pump gene, mupirocin resistance gene, sulfanilamide resistance gene, tylosin resistance gene, fluoroquinolone resistance gene, chloramphenicol acetyltransferase and commonly-used genetic engineering vector resistance gene. The chip is adopted for detecting the resistance gene of the pathogenic bacteria. The chip is characterized in that: the chip comprises (1) 117-oligonucleotide probe composition and quality control probes of 17 categories of the drug resistance genes; (2) probe arrays, wherein the oligonucleotide probes are solidified on the vector material through arm molecules to form the probe arrays.

The invention pertains to the field of medical technology and relates to engineering bacteria directly producing tobramycin and the application thereof, which mainly damages carboxamide transferase gene in bacteria produced by the tobramycin, therefore the strain does not produce carboxamide tobramycin any more but tobramycin. The invention, by the method of deleting inactivation within the frame, breaks tacA gene in Streptomyces tenebrarius, comprising the composition of the tacA gene breaking plasmid, the breaking of the transformation of plasmid pSPU303 into Streptomyces tenebrarius H6, the screening of double exchange strains, the detection of fermentation products and the identification of new compositions. The method of deleting inactivation within the frame respectively provides two segments with the upper reach molecular weight and the lower reach molecular weight of the tacA gene not less than 500bp for the PCR, both segments are connected to pIJ2925 simultaneously, one end of the segment is connected to resistance gene of antibiotics that is expressible in the Streptomyces tenebrarius such as erythromycin resistance gene ermE, and three gene segments are connected to shuttle vector pHZ132 by using Bg1II Enzyme cutting. The engineering bacteria directly producing tobramycin and the application thereof can simplify the production technology and reduce the production cost, thus facilitating the quality control of the products.

The invention discloses a lactobacillus food grade expression vector pMG36N which does not contain erythrocin resistance gene, introduces a natural food preservative streptococcus lactis peptide Nisinresistance gene nisI as a selection mark. The invention also discloses a preparation method of the lactobacillus food grade expression vector pMG36N. The lactobacillus food grade expression vector pMG36N does not take the resistance gene, i.e. erythrocin and the like, as a screening mark, enhances the safety of lactobacillus and can be used for food production.

The invention provides a rapid screening system for Lactococcus lactis with knocked-in exogenous genes. The screening system comprises temperature-sensitive plasmids and the Lactococcus lactis, wherein the temperature-sensitive plasmids contain his gene segments and temperature-sensitive replicon-erythromycin resistance gene (Ts-Emr) segments; chromosomes of the Lactococcus lactis contain lacZ gene expression segments. lacZ genes of the Lactococcus lactis cannot be expressed when the exogenous genes are knocked in successfully, so that white colonies are shown on a solid medium containing X-Gal, otherwise, blue colonies are shown, the change from the blue colonies to the white colonies can be directly observed on the solid medium, the screening workload can be greatly reduced, and screening time can be greatly shortened.

The invention relates to a method for constructing a lactobacillus expression plasmid with Nisin as a natural resistance selection marker, belonging to the technical field of biology. The method is characterized by using a Nisin element from a lactobacillus vector pNZ9530 instead of erythromycin resistance genes of a lactobacillus plasmid pMG36e as the selection marker and realizing construction of a Nisin food-grade expression/secretion vector through PCR (polymerase chain reaction) amplification, gene cloning, synthesis of multiple cloning sites, addition of lactobacillus acidophilus signal peptide and elimination of resistance genes. The method has the following beneficial effects: the antibiotic resistance marker vector is replaced by the food-grade selection marker and the constructed food-grade expression/secretion vector is a food-grade live vector, has high safety factors to human body and environment and can be widely applied to application research of vaccines, food and medicines; and the construction method can achieve long-term stable expression of the exogenous antigen genes and obtain the target antigen proteins stably expressed for a long term, is simple and is strong in operability.

The invention discloses a building method and application of a lactobacillus reuteri resistance-marker-free gene integration system. By means of the point mutation technology, a point mutation gene pheSM of a lactobacillus reuteri pheS gene is obtained, the point mutation gene pheSM and a erythromycin resistance gene are used for building an integrated framework LR-pheSM-em-RR, the integrated framework LR-pheSM-em-RR is electrically converted into L.renteri XNY competent cells, and pheSM genetic recombination lactobacillus L.renteri XNYM is obtained through erythromycin screening; then, the gene integration framework is constructed and inserted, then the gene integration framework is electrically converted into pheSM gene recombination lactobacillus reuteri competent cells, and the lactobacillus reuteri without resistance markers can be obtained through para-chlorophenylalanine acid resistance screening. According to the method, resistance genes are not introduced into host bacteria genomes, so that biological safety hidden hazards of the resistance genes and the polarity effect of the resistance genes on upstream genes and downstream genes are avoided. By means of the system, gene targeted integration can be carried out on the host bacteria for multiple times.

The invention discloses an overexpressed UGPase (UDP-glucose pyrophosphorylase) gene and a method for constructing recombinant lactobacillus acidophilus thereof. The method is characterized by comprising the specific steps as follows: (1) a UGPase gene LBA0625 is amplified with lactobacillus acidophilus genome DNA as a template; an expression vector pMG36e is subjected to single restriction digest with restriction enzyme Hind III, and after dephosphorylation and gel recovery are performed, a recombinant expression vector is constructed by inserting a PCR amplification product into the expression vector pMG36e; (2) an overexpression plasmid subjected to extraction and concentration is imported into lactobacillus acidophilus through electrotransformation, the lactobacillus acidophilus is resuscitated at 37 DEG C for 2 h, applied to an erythrocin resistant plate and cultured at 37 DEG C for 36 h for screening transformants; the transformants are subjected to PCR verification, and the recombinant lactobacillus acidophilus PLY127-1 of the overexpressed UGPase gene is obtained. The freeze-drying survival rate of the lactobacillus acidophilus can be increased substantially.

The invention relates to a primer for rapidly detecting the drug tolerance of pertussis bordelella erythrocin from a specimen and a detection method. The primer includes variable areas on both sides of a locus 2047 specific to a pertussis bordelella 23S rRNA (ribosomal Robonucleic Acid) gene. According to the primer, the technical problems of incapability of carrying out antibiotic susceptibility test, high time consumption of the antibiotic susceptibility test and the like due to incapability of successfully culturing the pertussis bordelella existing in the prior art are solved.

A useful novel compound that shows superior antibacterial activity also against erythromycin resistant bacteria, for example, resistant pneumococci, streptococci, mycoplasmas, and the like, against which sufficient antibacterial activity cannot be obtained with conventional macrolide antibiotics, or a pharmaceutically acceptable salt thereof, or a hydrate or a solvate thereof.

The invention discloses a streptococcus suis efficient transposon mutation system, namely a pSET4s-Tn plasmid, which comprises: (1) a streptococcus suis temperature-sensitive replication element Ts ori; (2) an escherichia coli replication element ColE1ori; (3) a Mariner transposase expression box; (4) a spectinomycin resistance expression cassette (SpcR); and (5) an erythromycin resistance expression cassette (ErmR) containing a transposase recognition sequence (IR) at each of the upstream and the downstream. By utilizing the transposon mutation system, efficient transposon mutation in streptococcus suis can be realized, more than 98% of streptococcus suis can be used as transposon mutants in a single experiment, the transposon is inserted into a TA base site in a streptococcus suis genome, and the transposon insertion site has no obvious preference.

The invention discloses an establishment method of a streptomyces diastatochromogenes expression system. The establishment method comprises the following steps of: screening a necessary or efficient ingredient of the streptomyces diastatochromogenes expression system by virtue of a green fluorescent protein gene gfp at first, and then constructing the expression system of a target gene, wherein the necessary or efficient ingredient is erythromycin resistance genome constructive promoter permE*; the target gene promotes production of toyocamycin; and the target gene is a haemoglobin gene vgb. The construction processes are as follows: 1) constructing a carrier pIB139-gfp; and 2) integrating the expression carrier into a streptomyces diastatochromogenes chromosome by virtue of a conjugational transfer method, so as to obtain a recombinant bacterium. The invention provides an efficient screening method and application of the streptomyces diastatochromogenes expression system. Compared with the original strain, the recombinant bacterium has the advantages that the toyocamycin yield of the recombinant bacterium is increased by at least 21.2%, and the concentration of the recombinant bacterium is increased by 11.6%.

The invention discloses an overexpression UTP-glucose-1-phosphate-uridine transferase gene, and a construction method and an application of a recombinant engineering bacterium of the overexpression UTP-glucose-1-phosphate-uridine transferase gene. The gene is a Lactobacillus acidophilus ATCC 4356 gene from a gene for encoding the UTP-glucose-1-phosphate-uridine transferase, and the nucleotide sequence of the overexpression UTP-glucose-1-phosphate-uridine transferase gene is represented by SEQ ID No:1 in a sequence table. The construction method comprises the following steps: the UTP-glucose-1-phosphate-uridine transferase gene segment of Lactobacillus acidophilus ATCC4356 is cloned and is connected to a pMG36e expression vector, the obtained substance is introduced to Staphylococcus carnosus or Lactococcus lactis by using an electric conversion method, and erythromycin resistance screening and identification are performed to obtain the recombinant engineering strain with the target gene, that is the engineering bacterium of the overexpressed UTP-glucose-1-phosphate-uridine transferase gene. The construction method has the advantages of significantly improving bacterial growth, enzyme activity and the freeze-drying survival rate.

The invention provides a composition for detecting methicillin-resistant and/or erythromycin-resistant staphylococcus aureus. The composition comprises a primer pair SEQ ID NO.1/2, a primer pair SEQ ID NO.3/4, a primer pair SEQ ID NO.5/6 and a primer pair SEQ ID NO.7/8. When the staphylococcus aureus is subjected to bacterial genus identification by using the composition disclosed by the invention as well as a corresponding detection method, MRSA and erythromycin drug-resistant genes can be simultaneously detected. The composition has the advantages of rapidness, high throughput and the like, and the requirement for rapidly and accurately detecting microbes in food is met. By utilizing an mPCR-DHPLC/electrophoresis method established by the invention, the staphylococcus aureus, MRSA and erythromycin-resistant staphylococcus aureus in samples can be simultaneously identified through one time of detection. Moreover, by using the composition, the detection consumes less time, is easy and rapid to operate and suitable for rapid detection requirement and can save lots of labor force and financial resources.

A novel 10a-azalide compound crosslinked at the 10a- and 12-positions, which is represented by the following formula, and is effective on even Hemophilus influenzae, or erythromycin resistant bacteria (e.g., resistant pneumococci and streptococci).

The present disclosure relates to method for detecting P. acnes as well as a method for detecting mutation in genomic sequence of 23S rRNA sequence of P. acnes, particularly mutation A2058G. The method comprises amplifying a region of 23S rRNA specific for P. acnes using primers of SEQ ID Nos. 1 and 2 followed by detecting the mutation through selective action of an endonuclease- at a mismatch at the site of said mutation or post-hybridization with specific P. acnes 23S regions followed by mismatch specific endonuclease action. The presence of A2058G mutation confers antibiotic resistance, particularly clindamycin and erythromycin resistance, and thus the present disclosure also relates to methods of treating acne caused by clindamycin resistant P. acnes by using fluoroquinolone based antibiotics.