525 results about "E coli bacteria" patented technology

The inventive method allows peptides or polypeptides to be exposed on the surface of gram-negative host bacteria using specific intimin-based anchor modules. Intimins with shortened carboxy terminals have been found to be particularly suitable anchor modules for passenger domains in the exterior E. coli cell membrane. According to the method, host bacteria are transformed using vectors, on which are located a fused nucleic acid sequence consisting of a sequence segment which codes for an intimin with a shortened carboxy terminal and a nucleic acid sequence segment which codes for the passenger peptide that is to be exposed. The invention permits a particularly large number of passenger domains to be exposed on the cell surface of the bacteria, without adversely affecting the viability of the bacteria.

The invention provides isolated and recombinant phytase enzymes. In one aspect, the phytases are produced by modification of the wild type appA of E. coli. The enzyme can be produced from recombinant host cells. The phytases of the invention can be used to aid in the digestion of phytate where desired. In particular, the phytases of the invention can be used in foodstuffs to improve the feeding value of phytate rich ingredients. The phytases of the invention can be thermotolerant and / or thermostable. Also provided are methods for obtaining a variant polynucleotide encoding a phytase and for obtaining a phytase with thermostability or thermotolerant at high or low temperatures.

The invention relates to a substantially pure thermostable DNA polymerase from Thermotoga (Tne and Tma) and mutants thereof. The Tne DNA polymerase has a molecular weight of about 100 kilodaltons and is more thermostable than Taq DNA polymerase. The mutant DNA polymerase has at least one mutation selected from the group consisting of (1) a first mutation that substantially reduces or eliminates 3'->5' exonuclease activity of said DNA polymerase; (2) a second mutation that substantially reduces or eliminates 5'->3' exonuclease activity of said DNA polymerase; (3) a third mutation in the O helix of said DNA polymerase resulting in said DNA polymerase becoming non-discriminating against dideoxynucleotides. The present invention also relates to the cloning and expression of the wild type or mutant DNA polymerases in E. coli, to DNA molecules containing the cloned gene, and to host cells which express said genes. The DNA polymerases of the invention may be used in well-known DNA sequencing and amplification reactions.

A flavin-bound glucose dehydrogenase (FAD-GDH) with high substrate specificity for D-glucose. A gene encoding a mutant FAD-GDH with its N-terminal region, containing an amino acid sequence corresponding to MKITAAIITVATAFASFASA that exists in the N-terminal region, deleted from the amino acid sequence of a wild-type FAD-GDH derived from Mucor is introduced into E. coli to obtain an E. coli transformant. Subsequently, this E. coli transformant is cultured to obtain an FAD-GDH with a specific N-terminal region deleted. The transformant allows the production of a large amount of GDH in a short time as compared with the original microorganism. An FAD-GDH that is less susceptible to the effects of dissolved oxygen and allows accurate measurement of glucose even in the presence of sugar compounds other than glucose in a sample.

An E. coli host strain was engineered wherein genes adhE, IdhA, frdB, and pfIB were disrupted and novel butanol dehydrogenase gene, sadB, from Achromobacter xylosoxidans, was added to produce the isobutanol production host.

The invention provides compositions and methods for engineering E. coli or other host production bacterial strains to produce fucosylated oligosaccharides, and the use thereof in the prevention or treatment of infection.

The invention provides isolated and recombinant phytase enzymes. In one aspect, the phytases are produced by modification of the wild type appA of E. coli. The enzyme can be produced from recombinant host cells. The phytases of the invention can be used to aid in the digestion of phytate where desired. In particular, the phytases of the invention can be used in foodstuffs to improve the feeding value of phytate rich ingredients. The phytases of the invention can be thermotolerant and / or thermostable. Also provided are methods for obtaining a variant polynucleotide encoding a phytase and for obtaining a phytase with thermostability or thermotolerant at high or low temperatures.

The invention provides a bacterium attenuated by a non-reverting mutation in each of the aroC gene, the ompF gene and the ompC gene. The bacterium is useful as a vaccine. The bacterium may, for example, be an attenuated strain of E. coli useful in vaccination against diarrhoea.

The invention relates to a method for biosynthesis preparation of human glucagon-like peptide-1 (GLP-1) and an analogue thereof. With adopting of a gene engineering technology, a recombinant escherichia coli expressed GLP-1 fusion protein is constructed, and a protein enzyme digestion site is designed in the fusion protein; a fusion gene has a gene sequence with a form of A-B-C structure, wherein A is a chaperonin gene, B is a nucleotide sequence encoding a connection peptide containing the enzyme digestion site, and C is a gene encoding the GLP-1 or the analogue thereof. After recombinant engineering bacteria is subjected to induced expression, the fusion protein is purified and subjected to enzyme digestion, and then the GLP-1 and the analogue thereof are obtained and are detected to have biological activity. The preparation method of the GLP-1 and the analogue thereof provided by the invention is simple and quick, the production conditions are mild, the product is convenient to separate and extract, the process is simple, and the industrialization prospect is good.

Recombinant bacterial triple-helical collagen-like proteins comprising two or more repetitive sequences of Gly-Xaa-Yaa yielding high-stability polymeric constructs without the need for post-translational modifications and which may incorporate one or more functional domains of biological or structural importance. The polymers are capable of high-yield production for a variety of applications

The invention discloses an E. coli BL21(pETDuet-ydjLnox) containing a 2R,3R-butanediol dehydrogenase gene ydjL and an NADH oxidase gene nox, wherein the strain is preserved in the 'China Center for Type Culture Collection' on December 23 in 2008, and the preservation number is CCTCC NO: M 208259. The invention also discloses application of a gene recombination bacterium in producing chiral S-AC by catalyzing meso-BD, producing chiral R-AC by catalyzing 2R,3R-BD and producing chiral pure 2S,3S-BD by splitting a 2,3-BD mixture. The concentration of a chiral AC prepared from the recombinant E. coli can reach over 6 grams per liter (the ee value is more than or equal to 96 percent); and the ee value of the chiral pure 2S,3S-BD is more than or equal to 98 percent, and the regeneration of a cofactor is achieved, thus the gene recombination bacterium has great industrial application prospect.

The present invention relates to a method for the detection of pathogenic E. coli in a sample comprising PCR amplification of DNA isolated from said sample using oligonucleotide primers specific for pathogenic E. coli.

The invention relates to orthogonal pairs of tRNAs and aminoacyl-tRNA synthetases that can incorporate the unnatural amino acid sulfotyrosine into proteins produced in eubacterial host cells such as E. coli. The invention provides, for example but not limited to, novel orthogonal aminoacyl-tRNA synthetases, polynucleotides encoding the novel synthetase molecules, methods for identifying and making the novel synthetases, methods for producing proteins containing the unnatural amino acid sulfotyrosine and translation systems.

The invention relates to a PE (polyethylene) preservative film containing glass-carrier silver-ion antibacterial agent. An ordinary PE (polyethylene) preservative film contains 0.05 percent to 1 percent of glass-carrier silver-ion antibacterial agent, or further contains one or more of 0.1 percent to 1.5 percent of tackifier, 1 percent to 5 percent of antifogging agent and 0.05 percent to 0.4 percent of edible oil, and the PE in the PE (polyethylene) preservative film is low-density polyethylene or linear low-density polyethylene, or the mixture of low-density polyethylene and linear low-density polyethylene according to a certain proportion. In the preparation technique, the PE polyethylene and the glass-carrier silver-ion antibacterial agent are mixed and pelleted by a single-screw or double-screw extruder, so that antibacterial masterbatches are produced. The extruder then produces the antibacterial preservative film according to the formula by way of casting or film blowing. The product has a high antibacterial property and is durable, and the color cannot be easily changed. In particular, the preservative film has excellent inhibiting and sterilizing effects on bacteria such as colibacillus and staphylococcus aureus.

The antimicrobial agent includes at least one two-dimensional metal carbide layer. The two-dimensional metal carbide has the formula Tin+1CnTx, where T represents a terminal functional group and x represents the number of terminal functional groups. The two-dimensional metal carbide is preferably Ti3C2Tx. The terminating group may be oxygen, hydroxide (OH), fluorine or combinations thereof. The antimicrobial agent may be used as a two-dimensional metal carbide antimicrobial membrane (10) or filter for removal of harmful bacteria, such as E. coli and B. subtilis. A stack of two-dimensional metal carbide layers (14) may be supported on a polymer filter substrate (12), such as a polyvinylidene fluoride (PVDF) supporting substrate.

The present invention provides several methods for biological production of para-hydroxycinnamic acid (PHCA). The invention is also directed to the discovery of new fungi and bacteria that possess the ability to convert cinnamate to PHCA. The invention relates to developing of a new biocatalyst for conversion of glucose to PHCA by incorporation of the wild type PAL from the yeast Rhodotorula glutinis into E. coli underlining the ability of the wildtype PAL to convert tyrosine to PHCA. The invention is also directed to developing a new biocatalyst for conversion of glucose to PHCA by incorporation of the wildtype PAL from the yeast Rhodotorula glutinis plus the plant cytochrome P-450 and the cytochrome P-450 reductase into E. coli. In yet another embodiment, the present invention provides for the developing of a new biocatalyst through mutagenesis of the wild type yeast PAL which possesses enhanced tyrosine ammonia-lyase (TAL) activity.

The present invention generally provides compositions comprising a polysaccharide derivative, and methods of their preparation and use for the prevention or treatment of diseases caused by Neisseria meningitidis bacteria, particularly group B (NmB) strains, and by E. coli K1. The invention provides a de-N-acetylated PS derivative in which one or more residues of the PS has been modified by de-N-acetylation. The invention also includes derivatives in which one or more of the N-acetyl groups of PS containing de-N-acetylated PS are replaced with other N-acyl groups, usually a lower acyl group of C2-C3. Further, the invention includes de-N-acetylated PS derivatives containing long chain hydrocarbons, as well as conjugates in which the de-N-acetylated PS derivative is linked to a carrier, e.g., a carrier protein.

Recombinant host cells are obtained that comprise (A) a heterologous, polypeptide-encoding polynucleotide segment, stably integrated into a chromosome, which is under transcriptional control of an endogenous promoter and (B) a mutation that effects increased expression of the heterologous segment, resulting in enhanced production by the host cells of each polypeptide encoded by that segment, relative to production of each polypeptide by the host cells in the absence of the mutation. The increased expression thus achieved is retained in the absence of conditions that select for cells displaying such increased expression. When the integrated segment comprises, for example, ethanol-production genes from an efficient ethanol producer like Zymomonas mobilis, recombinant Escherichia coli and other enteric bacterial cells within the present invention are capable of converting a wide range of biomass-derived sugars efficiently to ethanol.

The present invention relates to non-activated Wnt inhibition polypeptides (WIPs) containing: (a) a protein transduction domain (PTD) which enables said WIPs to permeate a cell membrane without the aid of a cell membrane receptor; and (b) a Wnt antagonist domain which is inactive by itself, but is activated in mammalian cells and then secreted out of the cells to function to inhibit Wnt signal transduction. Also, the invention relates to a method for preparing said non-activated WIPs, and a pharmaceutical composition containing said WIPs as active ingredients. Said non-activated WIPs can be produced in large quantities through the culture of bacteria such as E coli., and are biochemically inactive before being administered into the human body, and thus the production cost thereof is only one several tenths of that of previously known active proteins (sFRPs, DKKs, etc.) having uses similar thereto, and the isolation / purification and handling / administration processes thereof are significantly simple and convenient. When said non-activated WIPs are administered in vivo, they will have the effects of inhibiting the invasive growth and metastasis of cancer cells and treating immune diseases, such as rheumatoid arthritis by pharmacological mechanisms different from those of the previously known sFRPs or DKKs.

The present invention relates to production of ubiquinone-10 in E. coli by isolating and sequencing a structural gene dds1 of decaprenyl diphosphate synthase derived from photosynthetic bacteria such as Rhodobacter capsulatus., and expressing it in E. coli.

The invention provides a 3-sterone-9Alpha-hydroxylation enzyme gene and a 3-sterone-9Alpha-hydroxylation enzyme reductase gene. By constructing various expression vectors and converting relevant strains, the invention obtains various high-expression strains such as escherichia coli, streptomyces and mycobacterium; furthermore, the mycobacterium of the 3-sterone-9Alpha-hydroxylation enzyme activity can be prepared; the prepared high-expression strains or other crude enzyme liquid can be used for catalyzing and producing the 3-sterone-9Alpha-hydroxylation steroid compounds; the mycobacterium of the 3-sterone-9Alpha-hydroxylation enzyme activity can be used for degrading sterol to prepare androst-4-alkene-3, 17-diketone or androst-1, 4-diene-3, 17-diketone; the engineering stains can greatly improve the production efficiency and product quality of the steroid drugs, are beneficial for reducing the energy consumption of steroid drugs during the production process, improving the utilization ratio of the prodrugs and simplifying the production steps, reduce the production cost, have moderate reaction conditions and friendly environment, are suitable for wide generalization and application and have higher economic benefits and social benefits.

The invention provides strains of bacteria, especially enterotoxigenic E. coli, attenuated by mutations in the genes encoding enterotoxins (LT, ST, EAST1) and optionally further attenuated by deletion of additional chromosomal genes. In addition the invention provides strains of attenuated bacteria expressing immunogenic but non-toxic variants of one or more of these enterotoxins. These bacteria are useful as a vaccine against diarrhoeal disease.

An antimicrobial, anti-bacterial processing aid, food additive and food ingredient is provided to inhibit cellular growth of known pathogenic, indicator and spoilage organisms, such as salmonella, stahphylococcus, listeria, e coli, and the like. The antimicrobial agent of the present invention is useful as a treatment for animal feed, a treatment for pre-harvest and post-harvest processing of foodstuffs, a treatment for cooked food subject to airborne contaminants and many other conditions in need of disinfectants and sanitizers. One of the primary benefits of the antimicrobial agent is that it inhibits the growth of bacteria that have become antibiotic resistant.