370 results about "Substrate specificity" patented technology

An acyltransferase is provided, suitable for use in the manufacture of microbial oils enriched in omega fatty acids in oleaginous organisms. Specifically, the gene encoding diacylglycerol acyltransferase (DGAT2) has been isolated from Mortierella alpina. This gene encodes an enzyme that participates in the terminal step in oil biosynthesis in fungi and yeast and is expected to play a key role in altering the quantity of long-chain polyunsaturated fatty acids produced in oils of oleaginous organisms. Most desirably, the substrate specificity of the instant DGAT2 will be particularly useful to enable accumulation of long-chain PUFAs having chain lengths equal to or greater than C20 in oleaginous yeast, such as Yarrowia lipolytica.

Glycerol-3-phosphate o-acyltransferase (GPAT) participates in the first step of oil biosynthesis and is expected to play a key role in altering the quantity of long-chain polyunsaturated fatty acids (PUFAs) produced in oils of oleaginous organisms. The present application provides a nucleic acid fragment isolated from Mortierella alpina encoding a GPAT that is suitable for use in the manufacture of oils enriched in omega fatty acids in oleaginous organisms. Most desirably, the substrate specificity of the instant GPAT will be particularly useful to enable accumulation of long-chain PUFAs having chain lengths equal to or greater than C20 in oleaginous yeast, such as Yarrowia lipolytica.

Treatment of warm-blooded animals having a tumor or non-malignant hypervascularation, by administering a sufficient amount of a cytotoxic agent formulated into a phosphate prodrug form having substrate specificity for microvessel phosphatases, so that microvessels are destroyed preferentially over other normal tissues, because the less cytotoxic prodrug form is converted to the highly cytotoxic dephosphorylated form.

The present invention relates to improved variants of soluble pyrroloquinoline quinone (PQQ)-dependent glucose dehydrogenases (s-GDH), to genes encoding mutated s-GDH, to mutant proteins of s-GDH with improved substrate specificity for glucose, and to different applications of these s-GDH variants, particularly for determining concentrations of sugar, especially of glucose in a sample.

Complex multidimensional datasets generated by digital imaging spectroscopy can be organized and analyzed by applying software and computer-based methods comprising sorting algorithms. Combinations of these algorithms to images and graphical data, allow pixels or features to be rapidly and efficiently classified into meaningful groups according to defined criteria. Multiple rounds of pixel or feature selection may be performed based on independent sorting criteria. In one embodiment sorting by spectral criteria (e.g., intensity at a given wavelength) is combined with sorting by temporal criteria (e.g., absorbance at a given time) to identify microcolonies of recombinant organisms harboring mutated genes encoding enzymes having desirable kinetic attributes and substrate specificity. Restriction of the set of pixels analyzed in a subsequent sort based on criteria applied in an earlier sort (“sort and lock” analyses) minimize computational and storage resources. User-defined criteria can also be incorporated into the sorting process by means of a graphical user interface that comprises a visualization tools including a contour plot, a sorting bar and a grouping bar, an image window, and a plot window that allow run-time interactive identification of pixels or features meeting one or more criteria, and display of their associated spectral or kinetic data. These methods are useful for extracting information from imaging data in applications ranging from biology and medicine to remote sensing.

There are provided a highly safe epimerase usable in food industry, and a method for producing a ketose. The epimerase is a ketose 3-epimerase obtainable from a microorganism of the genus Arthrobacter, and having the amino acid sequence represented by SEQ ID NO: 1 of the Sequence Listing, and (1) substrate specificity whereby a D- or L-ketose is epimerized at position 3 to produce a corresponding D- or L-ketose, and (2) the highest substrate specificity for D-fructose and D-psicose among D- and L-ketoses. The ketose 3-epimerase is also represented by SEQ ID NO: 3 or SEQ ID NO: 4 of the Sequence Listing, and epimerizes a D- or L-ketose at position 3 to produce a corresponding D- or L-ketose.

A novel glucose dehydrogenase, which is an enzyme that has high substrate specificity, can be produced at a low cost, is not affected by oxygen dissolved in a measurement sample and, in particular, has superior thermal stability is obtained by culturing a microorganism belonging to the genus Burkhorderia and having glucose dehydrogenase producing ability in a medium and collecting glucose dehydrogenase from the medium and / or cells of the microorganism.

The present invention provides a protein having low-substrate-specific amino acid racemase activity; DNA encoding the protein; a recombinant DNA comprising the DNA; a transformant carrying the recombinant DNA; a process for producing the protein by using the transformant; and a process for producing a racemic amino acid which comprises allowing a culture of the transformant or a treated matter thereof as an enzyme source and an amino acid to be present in an aqueous medium to racemize the amino acid in the aqueous medium, and recovering the racemic amino acid from the aqueous medium.

The object of the present invention is to provide a novel dehydrogenase having a property which is different from that of known dehydrogenases. The present invention provides a dehydrogenase having the following physicochemical properties: (1) effect: to produce N-alkyl-L-alanine from pyruvic acid and alkylamine or dialkylamine using NADPH and / or NADH as coenzyme; (2) substrate specificity: to show activity to alkylamine or dialkylamine but not to ammonium; (3) optimal pH when using phenylpyruvic acid and methylamine as substrates is around 10; and (4) when treated at 30° C. for 30 minutes, the enzyme is stable at around pH 5 to 10.5.

The invention discloses a keratinase mutant with improved thermal stability and a preparation method thereof, and belongs to the field of enzyme engineering. Thermal stability and substrate specificity of the keratinase are improved by interchanging N ends or C ends of two different keratinases with higher homology from the same bacterial strain. The keratinase and the mutant thereof can effectively hydrolyze water-insoluble keratinase substrates such as feathers, wools, and the like, and can be used for leather spinning industry and feed industry.

A flavin-binding glucose dehydrogenase (FAD-GDH), which in addition to having high substrate specificity and adequate desirable heat stability, is suitable for efficient production, preferably using E. coli, yeast or molds and the like as host cells. The FAD-GDH has amino acid substitutions at positions equivalent to one or more locations selected from the group consisting of position 213, position 368 and position 526 in the amino acid sequence described in SEQ ID NO: 8. The FAD-GDH is acquired from a culture by inserting a gene encoding the FAD-GDH into host cells such as E. coli. A preferable example of the FAD-GDH is FAD-GDH, in which a signal peptide region present in an N-terminal region has been deleted from the amino acid sequence of Mucor-derived FAD-GDH, and which has the aforementioned amino acid substitutions. The FAD-GDH can be preferably used in clinical diagnosis.

The present invention provides methods and compositions useful in the screening for agents that modulate activity of a deubiquitinating enzyme. In one embodiment, the invention relates to methods for measuring a deubiquitination activity comprising combining a deubiquitinating enzyme (DUB) with a substrate comprising a ubiquitin moiety and a fluorescently labeled compound under conditions allowing for deubiquitinating activity and measuring an altered fluorescence polarization and / or fluorescence lifetime of the released fluorescently labeled compound The invention also relates to a substrate library comprising peptides of the formula (Z)a(X)mK(X)n(Z)b useful e.g. for the determination of the substrate specificity of a deubiquitinating enzyme.

Provided are compounds comprising a self-immolative group, and the compounds comprising a self-immolative group according to the present invention may include a protein (for example, an oligopeptide, a polypeptide, an antibody, or the like) having substrate-specificity for a target and an active agent (for example, a drug, a toxin, a ligand, a detection probe, or the like) having a specific function or activity.

The invention discloses a method for converting astragalosides to prepare cycloastragenol by two-step enzymolysis; the method comprises the specific steps of using astragalosides as a substrate, using two different hydrolases to hydrolyze and break beta-xyloside bond at site C3 of the astragalosides and beta-glucoside bond at the site C6 respectively to obtain aglycone cycloastragenol of the astragalosides, extracting, performing silica-gel column chromatography, recrystallizing with ethanol, and purifying to obtain the finished cycloastragenol up to 95% and higher in purity. The problem that damage of three-membered ring structure of astragalosides during the preparation of cycloastragenol by a chemical process causes massive byproducts is solved, the defects of traditional cycloastragenol preparation methods, such as low substrate conversion rate, step complexity and environmental pollution, are overcome. The method has the advantages that substrate specificity is high, the substrate astragalosides is completely converted, the steps are simple, the conditions are mild, the cost is low, and the method is a mild biological preparation method, has no environmental pollution and is suitable for industrial production.