摘要:
DNA sequences are described which on the codogenic strand code plant debranching enzymes, whose transcripts formed in transgenic plants code new proteins with the enzymatic activity of debranching enzymes which in transgenic plants reduce the degree of branching of amylopectin starch and DNA sequences which on the codogenic strand code plant debranching enzymes, whose transcripts formed in transgenic plants prevent the synthesis of proteins with the enzymatic activity of debranching enzymes, which in the transgenic plants increases the degree of branching of amylopectin starch, as well as plasmids on which these DNA sequences are localized, which can be introduced into plant cells and plants. Also described is a process for the production of plants changed by genetic engineering whose amylopectin starch is modified, and the modified starch obtainable from these plants.
摘要:
SU1, a starch debranching enzyme active in maize endosperm (Zea mays), and the cDNA and gene sequences encoding SU1 are disclosed. The amino acid sequence is significantly similar to that of bacterial isoamylases, enzymes that hydrolyze .alpha.-(1.fwdarw.6) glycosidic bonds. Amino acid sequence similarity establishes SU1 as a member of the .alpha.-amylase superfamily of starch hydrolytic enzymes. Also disclosed are antibodies reactive with the SU1 protein, methods of producing antibodies to the SU1 protein, methods of producing fusion proteins including SU1 and methods of producing transgenic plants with a modified su1 gene. The expressed SU1 protein can serve as a replacement for the bacterial and fungal enzymes currently used in the starch processing industry.
摘要:
The present invention relates to an amylase isolated from Staphalothermus marinus, DSM 3639, having a temperature optima of 95.degree.-105.degree. C., determined at pH 5.5 and a pH optima of 4.5 to 5.5, determined at 95.degree. C. The amylase can be employed in the production of sweeteners and ethanol.
摘要:
The present invention relates to a method for recovery and purification of isoamylase by raw starch adsorption method. Various raw starches are used to recover the isoamylase produced by a bacterium such as Pseudomonas amyloderamosa. The method comprises using raw starch to adsorb isoamylase under conditions suitable for such adsorption and isolating the adsorbed enzyme. The isoamylase adsorption rate varied with the species of raw starch. Additionally, raw starch can be recycled.
摘要:
A crystallizable, purified chondroitinase ABC having a molecular weight of about 100,000 dalton by the measurement of the SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and the measurement by the gel permeation chromatography method, having alanine as the N-terminal amino acid and proline as the C-terminal amino acid is disclosed. A process for the purification of the crystallizable purified chondroitinase ABC comprising removing nucleic acid from an surfactant solution extract obtained from cells of chondroitinase ABC-producing microorganisms and chromatographically treating by concentration gradient elution using a weak cation exchange resin or a strong cation exchange resin is disclosed. A composition comprising a chondroitinase and serum albumin, gelatin, or a nonionic surfactant is disclosed. The enzyme is isolated from Proteus vulgaris ATCC 6896.
摘要:
A method of producing plant products containing modified starch content, including higher ratios of amylose to amylopectin, increase in intermediate material, or amylopectin having fewer branches or altered branching pattern. Also provided are DNA constructs and transformed plant cells useful in that method. The preferred method uses isoamylase from a Flavobacterium sp., more preferably in combination with a gene encoding ADPglucose pyrophosphorylase. Also disclosed are the gene from Flavobacterium sp. and transformed bacterial and plant cells containing a derivative thereof.
摘要:
The structural gene encoding isoamylase from Pseudomonas SMP 1 is obtained. Also described are vectors comprising the isoamylase gene and host microorganisms transformed by these vectors. The transformed host microorganisms are capable of expressing and/or secreting mature isoamylase having biological activity.
摘要:
An isolated alkaline pullulanase Y having .alpha.-amylase activity; a microorganism producing the alkaline pullulanase Y; and a process for producing the alkaline pullulanase Y are disclosed. The alkaline pullulanase Y having .alpha.-amylase activity has its optimum pH at higher alkaline range than conventional alkaline pullulanases and exhibits excellent stability in a wide pH range. Further, the alkaline pullulanase Y has strong resistance to almost all detergent components such as surfactants, chelating agents, proteases for detergents, and the like. Thus the alkaline pullulanase Y can advantageously be used as a detergent component.
摘要:
A novel alkaline pullulanase; a microorganism producing the alkaline pullulanase; and a process for producing the alkaline pullulanase are disclosed. The alkaline pullulanase of the present invention has a higher optimum pH range (pH 9.5-11) than conventional alkaline pullulanases and shows excellent stability in a wider pH range. It has also an optimum temperature of higher than 50.degree. C. and is thermally stable up to 40.degree. C. The alkaline pullulanase has also strong reistance to almost all detergent components such as surfactants, chelating agents, proteases for detergents, and the like. The alkaline pullulanase can advantageously be used as a detergent component. Also, it can be utilized for producing many kinds of oligosaccharides and also together with .alpha.-amylase for producing various monosaccharides.