Construction of new variants of dextransucrase DSR-S by genetic engineering
    9.
    发明授权
    Construction of new variants of dextransucrase DSR-S by genetic engineering 有权
    通过基因工程构建葡聚糖蔗糖酯酶DSR-S的新变体

    公开(公告)号:US07897373B2

    公开(公告)日:2011-03-01

    申请号:US12223744

    申请日:2007-02-08

    IPC分类号: C12N9/24 C07H21/04

    摘要: The present invention relates to a recombinant process for the production of truncated or mutated dextransucrases while conserving the enzymatic activity or their specificity in the synthesis of the α-1,6 bonds. The present invention relates to nucleic acid sequences of truncated or mutated dextransucrases, vectors containing the nucleic acid sequences and host cells transformed by sequences encoding truncated or mutated dextransucrases. In another aspect, the invention concerns a method for producing, in a recombinant manner, truncated or mutated dextransucrases which conserve their enzymatic activity or which conserve their specificity in the synthesis of α-1,6 bonds and can produce, from saccharose, dextrans with high molar mass and modified rheological properties compared with the properties of dextran obtained with the native enzyme and isomalto-oligosaccharides with a controlled molar mass and dextrans. The dextrans and isomalto-oligosaccharides of the invention can be used namely as texturing agents or as prebiotics.

    摘要翻译: 本发明涉及一种在保护酶活性或其合成α-1,6键的特异性的同时生产截短或突变的葡聚糖蔗糖酶的重组方法。 本发明涉及截短或突变的葡聚糖蔗糖酶的核酸序列,含有核酸序列的载体和由编码截短或突变的葡聚糖蔗糖酶的序列转化的宿主细胞。 另一方面,本发明涉及一种以重组方式生产截短或突变的葡聚糖蔗糖酯的方法,其保留其酶活性或在合成α-1,6键时保护其特异性,并可从蔗糖,葡萄糖, 与用天然酶和具有受控摩尔质量的异麦芽低聚糖和葡聚糖获得的葡聚糖的性质相比,具有高的摩尔质量和改进的流变学性质。 本发明的葡聚糖和异麦芽低聚糖可以用作变形剂或益生元。