Novel Dextransucrase Gtf-DSM, Highly Similar in Sequence to Reuteransucrase GtfO, Displays Unique Product Specificity
Novel Dextransucrase Gtf-DSM, Highly Similar in Sequence to Reuteransucrase GtfO, Displays Unique Product Specificity
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新型右旋蔗糖酶 GTf-DSM，与 Reuteransucrase GtfO 序列高度相似，显示出独特的产品特异性
DOI：
10.1021/acs.jafc.9b04252
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发表时间：
2019-11-20
影响因子：
6.1
通讯作者：
Mu, Wanmeng
中科院分区：
文献类型：
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作者：
Chen, Ziwei;Tian, Yuqing;Mu, Wanmeng
已知乳酸菌产生胞外多糖，例如α-葡聚糖、莱万和菊粉，由于它们的益生元性质，它们在食品系统中的应用是有希望的。在这项工作中，重组表达了一种新的葡聚糖蔗糖酶（GS）Gtf-DSM，并将其生化表征为能够产生具有四种类型键的葡聚糖多糖的葡聚糖蔗糖酶，包括69%（α 1 -> 6）、24%（α 1 -> 3）、6%（α 1 -> 4）和1%（α 1 -> 2）。有趣的是，右旋糖酐蔗糖酶Gtf-DSM与产生具有21%（α 1 -> 6）和79%（α 1 -> 4）键的罗伊聚糖的罗伊聚糖蔗糖酶GtfO具有99.3%的序列同一性。因此，葡聚糖蔗糖酶Gtf-DSM是一个独特的目标，了解GS的连接特异性和定点突变的调查使用Gtf-DSM和GtfO作为模板正在进行中。
Lactic acid bacteria are known to produce extracellular polysaccharides such as a-glucan, levan, and inulin, which are promising for applications in food systems because of their prebiotic properties. In this work, a novel glucansucrase (GS) Gtf-DSM from Lactobacillus ingluviei DSM 14792 was recombinantly expressed and biochemically characterized as a dextransucrase capable of producing a dextran polysaccharide with four types of linkages, including 69% (alpha 1 -> 6), 24% (alpha 1 -> 3), 6% (alpha 1 -> 4), and 1% (alpha 1 -> 2). Intriguingly, the dextransucrase Gtf-DSM had a sequence identity of 99.3% with the reuteransucrase GtfO producing a reuteran with 21% (alpha 1 -> 6) and 79% (alpha 1 -> 4) linkages. Thus, the dextransucrase Gtf-DSM is a unique target for understanding the linkage specificity of GSs and the investigation of site-directed mutagenesis using Gtf-DSM and GtfO as templates is underway.