Properties of recombinant 4-α-glucanotransferase from Bifidobacterium longum subsp. longum JCM 1217 and its application
Properties of recombinant 4-α-glucanotransferase from Bifidobacterium longum subsp. longum JCM 1217 and its application
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DOI：
10.1007/s10068-019-00707-4
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发表时间：
2019-12
影响因子：
2.9
通讯作者：
D. Jeong;Hyun-Mo Jeong;Yu-Jeong Shin;Seung-Hye Woo;J. Shim
中科院分区：
文献类型：
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作者：
D. Jeong;Hyun-Mo Jeong;Yu-Jeong Shin;Seung-Hye Woo;J. Shim
测定双歧杆菌4-α-葡聚糖基转移酶的理化性质，从长双歧杆菌长亚种JCM 1217中克隆了编码4-α-葡聚糖转移酶的基因bllj_0114，并在大肠杆菌中表达。氨基酸序列分析表明，重组蛋白BL-α GTase属于糖苷水解酶（GH）家族77。BL-α GT酶经镍-次氮基三乙酸亲和层析纯化，并用不同底物进行了表征。该酶具有催化水解活性，将葡萄糖基单元从寡糖转移到受体分子，并且在40 ° C和pH 6.0下具有最高活性。在5 mM金属离子，特别是Cu 2+、Zn 2+和Fe 2+存在下，BL-α GT酶活性降低。为了确定BL-α GTase是否可用于产生热可逆凝胶，用BL-α GTase处理马铃薯淀粉不同的反应时间。BL-α GTase处理的淀粉具有溶胶-凝胶可逆性，并在59.6 - 75.7 ° C下熔化。
To determine the physiochemical properties of the 4-α-glucanotransferase fromBifidobacteriumsp., thebllj_0114 gene encoding 4-α-glucanotransferase was cloned fromBifidobacterium longumsubsp.longumJCM 1217 and expressed inEscherichia coli. The amino acid sequence alignment indicated that the recombinant protein, named BL-αGTase, belongs to the glycoside hydrolase (GH) family 77. BL-αGTase was purified using nickel-nitrilotriacetic acid affinity chromatography and characterized using various substrates. The enzyme catalyzed the disproportionation activity, which transfers a glucosyl unit from oligosaccharides to acceptor molecules, and had the highest activity at 40 °C and pH 6.0. In the presence of 5 mM metal ions, in particular Cu2+, Zn2+, and Fe2+, BL-αGTase activity was reduced. To determine whether BL-αGTase can be used to generate thermoreversible gels, potato starch was treated with BL-αGTase for various reaction times. The BL-αGTase-treated starches showed sol–gel reversibility and melted at 59.6–75.7 °C.