Cloning and sequencing of agaA, a unique agarase 0107 gene from a marine bacterium, Vibrio sp. strain JT0107
Cloning and sequencing of agaA, a unique agarase 0107 gene from a marine bacterium, Vibrio sp. strain JT0107
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DOI：
10.1128/aem.59.11.3750-3756.1993
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发表时间：
1993-11
影响因子：
4.4
通讯作者：
Yasushi Sugano;T. Matsumoto;Hisashi Kodama;M. Noma
中科院分区：
文献类型：
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作者：
Yasushi Sugano;T. Matsumoto;Hisashi Kodama;M. Noma
从弧菌JT 0107菌株基因组DNA中克隆了琼胶酶基因（agaA）。一个2，985个核苷酸的开放阅读框产生由成熟蛋白琼脂糖酶0107（975个氨基酸残基，分子量为105，271）和N末端20个氨基酸残基的信号肽组成的初级翻译产物。与天蓝色链霉菌和大西洋假单胞菌的琼胶酶0107推导的氨基酸序列的比较表明，这些酶有两个共同的区域。在大肠杆菌中表达的AgaA蛋白具有琼胶酶活性。琼脂酶0107不仅水解琼脂糖，还水解新琼脂四糖[O-3，6-脱水-α-L-吡喃半乳糖基（1->3）-O-β-D-吡喃半乳糖基（1->4）-O-3，6-脱水-α-L-吡喃半乳糖基（1->3）-D-半乳糖]，产生新琼脂二糖[O-3，6-脱水-α-L-吡喃半乳糖基（1->3）-D-半乳糖]。这是β-琼脂酶的一个非常独特的特性。
An agarase gene (agaA) was cloned from genomic DNA of Vibrio sp. strain JT0107. An open reading frame of 2,985 nucleotides gave a primary translation product composed of the mature protein, agarase 0107 (975 amino acid residues, with a molecular weight of 105,271) and a signal peptide of 20 amino acid residues at the N terminus. Comparison of the deduced amino acid sequence of agarase 0107 with those of Streptomyces coelicolor and Pseudomonas atlantica suggests that these enzymes share two regions in common. The AgaA protein which was expressed in Escherichia coli had the agarase activity. Agarase 0107 hydrolyzes not only agarose but also neoagarotetraose [O-3,6-anhydro-alpha-L-galactopyranosyl (1-->3)-O-beta-D-galactopyranosyl(1-->4)-O-3,6-anhydro-alpha-L-galact opy ranosyl (1-->3)-D-galactose] to yield neoagarobiose [O-3,6-anhydro-alpha-L-galactopyranosyl(1-->3)-D-galactose]. This is a quite unique characteristic for a beta-agarase.