Cloning and nucleotide sequencing of genes encoding Mn-superoxide dismutase and class II fumarase from Thermus aquaticus YT-1
Cloning and nucleotide sequencing of genes encoding Mn-superoxide dismutase and class II fumarase from Thermus aquaticus YT-1
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DOI：
10.1016/s0922-338x(98)80028-7
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发表时间：
1998-01-01
期刊：
影响因子：
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通讯作者：
Kaminogawa, S
中科院分区：
文献类型：
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作者：
Motoshima, H;Minagawa, E;Kaminogawa, S
测定了水生栖热菌YT-1锰超氧化物歧化酶（MnSOD）基因Pst Ⅰ-Hind Ⅲ DNA片段的6955 bp序列。该基因（sod）编码由204个氨基酸残基组成的多肽（不含起始甲硫氨酸的成熟酶），计算的Mr为22，773。推导的sod基因的氨基酸序列与嗜热栖热菌HB 8的同源性为92%。sod基因在大肠杆菌中得到了高效表达，并产生了一种热稳定的活性酶。在MnSOD基因上游91 bp处发现一个编码富马酸酶的开放阅读框，呈串联形式。fum基因编码由466个氨基酸残基组成的多肽，计算的M-r为50，950。推导的fum基因产物的氨基酸序列与大肠杆菌fumC的氨基酸序列相似。coli（57%的同源性），表明该基因编码一种II类淀粉酶。
A 6955-bp sequence of a PstI-HindIII DNA fragment containing the manganese-superoxide dismutase (MnSOD) gene of Thermus aquaticus YT-1 was determined. The gene (sod) encoded a polypeptide consisting of 204 amino acid residues (the mature enzyme without the initiation methionine) with a calculated Mr of 22,773. The deduced amino acid sequence of the sod gene showed 92% identity to that of Thermus thermophilus HB8 determined chemically. The sod gene was well expressed in Escherichia coli and a heat-stable active enzyme was produced. An open reading frame encoding fumarase was found 91bp upstream of the MnSOD gene in tandem form. The fum gene encoded a polypeptide consisting of 466 amino acid residues with a calculated M-r of 50,950. The deduced amino acid sequence of the fum gene product has similarity to that of the fumC of E. coli (57% identity), suggesting that this gene encodes a class II type fumarase.