Iron superoxide dismutase from the archaeon Sulfolobus solfataricus:: average hydrophobicity and amino acid weight are involved in the adaptation of proteins to extreme environments
Iron superoxide dismutase from the archaeon Sulfolobus solfataricus:: average hydrophobicity and amino acid weight are involved in the adaptation of proteins to extreme environments
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DOI：
10.1016/s0167-4838(97)00105-2
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发表时间：
1997-11-14
期刊：
影响因子：
--
通讯作者：
Bocchini, V
中科院分区：
文献类型：
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作者：
Dello Russo, A;Rullo, R;Bocchini, V
嗜热嗜酸古细菌硫磺菌中的铁超氧化物歧化酶具有同二聚体结构，每个亚基的金属含量为 0.7 个铁原子。该酶对氰化物抑制不敏感，对 H2O2 失活敏感，是迄今为止已知的最耐热的 SOD，其半衰期在 100 摄氏度下为 2 小时。其主要结构是通过先进的质谱法和自动序列分析的有利组合确定的。纯化蛋白质裂解后获得的肽。该酶亚基由210个氨基酸残基组成，相对分子质量为24 112，不含半胱氨酸残基，具有较高的平均疏水性和氨基酸重量。反之亦然，嗜盐 SOD 的疏水性较低。因此，平均疏水性似乎与蛋白质对极端环境的适应有关。古菌和嗜热真细菌 SOD 一级结构的多重比对表明古菌 SOD 与嗜热真细菌 SOD 分开进化，并且嗜盐菌起源于与嗜热古菌不同的基因。 (C) 1997 Elsevier Science B.V.
The iron-superoxide dismutase in the thermoacidophilic archaeon Sulfolobus solfataricus has a homodimeric structure with a metal content of 0.7 atom of iron per subunit, The enzyme is insensitive to cyanide inhibition, sensitive to inactivation by H2O2 and is the most heat resistant SOD known so far being its half-life 2 h at 100 degrees C. Its primary structure was determined by a profitable combination of advanced mass spectrometry and automated sequence analysis of peptides obtained after cleavage of the purified protein. The enzyme subunit is composed of 210 amino acid residues accounting for a relative molecular mass of 24 112. It does not contain cysteine residues and has a high average of both hydrophobicity and amino acid weight. Vice versa, the hydrophobicity is lower in halophilic SODs. Therefore, it seems that the average hydrophobicity is involved in the adaptation of proteins to extreme environments. The multiple alignment of the primary structure of archaeal and thermophilic eubacterial SODs indicated that archaeal SODs evolved separately from the thermophilic eubacterial SODs and that halophiles originated from a gene different from that of thermophilic archaea. (C) 1997 Elsevier Science B.V.