Study of a highly selective leaching of rare metals from seawater using biological functions

利用生物功能从海水中高选择性浸出稀有金属的研究

• 批准号: 11559014
• 负责人: MICHIBATA Hitoshi
• 金额: $ 9.02万
• 依托单位: Hiroshima University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-11559014/
• 关键词: Ascidian; Vanadium; Transition metals; Highly selective accumulation; Vanadium-binding proteins; Rare metals; 金属イオン; 海水; 選択的分取; 吸着剤; 遺伝子クローニング

Rare metals such as vanadium, cobalt, manganese, nickel and molybdenum are dissolved in sea water at very low levels. Ascidians, especially belonging to the Phlebobranchia, are known to selectively accumulate high levels of vanadium. We previously extracted vanadium-associated proteins from vanadium-containing blood cells (vanadocytes) of Ascidia sydneiensis samea. In this study, full-length of cDNAs, encoding 12.5 kDa and 15 kDa vanadium-associated proteins (designated newly as Vanabin), respectively, which might have a clue to resolve the mechanism of vanadium accumulation, was analyzed. As a result, Vanabin was disclosed to consist of about 120 amino acids in which the content of cysteine residues is very high and to be a novel protein having α-helix. Recombinant Vanabin was found to bind with about 20 atoms of vanadium ions and its binding constant is 10^<-7>M. Metal binding sites in progress.Recently, it has been disclosed that 12.5 kDa Vanabin binds with about 10 atoms of vanadium in the +4 oxidation state, 15 kDa Vanabin does not bind with iron ions or copper ions and copper ions inhibits the binding of Vanabin with vanadium ions, competitively.

稀有金属，如钒、钴、锰、镍和钼在海水中的溶解程度很低。海鞘类，特别是属于白鳍纲的海鞘类，已知会选择性地积累高水平的钒。我们先前从黑腹水母的含钒血细胞(钒细胞)中提取了与钒相关的蛋白。本研究对编码12.5 kDa和15 kDa钒相关蛋白(新命名为Vanabin)的全长基因进行了分析，这些基因可能为解决钒的积累机制提供线索。结果表明，Vanabin由约120个氨基酸组成，其中半胱氨酸残基含量很高，是一种新的具有α-螺旋的蛋白质。研究发现，重组钒与约20个钒离子结合，结合常数为10；-7~gt；M。最近发现12.5 kDa钒以+4氧化态与约10个钒原子结合，15 kDa钒不与铁离子或铜离子结合，铜离子竞争性抑制钒离子与钒离子的结合。

项目成果

Michibata, H.: "The Biology of Ascidian."H.Sawada, H.Yokosawa and C.C.Lambert, eds. Springer-Verlag Tokyo. 366-373 (2001)

Michibata, H.：“海鞘生物学”。H.Sawada、H.Yokosawa 和 C.C.Lambert，编辑。

Michibata, H.: "Vanadocyte is a cell holding the key to resolve the highly selective accumulation and reduction of vanadium in ascidians"Microscop. Res.Technol.. (in press). (2002)

Michibata, H.：“钒细胞是解决海鞘中钒高度选择性积累和还原问题的关键细胞”显微镜。

Michibata, H.: "Physiological finction of selective accumulation of vanadium in ascidians from sea water and its application"Nihon Kaisuigakkaishi. 53. 248-257 (1999)

Michibata, H.：“海水中海鞘选择性积累钒的生理功能及其应用”N​​ihon Kaisuigakkaishi。

Michibata, H.: "Molecular biological approaches to the accumulation and reduction of vanadium by ascidians"Coord.Chem.Rev.. (in press). (2002)

Michibata, H.：“海鞘积累和减少钒的分子生物学方法”Coord.Chem.Rev..（出版中）。

Ueki,T.: "Subunit C of the vacuolar-type ATPase from the vanadium-rich ascidians, Ascidia sydneiensis samea, rescued the pH sensitivity of yeast vma5 mutants."Marine Biotech.. (in press). (2001)

Ueki,T.：“来自富含钒的海鞘（Ascidia sydneiensis Samea）的液泡型 ATP 酶的 C 亚基，挽救了酵母 vma5 突变体的 pH 敏感性。”海洋生物技术..（出版中）。