权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Metal binding ability of vanabins and the redox reaction of vanadium

钒的金属结合能力和钒的氧化还原反应

基本信息

批准号：
18570070
负责人：
UEKI Tatsuya
金额：
$ 2.59万
依托单位：
Hiroshima University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2006
资助国家：
日本
起止时间：
2006 至 2007
项目状态：
已结题

项目摘要

The purpose of this study is to reveal the metal binding domains of a vanadium-binding protein Vanabin2, to reveal the relationship between disulfide banding structures and metal binding, and to reveal the redox reaction and biological function of vanadium in ascidians.1. Several mutant vanabins were constructed and their metal binding ablitily was assayed. lysine residues located near the 64th histidine are important for high affinity binding of vanadium(IV).2. Serine substitutions of cysteines caused structural instability and degradation of the mutant proteins. Especially fifth disulfide bonding was most important for structural stability These mutation did not affect the binding of vanadium.3. Metal selectivity of glutathione transferase (AsGST) was assayed. AtpH4.5, AsGST bound specifically to iron (III), copper(II) and vanadium (IV).4. When Vanabin2 was treated with several reductants in vitro, intermediate structures were observed. Relationship between the reduction of vanadium(V) and the redox of disulfide bonds in Vanabin2 was assessed in vitro. Redox intermediate structure of Vanabin2 was suggested.5. By micro array analysis on Ciona intestinalis, genes whose expression was affected by the addition of vanadium(IV) and vanadium(V) ions were explored. Basic sugar metabolism pathways were not affected, except for pentose phosphate pathway. In addition, enzymes in glutathione metabolism were affected.

本研究的目的是揭示钒结合蛋白Vanabin2的金属结合结构域，揭示二硫带结构与金属结合的关系，揭示钒在海鞘中的氧化还原反应和生物学功能。构建了几个突变体vanabins，并测定了它们的金属结合能力。位于第64个组氨酸附近的赖氨酸残基对于钒（IV）的高亲和力结合是重要的。半胱氨酸的丝氨酸取代导致突变蛋白的结构不稳定和降解。特别是第五二硫键对结构稳定性最重要，这些突变对钒的结合没有影响。测定了谷胱甘肽转移酶（AsGST）的金属选择性。AtpH4.5， AsGST特异性结合铁（III），铜（II）和钒（IV）。在体外用多种还原剂处理Vanabin2时，观察到中间结构。体外研究了Vanabin2中钒(V)的还原与二硫键氧化还原的关系。提出了Vanabin2的氧化还原中间结构。通过微阵列分析，探索了添加钒（IV）和钒(V)离子后，对鸡爪草（Ciona ninteinalis）基因表达的影响。除戊糖磷酸途径外，基本糖代谢途径未受影响。此外，谷胱甘肽代谢酶也受到影响。