BIOLOGICAL VANADIUM--MODELS OF STRUCTURE AND FUNCTION

钒在生物系统中的化学性质一直是个谜， 在它被发现的形式的条款和在它的 生物功能。 含钒的天然产物是 有文献记载，但这些化合物的功能活性未知。 钒在哺乳动物代谢中的潜在重要性 磷酰基转移酶和Na +-K + ATP酶抑制剂，如 哇巴因/胰岛素模拟物和甲状腺激素的产生是已知的。 第一个有文献记载的钒酶是从红色和棕色中分离出来的 藻类和地衣，并显示出催化卤过氧化物酶反应。 通过 产生挥发性大气。 万科也是一个重要的监管者 大气中的自然臭氧平衡。 Vanessa也是一个 植物代谢中一种重要的辅因子， 叶绿素生物合成和碳固定循环的调节剂， 光合作用的黑暗反应 建议的实验 下一个项目期间的重点是广泛阐明生物化学的 钒在四个主要领域： 通过设计新的钒来探讨钒卤代过氧化物酶的作用机理 增加过氧钒酸盐物质的稳定性的络合物， 配体和活化过氧化物的水解敏感性， 与卤化物和有机底物反应。 特别是，我们将重点 二过氧和过氧/羟胺的反应性 化合物. 研究钒酸盐催化肽光降解的机制， 评价钒螯合物的光化学降解， 已经表明是可光氧化的。 测试假设amavadin在真菌中的真正功能是作为一种 基本的卤素过氧化试剂。 定义钒的溅射、结构和溶液化学 植物铁载体复合物可能参与了 微量金属在植物中的螯合和运输。 总之，成功完成这些研究将提供一个 对钒的生物化学进行了广泛而详细的描述。 这一工作为进一步研究和了解 钒参与的复杂和不明确的过程 内源性（如甲状腺功能）或外源性（如胰岛素 模拟）在哺乳动物代谢中的作用。

The chemistry of vanadium in biological systems has been enigmatic both in terms of the terms of the forms in which it is found and in its biological functions. Natural products containing vanadium are documented, but no functional activities for these compounds are known. The potential importance of vanadium in mammalian metabolism as an inhibitor of phosphoryl transfer enzymes and Na+-K+ ATPases, as ouabain/insulin mimics and in the production of thyroid hormone is known. The first documented vanadium enzyme was isolated from red and brown algae and lichens and shown to catalyze a haloperoxidase reaction. By producing volatileatmosphere. Vanadium is also an important regulator of the natural ozone balance in the atmosphere. Vanadium is also an important cofactor in plant metabolism by acting as a key component in chlorophyll biosynthesis and a regulator of the carbon fixation cycle in the dark reactions of photosynthesis. The proposed experiments for the next project period focus on broadly elucidating the biochemistry of vanadium in four main areas: Probe the mechanism of vanadium haloperoxidase by designing new vanadium complexes that increases the stability of peroxovanadate species, reduce the hydrolytic susceptibility of the ligands and activate peroxide to react with halides and organic substrates. In particular, we will focus on the reactivity of diperoxo and peroxo/hydroxylamine containing compounds. Examine the mechanism of vanadate catalyzed peptide photodegradation by evaluating the photochemical degradation of vanadium chelates that we have shown are photooxidizable. Test the hypothesis that the true function of amavadin in fungi is as a rudimentary haloperoxidation reagent. Define the spatulation, structure and solution chemistry of vanadium phytosiderophore complexes that are probably involved in the sequestration and transport of trace metals into plants. Taken together, successful completion of these studies will provide a broad, yet detailed, description of the biological chemistry of vanadium. This work provides a foundation to study and to understand the more complex and poorly defined processes in which vanadium participates endogenously (as in thyroid function) or exogenously (as an insulin mimic) in mammalian metabolism.