Mechanism of selective metal incorporation and cofactor maturation during tungsten cofactor biosynthesis

钨辅因子生物合成过程中选择性金属掺入和辅因子成熟的机制

• 批准号: 59983166
• 负责人: Professor Dr. Günter Schwarz
• 金额: --
• 依托单位: Institut für Biochemie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2007
• 资助国家: 德国
• 起止时间: 2006-12-31 至 2010-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/59983166?language=en
• 关键词: Mechanism; selective; metal; incorporation; cofactor

There are three biologically active hydrogenated pterins known in nature of which only one is associated with metals thus forming a prosthetic group referred to as molybdenum and tungsten cofactors. As molybdenum was first found to be associated with the pterin it was named molybdopterin but later it became evident that tungsten-containing enzymes use the same pterin scaffold to chelate the metal. The biosynthesis of these pterin-based metal cofactors has only been studied for molybdenum cofactors but it is believed that synthesis of the pterin is well conserved for both types of cofactors. However, nothing is known about the incorporation of tungsten into the respective cofactors. Tungsten cofactors belong to the family of bis-MPT cofactors whose final maturation is not even understood for molybdenum containing homologs. Therefore, we want to characterize the functions of three proteins (MoaB, MoeA1 and MoeA2) essential for metal insertion into tungsten cofactors of Pyrococcus furiosus thereby uncovering the molecular mechanism of tungsten cofactor synthesis. Comparison to E. coli proteins will enable us to determine a general mechanism of bis-MPT cofactor synthesis. Furthermore, nucleotide attachment in cofactors of the dimethyl sulfoxide family is poorly understood. Therefore, we will investigate guanyl transfer to the tungsten cofactor of P. furiosus formate dehydrogenase, which should uncover the general mechanism of bis-MPT guanine dinucleotide formation. Finally, tungsten-dependent enzymes will be reconstituted by a fully defined in vitro system.

已知有三种具有生物活性的氢化蝶呤，其中只有一种与金属结合，从而形成称为钼和钨辅因子的辅基。由于钼最初被发现与蝶呤相关，因此被命名为钼多蝶呤，但后来发现含钨酶使用相同的蝶呤支架来螯合金属。这些基于蝶呤的金属辅因子的生物合成仅针对钼辅因子进行了研究，但据信蝶呤的合成对于两种类型的辅因子都是保守的。然而，关于将钨结合到各自的辅因子中还一无所知。钨辅因子属于双MPT辅因子家族，其最终成熟甚至不了解含钼同系物。因此，我们希望表征三种蛋白质（MoaB，MoeA 1和MoeA 2）的功能，这三种蛋白质是金属插入到激烈火球菌的钨辅因子中所必需的，从而揭示钨辅因子合成的分子机制。比较E。大肠杆菌蛋白将使我们能够确定一个一般机制的双MPT辅因子的合成。此外，二甲基亚砜家族的辅因子中的核苷酸连接知之甚少。因此，我们将研究鸟苷酰转移到激烈丙酸杆菌甲酸脱氢酶的钨辅因子，这将揭示bis-MPT鸟嘌呤二核苷酸形成的一般机制。最后，钨依赖性酶将通过完全定义的体外系统进行重构。