The Biochemistry and Metabolic Networking of Leucine Catabolism

9507549 Wurtele维持同化物和催化剂之间的平衡对植物化学物质的净生物合成至关重要。 这种代谢平衡在幼苗发育期间尤其明显，此时大量的种子储备（脂质、蛋白质和碳水化合物）被分解代谢。 然后，所产生的中间体被用作新植物化学物质生物合成的底物，或者它们被呼吸以产生支持生物合成反应的ATP。 这些代谢相互转化需要许多拮抗过程的协调作用和调节。 该奖项将研究大豆和拟南芥幼苗中亮氨酸的催化作用和随后衍生碳的利用，作为生物体如何协调复杂的相互关联的代谢途径以实现生物分子净相互转化的一个例子。 在植物中，亮氨酸的催化作用被认为是在线粒体中发生的，通过一系列反应，这些反应与甲羟戊酸代谢为非类异戊二烯化合物的途径部分相同。 因此，由亮氨酸和甲羟戊酸形成的乙酰辅酶A可以进一步代谢用于呼吸、脂肪生成和脂肪生成。 这些研究将确定以前未知的线粒体代谢过程，并开始指出它们如何与其他细胞器中的代谢相互作用。 对分解代谢过程的理解最终将使我们更好地理解植物是如何在同化和同化之间保持平衡的。 了解这种平衡是如何调节的，可能会为改善农业生产开辟新的、尚未预见的途径。

9507549 Wurtele The maintenance of a balance between anabolism and catabolism is crucial to the net biosynthesis of phytochemicals. This metabolic balance is particularly evident during seedling development when large quantities of seed reserve (lipids, proteins, and carbohydrates) are catabolized. The resultant intermediates are then utilized as substrates for the biosynthesis of new phytochemicals, or they are respired to generate ATP, which supports the biosynthetic reactions. These metabolic interconversions require the coordinate action and regulation of many antagonistic processes. This award will study the catabolism of leucine and subsequent utilization of the derived carbon in young seedlings of soybean and Arabidopsis, as an example of how organisms coordinate complex interconnected metabolic pathways to achieve net interconversions of biomolecules. In plants, the catabolism of leucine is thought to occur in mitochondria, via a set of reactions which are partly in common with a pathway by which mevalonate may be metabolized to non-isoprenoid compounds. Acetyl-CoA thus formed from leucine and mevalonate can be further metabolized for respiration, gluconeogenesis, and lipogenesis. These investigations will define previously unknown mitochondrial metabolic processes and begin to indicte how they interface with metabolism in other organelles. The understanding of catabolic provesses will ultimately provide a better understanding of how plants maintain a balance between anabolism and catabolism. Comprehension of how this balance is regulated may open new, as yet unforeseen, avenues to the improvement of agricultural production.