Metabolic Control Analysis

人们普遍认为， 代谢途径是已知的， 这些途径发生在非常有限数量的“速率限制” 步这一概念导致了药物的设计，以改变 这些“限速酶”的动力学。这也导致了 改变代谢途径， 利用分子生物学的技术。沮丧 在许多情况下，这种干预措施往往不能改变 研究中的路径。这些失败导致了 意识到对途径通量的“控制”分布在许多人中， 代谢途径的酶，并且可以从酶变化到 酶取决于条件（Brand，M.蛋白质科学，6： 1368-1369，1997; Shulman，R.G. FASEB J. 258：255-258，1998）。 代谢控制理论早就预测了控制的分布 在途径的许多酶中（Veech，RL & Fell，D.A. Cell Biochem.和Function 14：229-236，1996）。但实际 论证和检验这些理论在技术上是困难的。 我们是第一个进行所需测量的实验室， 通量，每个步骤的动力学和热力学常数，以及 所有基板和产品所需的水平，使这种正式的 主要代谢途径中的通量控制分析（Kashiwaya， Y.等人，J.Biol.Chem.269：25502-25514，1994）。但 详细分析整个代谢途径是劳动密集型的 并且非常耗时。因此，在1997财年， 开发新的和更自动化的代谢物检测方法 分析，这将使我们能够执行所需的测量 用于以更快速的方式进行代谢控制分析。我们也 试图开发适合于细胞分析的微量方法， 培养，特别是神经细胞。我们将应用这些 新的方法来确定是否提供乙酰基单位神经 组织可以改变多种神经系统疾病的进程 包括酒精戒断综合症

It is widely believed that the steps in the major metabolic pathways are known and that the control of flux through these pathways occurs at a very limited number of "rate limiting" steps. This concept has lead to the design of drugs to alter the kinetics of these "rate limiting enzymes". It has also led to attempts to alter metabolic pathways by altering the amounts of rate limiting enzymes using the techniques of molecular biology. To the dismay of many, such interventions often fail to alter the rates of the pathways under study. These failures have led to an increased awareness that "control" of pathway flux is distributed among many enzymes of a metabolic pathway and can vary from enzyme to enzyme depending upon conditions (Brand, M. Protein Science, 6: 1368-1369, 1997; Shulman, R.G. FASEB J. 258: 255-258, 1998). Metabolic control theory had long predicted distribution of control among many enzymes of a pathway (Veech, R.L. & Fell, D.A. Cell Biochem. & Function 14: 229-236, 1996). However, actual demonstration and testing of such theories was technically difficult. We were the first laboratory to make the required measurements of flux, kinetic and thermodynamic constants of each step, and the levels of all substrates and products required to make such a formal analysis of flux control in a major metabolic pathway (Kashiwaya, Y. et al, J. Biol. Chem. 269: 25502-25514, 1994). However, the detailed analysis of an entire metabolic pathway was labor intenstive and extremely time consuming. Therefore during FY97 we began developing new and more automated methods of metabolite analysis which will allow us to perform the measurements required for metabolic control analysis in a more rapid manner. We are also attempting to develop micro methods suitable for analysis of cells in culture, and specifically neuronal cells. We will then apply these new methods to determine if the provision of acetyl units to neural tissue can alter the course of a variety of neurological conditions including alcohol withdrawal syndrome.