COMPUTATIONAL METHODS FOR ANALYSIS OF INTERMEDIARY METABOLISM

中间代谢分析的计算方法

• 批准号: 6205880
• 负责人: F MARK JEFFREY
• 金额: $ 6.95万
• 依托单位: UT SOUTHWESTERN MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-08-15 至 2000-08-14
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6205880
• 关键词: Mammalia; animal tissue; biomedical resource; cardiovascular system; computers; human tissue; liver; nuclear magnetic resonance spectroscopy; statistics /biometry; technology /technique

This project involves the development of mathematical models to estimate the flux through different pathways using isotopomer analysis and 13C NMR data. Three programs are under development: tcaSIM, a simulation of the citric acid cycle and related pathways which generates 13C isotopomer data for use in the design of experiments; tcaCALC, a model which estimates relative pathway fluxes from NMR spectra obtained at metabolic and isotopic steady state; and tcaFLUX, a kinetic analysis of the citric acid cycle which allows measurement of absolute flux from systems at metabolic, but not isotopic, steady state. There has been much progress in the development of the kinetic analysis. It has been applied to multiplet data and fractional enrichment data collected from intact hearts and after freeze-clamping. A number of different substrate groups were examined. The model can be used to estimate citric acid cycle activity, the exchange between citric acid cycle intermediates and amino acids (which will include transportation between different cellular compartments), the contribution of labeled substrate to acetyl-CoA, and anaplerosis. The citric acid cycle rate determined by the model was used to estimate oxygen consumption; the values obtained were similar to those measured directly. It has been found that the use of multiplet data along with standard fractional carbon enrichments in this analysis is beneficial, reducing the correlation between parameters that otherwise exists. There has also been success with the application of data available from GCMS to isotopomer analysis. A Finnegan GCQ bench-top GCMS with tandem mass spectrometry capability is in use. This allows the investigator to acquire, in addition to standard full-scan mass spectra, mass spectra of parent ions which have been fragmented after inducing collisions with the carrier gas. The mass spectra of these fragments give additional information on the isotopomers present in the metabolite mixture. Using the methyl-8 derivative of glutamate isolated from hearts perfused under a variety of conditions, such data was analyzed in a similar fashion to NMR multiplet data to determine substrate utilization and anaplerosis. The results were very similar to those obtained using NMR data, indicating that this technique will be useful as a more-sensitive, complementary approach to NMR. (Core 3) REPORT PERIOD: (09/01/97-08/31/98)

该项目涉及数学模型的开发 使用同位素异构体分析估计通过不同途径的通量 和 13C NMR 数据。 三个项目正在开发中：tcaSIM、a 模拟柠檬酸循环和相关途径 生成 13C 同位素异构体数据用于实验设计； tcaCALC，一种根据 NMR 估算相对路径通量的模型 在代谢和同位素稳态下获得的光谱；和 tcaFLUX， 柠檬酸循环的动力学分析可进行测量 代谢系统的绝对通量，但不是同位素稳定的 状态。 动力学的发展取得了很大进展 分析。 它已应用于多重数据和分数 从完整的心脏和之后收集的富集数据 冷冻钳制。 许多不同的底物组 检查了。 该模型可用于估计柠檬酸循环 活性，柠檬酸循环中间体之间的交换 氨基酸（其中包括不同氨基酸之间的运输） 细胞区室），标记底物的贡献 乙酰辅酶A和回补。 柠檬酸循环速率由下式确定 该模型用于估计耗氧量；获得的值 与直接测量的结果相似。 已经发现， 使用多重数据和标准碳分数 此分析中的丰富内容是有益的，减少了相关性 之间否则存在的参数。 也已经取得了成功 将 GCMS 提供的数据应用到同位素异构体 分析。 配备串联质谱仪的 Finnegan GCQ 台式 GCMS 能力正在使用中。 这使得研究者能够获得 除了标准全扫描质谱外，母体质谱 与诱导碰撞后已碎裂的离子 载气。 这些片段的质谱给出了额外的 有关代谢物混合物中存在的同位素异构体的信息。 使用从心脏中分离的谷氨酸甲基 8 衍生物 在各种条件下灌注，对这些数据进行分析 与 NMR 多重数据类似的方式来确定底物 利用和回补。 结果与那些非常相似 使用核磁共振数据获得，表明该技术将是有用的 作为 NMR 的一种更灵敏的补充方法。 （核心3）报告 期间: (09/01/97-08/31/98)