一种用于蛋白质碳同位素分析的新方法
1Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, CA 94550.
Science (New York, N.Y.)
|February 1, 1991
概括
与氨基酸的ninhydrin反应使蛋白质的精确碳同位素分析成为可能. 这种方法可靠地追溯到古老的骨,有助于理解饮食中的碳,在生物化学和全球碳研究中具有更广泛的应用.
科学领域:
- 生物地质化学生物地质化学
- 分析化学 分析化学
- 古蛋白质组学是古蛋白质组学.
背景情况:
- 对蛋白质进行精确的碳同位素分析对于古食重建和了解全球碳循环至关重要.
- 现有的分离与蛋白质结合的碳的方法往往容易受到污染,使同位素测量变得复杂.
- 九水素反应提供了一种新的方法,可以从蛋白质材料中选择性地提取特定的碳分数.
研究的目的:
- 评估ninhydrin反应的有效性,以从蛋白质中分离与结合的碳,进行同位素分析.
- 用这种方法评估放射性碳年代测定和从蛋白质中获得的稳定碳同位素数据的可靠性.
- 探索ninhydrin反应在生物化学追踪和全球碳预算研究中的潜在应用.
主要方法:
- 利用ninhydrin反应从蛋白质样本中的结碳中选择性地提取二氧化碳.
- 将该方法应用于用于放射性碳测年的古老骨样本.
- 在提取的二氧化碳中分析稳定的碳同位素比率 (δ13C).
主要成果:
- 宁氨酸反应成功分离了与结合的碳,最大限度地减少了污染物.
- 使用这种方法对古代骨进行放射性碳测年,可以获得可靠的年龄估计.
- 稳定碳同位素数据表明,需要重新评估当前的饮食重建模型.
结论:
- 九水素反应为分析蛋白质中的碳同位素提供了一个强大的方法,这对于古食和生物地球化学研究至关重要.
- 这种技术为古老生物材料提供了可靠的放射性碳测年法.
- 该方法的适用性扩展到生物化学追踪和全球碳研究,并有可能用于其他同位素分析.
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