相关实验视频
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11:37
Analyzing Protein Dynamics Using Hydrogen Exchange Mass Spectrometry
Published on: November 29, 2013
细胞因子 tautomers 的兴奋状态动态
Kyriaki Kosma1, Christian Schröter, Elena Samoylova
1Max Born Institute, Max-Born-Strasse 2A, D-12489, Berlin-Adlershof, Germany.
Journal of the American Chemical Society
|October 31, 2009
概括
研究人员研究了和醇细胞因子分子在暴露于光线后如何放松. 生物相关的型表现出复杂的放松,而型表现出更简单的内部转化过程.
科学领域:
- 摄影化学的使用.
- 分子动力学分子动力学
- 量子化学 是一个量子化学.
背景情况:
- 氨酸是一种基本的核基,存在于不同的分体形式,包括和.
- 了解这些体的兴奋状态动态对于它们的生物功能和光稳定性至关重要.
研究的目的:
- 为了研究和阐明光激发的基托和醇/基托-伊米诺细胞因子 tautomers 的放松动态.
- 为了区分生物学上相关的酸与醇/酸胺酸的放松路径和寿命.
主要方法:
- 超快速光谱学被用来探测细胞因子 tautomers 的兴奋状态演变.
- 光刺激是在260-290nm波长范围内进行的.
- 实验结果与使用ab initio方法的理论计算进行了比较.
主要成果:
- 基托 tautomer 呈现出三种不同的放松短暂,寿命从 femtoseconds 到数百 picoseconds.
- 基托形式的这些短暂物被归因于内部转换和兴奋状态的分离.
- 乙醇或-氨基基因子 tautomer 显示只有两个短暂的 (femtosecond 和 picosecond 寿命),分配给内部转换.
结论:
- 这项研究揭示了基托和埃诺尔/基托-伊米诺细胞因子之间的光放松动态的显著差异.
- 基托 tautomer 的复杂动力学涉及内部转换和兴奋状态 tautomerization.
- 这些发现提供了关于细胞因子光化学的宝贵见解,与理论预测一致.
相关概念视频
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Selection Rules: Photochemical Activation
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01:18Aromatic Hydrocarbon Cations: Structural Overview
Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
Removing one hydrogen from the intervening CH2 group with both...
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01:26Thermal and Photochemical Electrocyclic Reactions: Overview
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00:52¹H NMR of Conformationally Flexible Molecules: Temporal Resolution
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01:14Keto–Enol Tautomerism: Mechanism
The keto and enol forms are known as tautomers and they constantly interconvert (or tautomerize) between the two forms under acid or base catalyzed conditions. Both the reactions involve the same steps—protonation and deprotonation— although in the reverse order.
02:37Disubstituted Cyclohexanes: cis-trans Isomerism
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In cyclohexane, the substituents can occupy different positions generating distinct isomers.
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