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Updated: Jul 30, 2026

High Precision FRET at Single-molecule Level for Biomolecule Structure Determination
11:24

High Precision FRET at Single-molecule Level for Biomolecule Structure Determination

Published on: May 13, 2017

カップリングコヒーレンスによって,タンパク質の電子移転における構造感度が区別される

Tatiana R Prytkova1, Igor V Kurnikov, David N Beratan

  • 1Departments of Chemistry and Biochemistry, Duke University, Durham, NC 27708, USA.

Science (New York, N.Y.)
|February 3, 2007
PubMed
まとめ

サイトクロームb562の誘導体における電子トンネリングは,2つの異なる結合限界を示している:構造に無感な複数の経路の体制と構造に依存する単一経路の限界,電子伝送速度の記述を統一する.

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NMR Spectroscopy: Spin–Spin Coupling01:08

NMR Spectroscopy: Spin–Spin Coupling

The spin state of an NMR-active nucleus can have a slight effect on its immediate electronic environment. This effect propagates through the intervening bonds and affects the electronic environments of NMR-active nuclei up to three bonds away; occasionally, even farther. This phenomenon is called spin–spin coupling or J-coupling. Coupling interactions are mutual and result in small changes in the absorption frequencies of both nuclei involved. While nuclei of the same element are involved...
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Coupling interactions are strongest between NMR-active nuclei bonded to each other, where spin information can be transmitted directly through the pair of bonding electrons. While nuclei polarize their electrons to the opposite spins, the bonding electron pair has opposite spins. Configurations with antiparallel nuclear spins are expected to be lower in energy. When coupling makes antiparallel states more favorable, J is considered to have a positive value. The one-bond coupling constant, 1J,...
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