Related Experiment Video
Updated: May 27, 2026
07:31
Nitropeptide Profiling and Identification Illustrated by Angiotensin II
Published on: June 16, 2019
Identification of protein nitrosothiols using phosphine-mediated selective reduction
Sheng Li1, Hua Wang, Ming Xian
1Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27710, USA.
Nitric Oxide : Biology and Chemistry
|November 22, 2011
Summary
Researchers developed a new method using triphenylphosphine ester derivatives to detect S-nitrosation in proteins. This technique offers improved specificity and sensitivity for studying nitric oxide signaling pathways in complex biological samples.
Area of Science:
- Biochemistry
- Cell Biology
- Molecular Signaling
Background:
- S-nitrosation of cysteine residues regulates protein function and is a key mechanism in nitric oxide (NO) signaling.
- Existing methods, like the ascorbate-based biotin switch, face limitations in specificity and sensitivity for detecting S-nitrosothiols.
Purpose of the Study:
- To develop a novel, highly specific, and sensitive method for detecting protein S-nitrosation.
- To overcome the limitations of current techniques for analyzing nitric oxide signaling.
Main Methods:
- Utilized triphenylphosphine ester derivatives for selective reduction of S-nitrosothiol (SNO) bonds in proteins.
- Tagged reduced thiols with biotin or fluorescent maleimide reagents for detection.
- Applied the method to complex biological samples, including cell extracts and whole fixed cells.
Main Results:
- Triphenylphosphine ester derivatives specifically reduce SNO bonds without affecting protein disulfides or peroxide-modified thiols.
- The method demonstrated efficient reduction in both cell extracts and whole fixed cells.
- Successfully identified and labeled specific S-nitrosoproteins, particularly within the nuclear compartment, and showed S-nitrosoprotein formation in cells expressing inducible nitric oxide synthase.
Conclusions:
- Triphenylphosphine ester derivatives provide a reliable and specific tool for studying protein S-nitrosation.
- This new approach enhances the study of nitric oxide signaling and its role in cellular processes.
- The method is applicable to various biological contexts, including fixed cells and inducible nitric oxide synthase expression.
Related Concept Videos
02:33Preparation and Reactions of Thiols
Thiols are prepared using the hydrosulfide anion as a nucleophile in a nucleophilic substitution reaction with alkyl halides. For instance, bromobutane reacts with sodium hydrosulfide to give butanethiol.
01:27Phase I Reactions: Reductive Reactions
Phase I biotransformation reductive reactions are chemical processes that modify drugs by introducing or revealing polar functional groups via reduction. Enzymes called reductases catalyze these reactions, playing a pivotal role in drug metabolism by transforming lipophilic drugs into more polar, water-soluble metabolites for easy excretion. An essential type of reductive reaction is the carbonyl group reduction, where aldehydes and ketones are reduced to alcohols. An example is the...
01:29Preparation of Amines: Reduction of Oximes and Nitro Compounds
Oximes can be reduced to primary amines using catalytic hydrogenation, hydride reduction, or sodium metal reduction. The reduction of aliphatic and aromatic nitro compounds to primary amines takes place by either catalytic hydrogenation or by using active metals like Fe, Zn, and Sn in the presence of an acid.
Though catalytic hydrogenation can reduce nitrobenzenes, the reduction is nonselective in the presence of other functional groups. For instance, if nitrobenzene contains an aldehyde group,...
Though catalytic hydrogenation can reduce nitrobenzenes, the reduction is nonselective in the presence of other functional groups. For instance, if nitrobenzene contains an aldehyde group,...
00:55Nitriles to Amines: LiAlH4 Reduction
Nitriles are reduced to amines in the presence of strong reducing agents like lithium aluminum hydride through a typical nucleophilic acyl substitution. The reaction requires two equivalents of the reducing agent. The reducing agent acts as a source of hydride ions.
As shown below, the mechanism involves three steps. Firstly, the hydride ion acting as a nucleophile attacks the nitrile carbon to form an anion. In the second step, a second equivalent of the hydride ion attacks the anion to...
As shown below, the mechanism involves three steps. Firstly, the hydride ion acting as a nucleophile attacks the nitrile carbon to form an anion. In the second step, a second equivalent of the hydride ion attacks the anion to...
01:20Electrophilic Aromatic Substitution: Nitration of Benzene
The nitration of benzene is an example of an electrophilic aromatic substitution reaction. It involves the formation of a very powerful electrophile, the nitronium ion, which is linear in shape. The reaction occurs through the interaction of two strong acids, sulfuric and nitric acid.
01:13Preparation of Amines: Reduction of Amides and Nitriles
Nitriles can be reduced to primary amines using reducing agents like lithium aluminum hydride or catalytic hydrogenation. The reduction introduces an amino group with an extra carbon in the skeleton. Nitriles are formed from the reaction between alkyl halides and sodium cyanide through the SN2 mechanism. Primary alkyl halides are the preferred substrates to prepare nitriles.
Amides can be reduced to primary, secondary, and tertiary amines using catalytic hydrogenation, active metals like Fe,...
Amides can be reduced to primary, secondary, and tertiary amines using catalytic hydrogenation, active metals like Fe,...