Related Experiment Video
Updated: Jun 3, 2026

A New Approach for the Comparative Analysis of Multiprotein Complexes Based on 15N Metabolic Labeling and Quantitative Mass Spectrometry
Published on: March 13, 2014
A mass spectrometric analysis of 4-hydroxy-2-(E)-nonenal modification of cytochrome c
Xiaoxia Tang1, Lawrence M Sayre, Gregory P Tochtrop
1Department of Chemistry, Case Western Reserve University, Cleveland, OH 44106, USA.
Abstract:
Cytochrome c is a key mitochondrial respiratory protein that is particularly susceptible to modification during oxidative stress. The nature of this susceptibility is linked to the mitochondrial membrane being rich in esterified linoleic acid, which predisposes this organelle to the formation of lipid peroxidation products such as 4-hydroxy-2-(E)-nonenal (4-HNE). To better understand the nature of cytochrome c modification by 4-HNE, we initiated an in vitro study utilizing a combination of MALDI-TOF mass spectrometry, LC-ESI-MS/MS and isotope labeling to monitor 4-HNE modification of cytochrome c under various conditions. The overwhelming reaction observed is Michael addition by Lys side-chains in addition to the modification of His 33. While the Lys-4-HNE adducts were generally observed to be reversible, the 4-HNE-His 33 was observed to be stable with half of the formed adduct surviving the denaturation and proteolysis protocols used to generate proteolytic peptides for LC-ESI-MS/MS.
Related Concept Videos
Mass Spectrometry: Cycloalkene Fragmentation
Mass Spectrometry: Complex Analysis
GC–MS is a powerful hyphenated method commonly used in forensics and environmental...
Mass Spectrometry: Alkene Fragmentation
Mass Spectrometry: Aldehyde and Ketone Fragmentation
Mass Spectrometry: Cycloalkane Fragmentation
For example, cyclohexane molecular ions have a mass-to-charge ratio (m/z) of 84, which tends to produce a stronger signal than linear alkanes like hexane. This stability comes from...
Mass Spectrometry: Branched Alkane Fragmentation

