Related Experiment Video
Updated: Jun 23, 2026

Modification and Functionalization of the Guanidine Group by Tailor-made Precursors
Published on: April 27, 2017
De novo sequence analysis of N-terminal sulfonated peptides after in-gel guanidination
Kjell Sergeant1, Jozef Van Beeumen, Bart Samyn
1Laboratory of Protein Biochemistry and Protein Engineering, Department of Biochemistry, Physiology and Microbiology, Ghent University, K.L. Ledeganckstraat 35, B-9000 Gent, Belgium.
Abstract:
In this protocol, we describe an approach in which two-dimensional electrophoresis (2DE)-separated proteins are guanidinated in-gel prior to enzymatic cleavage. In contrast to previously described techniques, this procedure allows the extracted tryptic peptides to be N-terminally sulfonated without any further sample purification. The protocol was applied on a proteomic study of 2DE-separated proteins from Halorhodospira halophila, an extremophilic eubacterium with an unsequenced genome at the moment of analysis.
Related Concept Videos
Maxam-Gilbert Sequencing
Challenges of the Maxam-Gilbert Method
The...
SDS-PAGE
A variation of gel electrophoresis, termed polyacrylamide gel electrophoresis (PAGE), is commonly used for separating proteins according to their molecular size by passing them through a polyacrylamide gel. Because of the varying charges associated with amino acid side chains, PAGE can be used to separate intact proteins...

