Modification of lysyl side chains using succinic anhydride

Area of Science:

• Biochemistry
• Protein Chemistry
• Analytical Chemistry

Background:

• Trypsin cleavage is crucial for protein sequencing.
• Lysine residues are common sites for trypsin digestion.
• Modifying lysine can alter enzymatic cleavage patterns and protein properties.

Purpose of the Study:

• To investigate the use of succinic anhydride for blocking lysine residues.
• To explore the impact of lysine succinylation on trypsin digestion specificity.
• To assess the utility of succinylation for protein solubilization and sequencing.

Main Methods:

• Chemical modification of protein lysine residues using succinic anhydride.
• Enzymatic digestion of succinylated proteins with trypsin.
• Analysis of peptide fragments for sequencing strategies.
• Solubility assessment of succinylated proteins at varying pH.

Main Results:

• Succinic anhydride effectively blocks the ε-amino group of lysine residues.
• Succinylating lysine redirects trypsin cleavage to arginine residues.
• Succinylation increases protein solubility, particularly at neutral to alkaline pH.
• The succinyl modification is stable under various conditions but can be reversed.

Conclusions:

• Lysine succinylation is a valuable strategy for selective trypsin digestion and protein sequencing.
• Succinylation enhances protein solubility, facilitating handling and analysis.
• This chemical modification offers a versatile tool in protein chemistry and analysis.