Site-specific protein labeling with amine-containing molecules using Lactobacillus plantarum sortase

Area of Science:

• Biochemistry
• Molecular Biology
• Enzymology

Background:

• Protein modification with small molecules is crucial for biological research.
• Enzymatic methods offer site-specific modification due to substrate specificity.
• Sortase enzymes facilitate protein ligation via native peptide bonds.

Purpose of the Study:

• To demonstrate site-specific protein modification using Lactobacillus plantarum sortase.
• To characterize the substrate specificity of a novel L. plantarum sortase.
• To expand methods for conjugating amine-containing molecules to proteins.

Main Methods:

• Utilized enhanced green fluorescent protein (EGFP) as a model system.
• Engineered an EGFP tag with the LPQTSEQ recognition sequence for L. plantarum sortase.
• Conjugated an amine-containing biotin molecule to the tagged EGFP via enzymatic ligation.

Main Results:

• Developed a novel L. plantarum sortase with distinct substrate specificity compared to Staphylococcus aureus sortase.
• Achieved site-specific conjugation of a small molecule (biotin) to EGFP using the L. plantarum sortase.
• Demonstrated successful amine-directed protein modification via the LPQTSEQ tag.

Conclusions:

• Lactobacillus plantarum sortase provides a novel tool for site-specific protein modification.
• This method enables precise conjugation of amine-containing molecules to proteins.
• The findings expand the toolkit for protein engineering and chemical biology applications.