Environment-Sensitive Fluorescent Labelling of Peptides by Luciferin Analogues.
Int J Mol Sci
; 22(24)2021 Dec 10.
Article
in En
| MEDLINE
| ID: mdl-34948103
ABSTRACT
Environment-sensitive fluorophores are very valuable tools in the study of molecular and cellular processes. When used to label proteins and peptides, they allow for the monitoring of even small variations in the local microenvironment, thus acting as reporters of conformational variations and binding events. Luciferin and aminoluciferin, well known substrates of firefly luciferase, are environment-sensitive fluorophores with unusual and still-unexploited properties. Both fluorophores show strong solvatochromism. Moreover, luciferin fluorescence is influenced by pH and water abundance. These features allow to detect local variations of pH, solvent polarity and local water concentration, even when they occur simultaneously, by analyzing excitation and emission spectra. Here, we describe the characterization of (amino)luciferin-labeled derivatives of four bioactive peptides the antimicrobial peptides GKY20 and ApoBL, the antitumor peptide p53pAnt and the integrin-binding peptide RGD. The two probes allowed for the study of the interaction of the peptides with model membranes, SDS micelles, lipopolysaccharide micelles and Escherichia coli cells. Kd values and binding stoichiometries for lipopolysaccharide were also determined. Aminoluciferin also proved to be very well-suited to confocal laser scanning microscopy. Overall, the characterization of the labeled peptides demonstrates that luciferin and aminoluciferin are previously neglected environment-sensitive labels with widespread potential applications in the study of proteins and peptides.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Peptides
/
Fluorescent Dyes
/
Luciferins
Type of study:
Diagnostic_studies
Language:
En
Journal:
Int J Mol Sci
Year:
2021
Document type:
Article
Affiliation country:
Italy