Phosphorylation state-responsive lanthanide peptide conjugates: a luminescence switch based on reversible complex...

Area of Science:

• Biochemistry
• Chemical Biology
• Analytical Chemistry

Background:

• Peptide phosphorylation is a critical regulatory mechanism in cellular processes.
• Developing sensitive tools to study dephosphorylation is essential for understanding signal transduction pathways.
• Existing methods for detecting dephosphorylation can be complex or lack sensitivity.

Purpose of the Study:

• To develop a novel luminogenic probe for detecting peptide dephosphorylation.
• To investigate the mechanism of luminescence enhancement in the probe.
• To demonstrate the probe's effectiveness in monitoring phosphatase activity in vitro.

Main Methods:

• Synthesized a peptide-based luminogenic probe incorporating a tryptophan residue and a DTPA chelate.
• Utilized terbium(III) (Tb(3+)) for luminescence detection.
• Investigated the probe's response to varying phosphorylation states of serine and tyrosine residues.
• Proposed a mechanistic model involving monomeric and dimeric lanthanide species.

Main Results:

• The developed probe exhibits luminescence enhancement upon peptide dephosphorylation.
• The probe's luminescence is sensitive to the phosphorylation state of serine or tyrosine residues.
• A mechanistic model explaining luminescence modulation via lanthanide species interconversion was proposed.
• The probe effectively functions as an optical switch for phosphatase-catalyzed dephosphorylation.

Conclusions:

• A novel luminogenic probe for peptide dephosphorylation has been successfully developed.
• The probe's mechanism relies on phosphorylation-dependent modulation of lanthanide species.
• This tool provides an effective method for in vitro detection of phosphatase activity.