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Related Experiment Video

Updated: May 13, 2026

Measurement of Heme Synthesis Levels in Mammalian Cells

Measurement of Heme Synthesis Levels in Mammalian Cells

Published on: July 9, 2015

Primary processes in heme-based sensor proteins.

Ursula Liebl¹, Jean-Christophe Lambry, Marten H Vos

¹Laboratory for Optics and Biosciences, CNRS, Ecole Polytechnique, Palaiseau, France.

Biochimica Et Biophysica Acta

|March 15, 2013

Summary

This summary is machine-generated.

Heme-based sensor proteins act as molecular switches, altering enzymatic activity upon gas ligand binding or dissociation. Their efficient ligand rebinding, or "ligand trap" property, helps stabilize signaling responses.

Keywords:

Heme protein Intra-protein signaling Molecular dynamics Primary process Ultrafast spectroscopy

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Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy

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Last Updated: May 13, 2026

Measurement of Heme Synthesis Levels in Mammalian Cells

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Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy

Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy

Published on: June 27, 2014

Area of Science:

Biochemistry
Molecular Biology
Biophysics

Background:

Heme-based sensor proteins are crucial molecular switches.
They modulate enzymatic activity via gas ligand (O2, NO, CO) binding to heme.
Signal transmission from heme to catalytic sites regulates protein expression.

Purpose of the Study:

Review emerging mechanisms in heme-based sensor proteins.
Highlight insights from experimental and simulation studies.
Focus on intra-protein signaling pathways and ligand dynamics.

Main Methods:

Ultrafast optical spectroscopy to study early signaling events.
Molecular dynamics simulations for timescale analysis.
Review of experimental studies on FixL, CooA, and soluble guanylate cyclase.

Main Results:

Heme-ligand bond photolability allows tracking of early signaling.
Ligand rebinding to heme is highly efficient in all sensors.
Internal ligand mobility in 6-coordinate proteins aids signal transfer.

Conclusions:

Heme-based sensors utilize a