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An In Vitro Enzymatic Assay to Measure Transcription Inhibition by Gallium(III) and H3 5,10,15-tris(pentafluorophenyl)corroles
Published on: March 18, 2015
Corroles that bind with high affinity to both apo and holo transferrin
Adi Haber1, Hasmik Agadjanian, Lali K Medina-Kauwe
1Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Haifa 32000, Israel.
Journal of Inorganic Biochemistry
|January 9, 2008
Summary
Transferrin (Tf) binds water-soluble corroles and their metal complexes, including gallium and manganese derivatives. This interaction suggests potential for targeted drug delivery to cells expressing transferrin receptors.
Area of Science:
- Biochemistry
- Materials Science
- Nanotechnology
Background:
- Transferrin (Tf) is a key iron-transport protein.
- Corroles are porphyrin analogs with potential therapeutic applications.
- Targeting specific cell receptors is crucial for drug delivery.
Purpose of the Study:
- To investigate the binding interactions between transferrin and water-soluble corrole derivatives.
- To assess the potential of corrole-transferrin conjugates for targeted delivery to transferrin receptor-expressing cells.
Main Methods:
- Spectroscopic titrations (UV-Vis, fluorescence) were used to study binding.
- Fluorescence-based dilution experiments quantified binding affinities.
- Interactions were studied with both apo-transferrin (apoTf) and holo-transferrin (holoTf).
Main Results:
- Transferrin spontaneously binds corrole (1), gallium-corrole (1-Ga), and manganese-corrole (1-Mn) complexes.
- Very low dissociation constants were determined: <10(-9) M for corrole, 2 x 10(-7) M for 1-Ga with apoTf, and 3 x 10(-8) M for 1-Ga with holoTf.
- These affinities are relevant for physiological transferrin concentrations.
Conclusions:
- Corrole-transferrin conjugates can be formed due to spontaneous binding.
- The strong binding affinities support the potential utilization of these conjugates for targeted delivery.
- This approach could enable targeted delivery of corroles to cells expressing transferrin receptors.
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