A Glutathione-Responsive Short Sequence of Metal-Organic Complex Array

Area of Science:

• Coordination chemistry
• Supramolecular chemistry
• Biomaterials science

Background:

• Metal-organic complex arrays (MOCAs) are emerging materials with tunable properties.
• Biothiols, such as glutathione (GSH), play critical roles in biological systems.
• Understanding molecular interactions is key to developing new functional materials.

Purpose of the Study:

• To investigate the interaction between a specific MOCA sequence (RPtRRu, denoted as 1_Cl) and glutathione (GSH).
• To characterize the self-assembly behavior of the MOCA-GSH complex.
• To examine the effect of GSH binding on the MOCA's interaction with DNA.

Main Methods:

• Synthesis and characterization of the RPtRRu MOCA (1_Cl).
• Spectroscopic and microscopic analysis of the interaction between 1_Cl and GSH.
• Investigation of the binding of 1_Cl and its GSH adduct (1_GS) to calf thymus DNA using techniques like circular dichroism.

Main Results:

• The MOCA (1_Cl) selectively binds glutathione (GSH) to form a 1:1 complex (1_GS).
• Upon GSH binding, 1_GS undergoes supramolecular polymerization, forming nanofibrous assemblies via double-salt-bridge structures.
• The presence of GSH significantly enhances the conformational changes induced by the MOCA on calf thymus DNA.

Conclusions:

• The RPtRRu MOCA exhibits a unique response to GSH, leading to self-assembled nanofiber formation.
• GSH binding modulates the MOCA's interaction with DNA, suggesting potential applications in biomolecular recognition and sensing.
• This study highlights the potential of MOCAs as responsive materials in biological contexts.