dinitrosyl-iron complex binding

Definition

Target type: molecularfunction

Binding to a dinitrosyl-iron complex. Nitric oxide (NO) is stored as dinitrosyl-iron complexes, which form spontaneously from Glutathione (GSH), S-nitrosoglutathione, and trace amounts of ferrous ions, or by reaction of iron-sulfur centers with NO. [GOC:BHF, PMID:10534443]

Dinitrosyl-iron complexes (DNICs) are a class of metalloproteins that play a crucial role in cellular signaling and redox homeostasis. Their molecular function centers around the coordination of two nitric oxide (NO) molecules to a ferrous iron ion (Fe2+), forming a complex with a characteristic dinitrosyl-iron unit. This unit exhibits a unique electronic structure and reactivity, which are critical for the various biological activities associated with DNICs.

The binding of NO to iron in DNICs is facilitated by the presence of a thiolate ligand, typically from cysteine residues in proteins. The resulting complex is characterized by a linear Fe-N-O arrangement, with the NO molecules occupying axial positions relative to the iron center. This arrangement imparts distinct spectroscopic properties to DNICs, which are commonly used for their detection and characterization.

One of the key molecular functions of DNICs is their ability to act as NO donors. The labile nature of the NO molecules in the complex allows for their release and transfer to other target molecules, such as proteins or enzymes. This NO delivery mechanism is essential for various cellular processes, including vasodilation, neurotransmission, and immune regulation.

Furthermore, DNICs possess redox activity, enabling them to participate in electron transfer reactions. The iron center in DNICs can undergo oxidation and reduction, facilitating the transfer of electrons between different molecules. This redox activity is crucial for maintaining cellular redox balance and protecting against oxidative stress.

In addition to their roles in NO delivery and redox regulation, DNICs are also involved in the modulation of enzyme activity. By interacting with specific proteins, DNICs can alter their enzymatic function. This modulation can range from activation to inhibition, depending on the specific enzyme and the nature of the DNIC interaction.

Overall, the molecular function of DNICs is multifaceted and essential for maintaining cellular homeostasis. Their ability to bind NO, donate NO, participate in redox reactions, and modulate enzyme activity underscores their crucial role in various physiological processes, including signal transduction, vascular homeostasis, and immune response.'
"

Proteins (1)

Compounds (10)