Alpha-carboxy nucleoside phosphonates as universal nucleoside triphosphate mimics

Area of Science:

• Biochemistry
• Molecular Biology
• Medicinal Chemistry

Background:

• Polymerases utilize a conserved, negatively charged amino acid motif for Mg(2+) cation-dependent nucleotide incorporation.
• This Mg(2+) binding is crucial for the catalytic activity of polymerases in nucleic acid synthesis.

Purpose of the Study:

• To design and characterize a novel class of polymerase inhibitors based on a nucleoside monophosphonate scaffold.
• To investigate the mechanism of action of α-carboxy nucleoside phosphonates (α-CNPs) as polymerase inhibitors.

Main Methods:

• Kinetic, biochemical, and crystallographic studies were performed using HIV-1 reverse transcriptase.
• Mechanism of action studies involved analyzing the binding interactions and inhibitory effects of α-CNPs.

Main Results:

• α-CNPs were recognized by polymerases and mimicked deoxy-nucleoside triphosphate (dNTP) binding through specific interactions.
• α-CNPs chelate Mg(2+) ions, bind directly to the active site, and reversibly inhibit polymerase activity without incorporation.
• α-CNPs also interact with allosteric Mg(2+)-dNTP-binding sites in metabolically regulated enzymes.

Conclusions:

• α-CNPs represent a novel class of non-nucleoside inhibitors that do not require metabolic activation.
• These compounds offer a versatile platform for developing targeted inhibitors of polymerases and related enzymes with therapeutic potential.