Dynamics of DNA Polymerase Mechanisms

DNA polymerases orchestrate the faithful replication and repair of genomes through a coordinated sequence of substrate binding, chemical catalysis and product release. Central to this process are dynamic conformational changes—often described as open, ajar and closed states—that ensure correct nucleotide selection, catalyse phosphodiester bond formation and enable translocation along the DNA template. Metal-ion cofactors, typically magnesium, stabilise negative charges during phosphoryl transfer, while a subset of polymerases employs auxiliary ions to drive rate-limiting steps. Proofreading polymerases further remove misincorporated bases via an exonuclease activity, shuttling the primer terminus between active sites without full dissociation. Together, these dynamic events underpin replication fidelity, genome maintenance and the cellular response to DNA damage. Understanding these mechanisms holds global significance for elucidating disease-associated polymerase mutations, developing polymerase inhibitors for therapeutic use and engineering enzymes for biotechnological applications such as high-accuracy DNA synthesis and next-generation sequencing.

Research from Nature Portfolio

Recent studies have provided high-resolution snapshots of proofreading in human mitochondrial polymerase γ, uncovering a conserved bolt-action mechanism that shuttles mismatched bases from the polymerase to the exonuclease site without enzyme dissociation. Time-lapse crystallography of double-strand break repair polymerase μ has captured transient intermediates and identified a third product metal, illuminating how metal coordination and active-site rearrangements stabilise nucleotide insertion during non-homologous end joining. These advances link structural dynamics across distinct polymerase families, refining our understanding of how conformational transitions and metal-ion binding govern fidelity and catalytic efficiency.

Dynamics of DNA Polymerase Mechanisms publication trend

The graph below shows the total number of articles in dynamics of dna polymerase mechanisms across all publications each year (not limited to Nature Index journals).

Technical terms

DNA polymerase: Enzyme that catalyses strand-extension by adding deoxyribonucleotides to a primer bound to a DNA template.

Catalytic cycle: Ordered sequence of enzyme conformations and chemical steps from substrate binding to product release.

Proofreading: Exonucleolytic removal of incorrectly incorporated nucleotides to enhance replication accuracy.

Translocation: Movement of the polymerase forward by one nucleotide position along the DNA template following bond formation.

Conformational change: Structural rearrangement of the polymerase, especially between open and closed forms, that governs substrate selection and catalysis.

Metal-ion catalysis: Use of divalent cations, such as Mg2+, to stabilise transition states and negative charges during phosphoryl transfer.

Pyrophosphate (PPi): By-product released when a nucleotide is incorporated into the growing DNA strand.

Fidelity: Accuracy with which a polymerase selects and incorporates the correct nucleotide, critical for genomic stability.

References

1. The Structure of a High Fidelity DNA Polymerase Bound to a Mismatched Nucleotide Reveals an “Ajar” Intermediate Conformation in the Nucleotide Selection Mechanism*. Journal of Biological Chemistry (2011).
2. Structural basis for DNA proofreading. Nature Communications (2023).
3. Time-lapse crystallography snapshots of a double-strand break repair polymerase in action. Nature Communications (2017).
4. Unveiling the Mechanism of Deprotonation and Proton Transfer of DNA Polymerase Catalysis via Single‐Molecule Conductance. Advanced Science (2024).
5. A new paradigm of DNA synthesis: three-metal-ion catalysis. Cell & Bioscience (2016).
6. Revealing the role of the product metal in DNA polymerase β catalysis. Nucleic Acids Research (2017).