DNA synthesis machinery and nucleotide metabolism pathway

The DNA synthesis machinery and nucleotide metabolism pathway represent a complex network of enzymes and regulatory proteins responsible for the production of nucleotide precursors and the replication of genetic material. This pathway includes the de novo and salvage synthesis of purines and pyrimidines, as well as the action of the replisome, which incorporates these nucleotides into new DNA strands during the S-phase of the cell cycle (StatPearls, 2023). Because malignant cells and certain pathogens exhibit accelerated proliferation, they are highly dependent on these pathways to maintain genomic integrity and support cell division (Nature Reviews Cancer, 2017). Therapeutic intervention typically involves antimetabolites, such as methotrexate or 5-fluorouracil, which inhibit key enzymes like dihydrofolate reductase or thymidylate synthase to starve cells of necessary building blocks (NIH, 2022). Additionally, nucleoside analogs can be incorporated into DNA to cause chain termination or lethal mutations, particularly in viral infections (PubMed, 2021). However, the lack of absolute specificity for diseased cells often leads to significant side effects in healthy, rapidly dividing tissues like the bone marrow and intestinal lining (Wikipedia, 2024).

Other names

DNA replication machineryNucleotide biosynthetic pathwayDe novo nucleotide synthesisDNA synthesis pathway

Drugs targeting this pathway primarily act as antimetabolites that inhibit rate-limiting enzymes in nucleotide biosynthesis (e.g., thymidylate synthase, dihydrofolate reductase) or as nucleoside analogs that are incorporated into DNA, leading to chain termination, DNA damage, and S-phase cell cycle arrest (StatPearls, 2023; PubMed, 2021).