In biochemistry, nucleotides—composed of a pentose sugar, a nitrogenous base (purine or pyrimidine), and one or more phosphates—are synthesized by cells via two distinct strategies: de novo synthesis from simple precursors (amino acids, one-carbon donors, and carbon dioxide) or salvage synthesis from degraded nucleotide fragments. Purine and pyrimidine synthesis proceed by separate pathways with different ring-assembly strategies (purines assemble their ring directly on the ribose sugar, while pyrimidines assemble the ring first and attach it to the sugar afterward), and both pathways are tightly regulated to maintain the proper balance of nucleotide pools, since imbalance increases the risk of mutation.
In biochemistry, nucleotides—composed of a pentose sugar, a nitrogenous base (purine or pyrimidine), and one or more phosphates—are synthesized by cells via two distinct strategies: de novo synthesis…