PRPPderived

PRPPderived refers to biomolecules that originate from phosphoribosyl pyrophosphate (PRPP) through transferase reactions that attach the ribose-5-phosphate moiety to a base or other substrate. In cellular metabolism, PRPP serves as a key ribose donor in nucleotide biosynthesis and salvage pathways, producing a variety of PRPP-derived products, most prominently nucleotides and related ribosylated metabolites.

The main PRPP-derived products are nucleotides formed by phosphoribosyltransferases. Purine salvage uses enzymes such as adenine phosphoribosyltransferase (APRT) and hypoxanthine-guanine phosphoribosyltransferase (HGPRT) to convert adenine to AMP and hypoxanthine or guanine to IMP or GMP, respectively. Pyrimidine salvage involves orotate phosphoribosyltransferase (OPRT) forming orotidine monophosphate (OMP) from orotate, or uracil phosphoribosyltransferase (UPRT) forming UMP from uracil; in some organisms thymine phosphoribosyltransferase (TPRT) can convert thymine to TMP. These reactions exemplify PRPP-derived nucleotides, which can be further processed to other nucleotides or backbones such as CMP, UTP, and GTP.

Biological significance and regulation are linked to the balance between de novo synthesis and salvage, with PRPP availability and enzyme activity tightly controlled to meet cellular demand for RNA and DNA precursors. Defects in PRPP-dependent salvage enzymes or in PRPP synthesis can contribute to metabolic disorders and influence disease states, including certain immune and neurological conditions. PRPP-derived pathways are present across bacteria, archaea, and eukaryotes, reflecting their fundamental role in nucleotide metabolism and energy conservation.

See also: phosphoribosyltransferases, PRPP, nucleotide salvage, nucleotide metabolism.