purine-containing compound salvage

Definition

Target type: biologicalprocess

Any process that generates a purine-containing compound, any nucleobase, nucleoside, nucleotide or nucleic acid that contains a purine base, from derivatives of them without de novo synthesis. [GOC:jl]

Purine salvage pathways are critical for maintaining cellular purine nucleotide pools, which are essential for DNA and RNA synthesis, as well as other crucial cellular processes. These pathways allow cells to recycle pre-existing purine bases, such as adenine, guanine, and hypoxanthine, derived from the breakdown of nucleic acids or dietary sources, rather than synthesizing them de novo. This process saves energy and resources for the cell.

The salvage pathway begins with the uptake of purine bases from the extracellular environment or from the breakdown of cellular components. These bases are then converted into their respective nucleoside monophosphates (NMPs) by specific enzymes.

1. **Adenine** is salvaged by adenine phosphoribosyltransferase (APRT), which catalyzes the reaction of adenine with phosphoribosyl pyrophosphate (PRPP) to form AMP.

2. **Guanine** is salvaged by hypoxanthine-guanine phosphoribosyltransferase (HGPRT), which catalyzes the reaction of guanine with PRPP to form GMP.

3. **Hypoxanthine** is also salvaged by HGPRT, resulting in the formation of inosine monophosphate (IMP), which can be further converted to AMP or GMP.

These NMPs can then be further phosphorylated to nucleoside diphosphates (NDPs) and triphosphates (NTPs), which are the building blocks of DNA and RNA.

The purine salvage pathway plays a crucial role in maintaining cellular homeostasis, ensuring adequate supply of purine nucleotides for various metabolic processes. Defects in these pathways can lead to severe genetic disorders, such as Lesch-Nyhan syndrome, which results from a deficiency in HGPRT activity, causing a buildup of uric acid and neurological abnormalities.'
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Proteins (3)

Compounds (32)