Salvage Pathway
Nucleotide salvage ( German Bergungsweg ) is generally the term used for metabolic pathways , the synthesis of a biomolecule accomplish from its breakdown products - a form of recycling . A salvage pathway is a form of biochemical recovery process . In particular, the salvage pathway means that for purine nucleotides .
Purine nucleotide salvage
| Parent |
| Nucleotide salvage recovery process |
| Subordinate |
| AMP salvage GMP salvage IMP salvage XMP salvage |
| Gene Ontology |
|---|
| QuickGO |
The salvage pathway is used in the cytoplasm for the formation of mononucleotides from the free purine bases adenine , guanine and hypoxanthine . In addition to the breakdown to uric acid , it represents the main metabolic pathway for free purines with 90% . Compared to the de novo biosynthesis of purine mononucleotides, it is significantly more energy-efficient.
Procedure
A ribose phosphate is transferred to phosphoribosyl pyrophosphate (PRPP) on a free purine base with elimination of pyrophosphate . This creates the corresponding nucleotide.
The catalyzing enzymes are allosterically activated by PRPP and inhibited by their products.
| Purine base | + PRPP = nucleotide | by means of enzyme |
|---|---|---|
| Adenine | Adenosine monophosphate (AMP) | Adenine phosphoribosyl transferase (APRT) |
| Guanine | Guanosine monophosphate (GMP) | Hypoxanthine Guanine Phosphoribosyltransferase (HGPRT) |
| Hypoxanthine | Inosine monophosphate (IMP) | Hypoxanthine Guanine Phosphoribosyltransferase (HGPRT) |
clinic
A defect in the salvage pathway can lead to hyperuricemia .
A genetic defect in HGPRT leads to Lesch-Nyhan syndrome .
Web links
Individual evidence
- ↑ Florian Horn et al., Human Biochemistry. 3. Edition. Thieme Verlag, Stuttgart 2005, ISBN 3-13-130883-4 .