AboutBlogDownloadExploreHelpGet Data

Pathway: superpathway of purine biosynthesis and salvage pathways

Biochemical pathways in S. cerevisiae are manually curated and maintained in the YeastPathways database. This page summarizes the genes, enzymes, and metabolites involved in the pathway, along with the curated literature.

Pathway Name
superpathway of purine biosynthesis and salvage pathways
Pathway ID
PWY3O-285
SGD ID
SGD:S000249719
Genes
AAH1 | ADE1 | ADE12 | ADE13 | ADE16 | ADE17 | ADE2 | ADE4 | ADE6 | ADE8 | ADK1 | ADK2 | ADO1 | AMD1 | APT1 | APT2 | GUA1 | GUD1 | GUK1 | HPT1 | IMD2 | IMD3 | IMD4 | ISN1 | PNP1 | RNR1 | RNR2 | RNR3 | RNR4 | TRX1 | TRX2 | TRX3 | XPT1 | YNK1
Chemical Compounds
2-formamido-N(1)-(5-phospho-D-ribosyl)acetamidine | 5'-xanthylate(2-) | 5-O-phosphonato-alpha-D-ribofuranosyl diphosphate(5-) | 5-amino-1-(5-phospho-D-ribosyl)imidazole-4-carboxamide(2-) | 5-amino-1-(5-phosphonato-D-ribosyl)imidazole-4-carboxylate | 5-amino-1-(5-phosphonato-beta-D-ribosyl)imidazol-3-ium | 5-formamido-1-(5-phospho-D-ribosyl)imidazole-4-carboxamide(2-) | 5-phospho-beta-D-ribosylaminium(1-) | 9H-xanthine | ADP(3-) | ATP(4-) | GDP(3-) | GTP(4-) | IMP(2-) | L-aspartate(1-) | L-glutamate(1-) | L-glutamine zwitterion | N(1)-(5-phospho-D-ribosyl)glycinamide(1-) | N(2)-formyl-N(1)-(5-phospho-D-ribosyl)glycinamide(2-) | N(6)-(1,2-dicarboxylatoethyl)-AMP(4-) | NAD(1-) | NADH(2-) | SAICAR(4-) | adenine | adenosine | adenosine 5'-monophosphate(2-) | alpha-D-ribose 1-phosphate(2-) | ammonium | carbon dioxide | dADP(3-) | dATP(4-) | dGDP(3-) | dGTP(4-) | diphosphoric acid | formate | fumarate(2-) | glycine zwitterion | guanine | guanosine 5'-monophosphate(2-) | hydrogenphosphate | hydron | hypoxanthine | inosine | water

Pathway Diagram

Diagram of the pathway from YeastPathways. Click "View interactive diagram at YeastPathways" for the zoomable, clickable version.

superpathway of purine biosynthesis and salvage pathways pathway diagram

View interactive diagram at YeastPathways

Pathway Summary

Purine and pyrimidine nucleotides serve many diverse and essential roles in the cell. They are precursors to DNA, RNA, and many important metabolites (e.g. CDP-diacylglycerol). In addition, nucleotides can be used as an energy source (primarily as ATP), signaling molecules, and cofactor components (e.g. coenzyme A). In yeast and most eukaryotes, purine nucleotides levels are maintained via a combination of de novo synthesis and salvage pathways. The salvage pathways utilize purine bases and nucleosides taken up from the environment or formed from metabolism to synthesize purine nucleoside monophosphates. Compared to the de novo pathway, where 5-phosphoribosyl-1-pyrophosphate (PRPP) is converted to the adenylicguanylic nucleotide precursor inosine 5-monophosphate (IMP) over many ATP-consuming steps, the salvage pathways synthesize IMP, GMP, and AMP directly from PRPP and a purine base via the action of purine phosphoribosyltransferases. When purines are abundant in the growth medium, the salvage pathways are the preferred routes of purine nucleotide synthesis. In S. cerevisiae, most of the ADE genes responsible for de novo synthesis of IMP and AMP are repressed in response to extracellular adenine, whereas extracellular guanine strongly represses the IMD genes responsible for the rate-limiting step of GMP synthesis. Adenine limitation, on the other hand, results in derepression of ADE genes and active de novo purine biosynthesis. Adenine-repressible transcriptional activation of ADE genes is mediated by the transcription factors Bas1p and Pho2p.

Genes Involved

Genes whose products participate in this pathway, with their systematic names, EC numbers (where the gene product is an enzyme with an assigned EC number), and the gene's SGD description.

GeneSystematic NameEC NumberDescription
AAH1 YNL141W 3.5.4.2 Adenine deaminase (adenine aminohydrolase)
ADE1 YAR015W 6.3.2.6 N-succinyl-5-aminoimidazole-4-carboxamide ribotide synthetase
ADE12 YNL220W 6.3.4.4 Adenylosuccinate synthase
ADE13 YLR359W 4.3.2.2 Adenylosuccinate lyase
ADE16 YLR028C 2.1.2.3, 3.5.4.10 Enzyme of 'de novo' purine biosynthesis
ADE17 YMR120C 2.1.2.3, 3.5.4.10 Enzyme of 'de novo' purine biosynthesis
ADE2 YOR128C 4.1.1.21 Phosphoribosylaminoimidazole carboxylase
ADE4 YMR300C 2.4.2.14 Phosphoribosylpyrophosphate amidotransferase (PRPPAT)
ADE6 YGR061C 6.3.5.3 Formylglycinamidine-ribonucleotide (FGAM)-synthetase
ADE8 YDR408C 2.1.2.2 Phosphoribosyl-glycinamide transformylase
ADK1 YDR226W 2.7.4.3 Adenylate kinase, required for purine metabolism
ADK2 YER170W 2.7.4.10 Mitochondrial adenylate kinase
ADO1 YJR105W 2.7.1.20 Adenosine kinase
AMD1 YML035C 3.5.4.6 AMP deaminase
APT1 YML022W 2.4.2.7 Adenine phosphoribosyltransferase
APT2 YDR441C 2.4.2.7 Potential adenine phosphoribosyltransferase
GUA1 YMR217W 6.3.5.2 GMP synthase
GUD1 YDL238C 3.5.4.3 Guanine deaminase
GUK1 YDR454C 2.7.4.8 Guanylate kinase
HPT1 YDR399W 2.4.2.8 Dimeric hypoxanthine-guanine phosphoribosyltransferase
IMD2 YHR216W 1.1.1.205 Inosine monophosphate dehydrogenase
IMD3 YLR432W 1.1.1.205 Inosine monophosphate dehydrogenase
IMD4 YML056C 1.1.1.205 Inosine monophosphate dehydrogenase
ISN1 YOR155C 3.1.3.99 Inosine 5'-monophosphate (IMP)-specific 5'-nucleotidase
PNP1 YLR209C 2.4.2.1 Purine nucleoside phosphorylase
RNR1 YER070W 1.17.4.1 Major isoform of large subunit of ribonucleotide-diphosphate reductase
RNR2 YJL026W 1.17.4.1 Ribonucleotide-diphosphate reductase (RNR), small subunit
RNR3 YIL066C 1.17.4.1 Minor isoform of large subunit of ribonucleotide-diphosphate reductase
RNR4 YGR180C 1.17.4.1 Ribonucleotide-diphosphate reductase (RNR) small subunit
TRX1 YLR043C Cytoplasmic thioredoxin isoenzyme
TRX2 YGR209C Cytoplasmic thioredoxin isoenzyme
TRX3 YCR083W Mitochondrial thioredoxin
XPT1 YJR133W Xanthine-guanine phosphoribosyl transferase
YNK1 YKL067W 2.7.4.6 Nucleoside diphosphate kinase

Functional Networks

Functional Networks show how the genes in this pathway work together: a graph linking the pathway to its genes and their shared GO biological-process terms and phenotype observables, and the GO-CAM causal activity models that involve these genes.

Shared Annotations

Loading network…

GO-CAMs

GO-CAM (Gene Ontology Causal Activity Model) pathway models that involve the genes in this pathway. A gene can participate in more than one model, so use the dropdown to switch between them; the model for this pathway is shown by default.

Loading GO-CAMs…

GO Enrichment

Gene Ontology biological-process terms enriched among the genes in this pathway, computed with GO Term Finder. Terms are shown with the number of pathway genes annotated to them and the corrected p-value.

Loading GO enrichment…

References

List of references used specifically to curate the information on this page.

Resources

YeastPathways