Page last updated: 2024-10-24

purine ribonucleoside monophosphate biosynthetic process

Definition

Target type: biologicalprocess

The chemical reactions and pathways resulting in the formation of purine ribonucleoside monophosphate, a compound consisting of a purine base linked to a ribose sugar esterified with phosphate on the sugar. [GOC:go_curators, ISBN:0198506732]

Purine ribonucleoside monophosphate biosynthesis, also known as de novo purine nucleotide biosynthesis, is a complex metabolic pathway that produces the purine nucleotides, adenine monophosphate (AMP) and guanine monophosphate (GMP), which are essential building blocks for DNA, RNA, and other vital biomolecules. This process occurs in the cytoplasm of cells and involves a series of enzymatic reactions that use simple precursor molecules, such as amino acids, carbon dioxide, and tetrahydrofolate, to build the purine ring structure.

The pathway can be broadly divided into two stages:

1. **Formation of the purine ring:** This initial stage involves a series of 10 enzymatic reactions that assemble the purine ring structure. It starts with the formation of phosphoribosyl pyrophosphate (PRPP) from ribose-5-phosphate, which acts as a precursor molecule for the purine ring. The subsequent steps involve the sequential addition of various precursor molecules, such as glycine, glutamine, aspartate, formate, and tetrahydrofolate, to the growing purine ring. The final product of this stage is inosine monophosphate (IMP), which is the first purine nucleotide formed.

2. **Conversion of IMP to AMP and GMP:** The second stage involves the conversion of IMP into AMP and GMP. IMP is converted to AMP by the enzyme adenylate kinase, which uses adenosine triphosphate (ATP) as a phosphate donor. GMP is synthesized from IMP through a two-step process. First, IMP is oxidized to xanthosine monophosphate (XMP) by IMP dehydrogenase. Then, XMP is converted to GMP by the enzyme GMP synthetase, which utilizes glutamine as a source of nitrogen.

The purine ribonucleoside monophosphate biosynthetic process is highly regulated to ensure that the appropriate levels of purine nucleotides are maintained in the cell. This regulation occurs at several levels, including the availability of precursor molecules, the activity of enzymes involved in the pathway, and the feedback inhibition by purine nucleotides.

In summary, purine ribonucleoside monophosphate biosynthesis is a fundamental metabolic pathway that plays a vital role in cell function. It provides the building blocks for DNA, RNA, and other essential molecules, and it is tightly regulated to ensure that the cell maintains the appropriate balance of purine nucleotides.'
"

Proteins (5)

ProteinDefinitionTaxonomy
Adenosine deaminase An adenosine deaminase that is encoded in the genome of cow. [OMA:P56658, PRO:DNx]Bos taurus (cattle)
GMP synthase [glutamine-hydrolyzing] A GMP synthase [glutamine-hydrolyzing] that is encoded in the genome of human. [PRO:DNx, UniProtKB:P49915]Homo sapiens (human)
Trifunctional purine biosynthetic protein adenosine-3A trifunctional purine biosynthetic protein adenosine-3 that is encoded in the genome of human. [PRO:DNx, UniProtKB:P22102]Homo sapiens (human)
GMP synthase [glutamine-hydrolyzing] A GMP synthase [glutamine-hydrolyzing] that is encoded in the genome of human. [PRO:DNx, UniProtKB:P49915]Homo sapiens (human)
Trifunctional purine biosynthetic protein adenosine-3A trifunctional purine biosynthetic protein adenosine-3 that is encoded in the genome of human. [PRO:DNx, UniProtKB:P22102]Homo sapiens (human)

Compounds (34)

CompoundDefinitionClassesRoles
benzilbenzil : An alpha-diketone that is ethane-1,2-dione substituted by phenyl groups at positions 1 and 2 respectively.

benzil: structure
alpha-diketone;
aromatic ketone
2-chloroadenosine5-chloroformycin A: structure given in first sourcepurine nucleoside
2-fluoroadenosineadenosines;
organofluorine compound
2'-deoxyadenosine2'-deoxyformycin A: RN not in Chemline 9/85; RN and structure given in first sourcepurine 2'-deoxyribonucleoside;
purines 2'-deoxy-D-ribonucleoside
Escherichia coli metabolite;
human metabolite;
mouse metabolite;
Saccharomyces cerevisiae metabolite
dideoxyadenosineDideoxyadenosine: A dideoxynucleoside compound in which the 3'-hydroxy group on the sugar moiety has been replaced by a hydrogen. This modification prevents the formation of phosphodiester linkages which are needed for the completion of nucleic acid chains. The compound is an inhibitor of HIV replication, acting as a chain-terminator of viral DNA by binding to reverse transcriptase. Its principal side effect is nephrotoxicity. In vivo, dideoxyadenosine is rapidly metabolized to DIDANOSINE (ddI) by enzymatic deamination; ddI is then converted to dideoxyinosine monophosphate and ultimately to dideoxyadenosine triphosphate, the putative active metabolite.adenosines;
purine 2',3'-dideoxyribonucleoside
EC 3.5.4.4 (adenosine deaminase) inhibitor;
EC 4.6.1.1 (adenylate cyclase) inhibitor
vidarabineadenine arabinoside : A purine nucleoside in which adenine is attached to arabinofuranose via a beta-N(9)-glycosidic bond.beta-D-arabinoside;
purine nucleoside
antineoplastic agent;
bacterial metabolite;
nucleoside antibiotic
3-deazaadenosine3-deazaadenosine: RN given refers to parent cpd.
coformycincoformycinsEC 3.5.4.4 (adenosine deaminase) inhibitor
adefoviradefovir : A member of the class of phosphonic acids that is methylphosphonic acid in which one of the methyl hydrogens has been replaced by a 2-(6-amino-9H-purin-9-yl)ethoxy group. An inhibitor of HIV-1 reverse transcriptase, the bis(t-butoxycarbonyloxymethyl) ester (dipivoxil ester) prodrug is used to treat chronic hepatitis B viral infection.

adefovir: inhibitor of African swine fever virus

adefovir(1-) : A organophosphonate oxoanion obtained by removal of a proton from the phosphonate group of adefovir, a nucleoside reverse transcriptase inhibitor. It is the major microspecies at pH 7.3 (according to Marvin v 6.2.0.).
6-aminopurines;
ether;
phosphonic acids
antiviral drug;
DNA synthesis inhibitor;
drug metabolite;
HIV-1 reverse transcriptase inhibitor;
nephrotoxic agent
adenosinequinquefolan B: isolated from roots of Panax quinquefolium L.; RN not in Chemline 10/87; RN from Toxlitadenosines;
purines D-ribonucleoside
analgesic;
anti-arrhythmia drug;
fundamental metabolite;
human metabolite;
vasodilator agent
2'3'-didehydro-2'3'-dideoxyadenosine2'3'-didehydro-2'3'-dideoxyadenosine: structure given in first source
psicofuraninepsicose derivative;
purine nucleoside
nebularinenebularine : A purine ribonucleoside that is 9H-purine attached to a beta-D-ribofuranosyl residue at position 9 via a glycosidic (N-glycosyl) linkage.

nebularine: structure
purine ribonucleoside;
purines D-ribonucleoside
fungal metabolite
2-aminoadenosinepurine nucleoside
2,6-diamino-9-(2-hydroxyethoxymethyl)purine2,6-diamino-9-(2-hydroxyethoxymethyl)purine: adenosine deaminase converts above cpd to acylovir
8-azaadenosineN-glycosyl compound
8-aminoadenosine
angustmycin aangustmycin A: structure; from Streptomyces hygroscopicus; inhibits GMP synthesis6-aminopurines
6-methoxypurine arabinoside
methotrexatedicarboxylic acid;
monocarboxylic acid amide;
pteridines
abortifacient;
antimetabolite;
antineoplastic agent;
antirheumatic drug;
dermatologic drug;
DNA synthesis inhibitor;
EC 1.5.1.3 (dihydrofolate reductase) inhibitor;
immunosuppressive agent
9-(2-hydroxy-3-nonyl)adenine(2R,3S)-EHNA : EHNA of absolute configuration 2R,3S. Selective inhibitor of cGMP-stimulated phosphodiesterase (PDE2) (IC50 = 0.8 - 4 mM). Also a potent inhibitor of adenosine deaminase.EHNAEC 3.1.4.* (phosphoric diester hydrolase) inhibitor;
EC 3.5.4.4 (adenosine deaminase) inhibitor
9-(2-hydroxy-3-nonyl)adenine(2S,3R)-EHNA : EHNA of absolute configuration 2S,3R.EHNA
1-deazaadenosine1-deazaadenosine: inhibits nucleic acid & protein synthesis; structure given in first source
pentostatinpentostatin : A member of the class of coformycins that is coformycin in which the hydroxy group at position 2' is replaced with a hydrogen. It is a drug used for the treatment of hairy cell leukaemia.

Pentostatin: A potent inhibitor of ADENOSINE DEAMINASE. The drug induces APOPTOSIS of LYMPHOCYTES, and is used in the treatment of many lymphoproliferative malignancies, particularly HAIRY CELL LEUKEMIA. It is also synergistic with some other antineoplastic agents and has immunosuppressive activity.
coformycinsantimetabolite;
antineoplastic agent;
Aspergillus metabolite;
bacterial metabolite;
EC 3.5.4.4 (adenosine deaminase) inhibitor
formycinformycinantineoplastic agent
1-deaza-2-chloro-n(6)-cyclopentyladenosine1-deaza-2-chloro-N(6)-cyclopentyladenosine: adenosine A(1) receptor agonist
fludarabinepurine nucleoside
8-azanebularine8-azanebularine: structure in first source
deoxyinosinepurine 2'-deoxyribonucleoside;
purines 2'-deoxy-D-ribonucleoside
Escherichia coli metabolite;
human metabolite;
mouse metabolite;
plant metabolite;
Saccharomyces cerevisiae metabolite
inosineinosines;
purines D-ribonucleoside
Escherichia coli metabolite;
human metabolite;
mouse metabolite;
Saccharomyces cerevisiae metabolite
5,11-methenyltetrahydrohomofolate
pemetrexedpemetrexed disodium : An organic sodium salt that is the disodium salt of N-{4-[2-(2-amino-4-oxo-4,7-dihydro-1H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl]benzoyl}-L-glutamic acid. Inhibits thymidylate synthase (TS), 421 dihydrofolate reductase (DHFR), and glycinamide ribonucleotide formyltransferase (GARFT).N-acyl-L-glutamic acid;
pyrrolopyrimidine
antimetabolite;
antineoplastic agent;
EC 1.5.1.3 (dihydrofolate reductase) inhibitor;
EC 2.1.1.45 (thymidylate synthase) inhibitor;
EC 2.1.2.2 (phosphoribosylglycinamide formyltransferase) inhibitor
lometrexollometrexol: RN & structure given in first source;
adenalleneadenallene: structure given in first source; inhibits replication and cytopathic effects of HIV in vitro