Target type: molecularfunction
Catalysis of the reaction: adenosine + H2O = inosine + NH3. [EC:3.5.4.4]
Adenosine deaminase (ADA) activity is a crucial enzymatic process involved in the purine nucleotide metabolism pathway. It catalyzes the hydrolytic deamination of adenosine to inosine, a reaction that converts the adenine base to hypoxanthine. This conversion is essential for maintaining proper purine nucleotide homeostasis and preventing the accumulation of deoxyadenosine, which can be toxic to cells.
ADA functions by binding adenosine to its active site. The enzyme then utilizes a water molecule to hydrolyze the amino group at the 6-position of the adenine ring, releasing ammonia and forming inosine. The reaction requires a divalent metal ion, typically zinc, for optimal activity.
The molecular function of ADA activity is significant for several reasons:
* **Purine nucleotide balance:** ADA activity maintains a delicate balance of purine nucleotides, ensuring the availability of essential building blocks for DNA, RNA, and other cellular processes.
* **Deoxyadenosine detoxification:** ADA's deamination of deoxyadenosine prevents the accumulation of this toxic metabolite, which can inhibit DNA synthesis and cause severe immune dysfunction.
* **Immune function:** ADA activity is particularly critical for the development and function of the immune system. Deficiency in ADA activity leads to severe combined immunodeficiency (SCID), a life-threatening disorder characterized by impaired T-cell and B-cell development.
* **Other cellular processes:** ADA activity may also play a role in other cellular processes, including cell growth, differentiation, and apoptosis.
In summary, ADA activity is a vital enzymatic function with essential roles in purine nucleotide metabolism, deoxyadenosine detoxification, and immune system development. Its molecular function involves the hydrolytic deamination of adenosine to inosine, a critical step in maintaining cellular homeostasis and preventing toxic metabolite accumulation.'
"
| Protein | Definition | Taxonomy |
|---|---|---|
| Adenosine deaminase | An adenosine deaminase that is encoded in the genome of cow. [OMA:P56658, PRO:DNx] | Bos taurus (cattle) |
| Adenosine deaminase-like protein | An adenosine deaminase-like protein that is encoded in the genome of human. [PRO:DNx, UniProtKB:Q6DHV7] | Homo sapiens (human) |
| Adenosine deaminase | An adenosine deaminase that is encoded in the genome of human. [PRO:DNx, UniProtKB:P00813] | Homo sapiens (human) |
| Compound | Definition | Classes | Roles |
|---|---|---|---|
| 9-(2-hydroxy-3-nonyl)adenine | 9-(2-hydroxy-3-nonyl)adenine: specific inhibitor of adenosine deaminase | ||
| adenosine monophosphate | Adenosine Monophosphate: Adenine nucleotide containing one phosphate group esterified to the sugar moiety in the 2'-, 3'-, or 5'-position. | adenosine 5'-phosphate; purine ribonucleoside 5'-monophosphate | adenosine A1 receptor agonist; cofactor; EC 3.1.3.1 (alkaline phosphatase) inhibitor; EC 3.1.3.11 (fructose-bisphosphatase) inhibitor; fundamental metabolite; micronutrient; nutraceutical |
| benzil | benzil : 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-chloroadenosine | 5-chloroformycin A: structure given in first source | purine nucleoside | |
| 2-fluoroadenosine | adenosines; organofluorine compound | ||
| 2'-deoxyadenosine | 2'-deoxyformycin A: RN not in Chemline 9/85; RN and structure given in first source | purine 2'-deoxyribonucleoside; purines 2'-deoxy-D-ribonucleoside | Escherichia coli metabolite; human metabolite; mouse metabolite; Saccharomyces cerevisiae metabolite |
| dideoxyadenosine | Dideoxyadenosine: 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 |
| vidarabine | adenine 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-deazaadenosine | 3-deazaadenosine: RN given refers to parent cpd. | ||
| coformycin | coformycins | EC 3.5.4.4 (adenosine deaminase) inhibitor | |
| adefovir | adefovir : 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 |
| adenosine | quinquefolan B: isolated from roots of Panax quinquefolium L.; RN not in Chemline 10/87; RN from Toxlit | adenosines; purines D-ribonucleoside | analgesic; anti-arrhythmia drug; fundamental metabolite; human metabolite; vasodilator agent |
| 2'3'-didehydro-2'3'-dideoxyadenosine | 2'3'-didehydro-2'3'-dideoxyadenosine: structure given in first source | ||
| nebularine | nebularine : 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-aminoadenosine | purine nucleoside | ||
| 2,6-diamino-9-(2-hydroxyethoxymethyl)purine | 2,6-diamino-9-(2-hydroxyethoxymethyl)purine: adenosine deaminase converts above cpd to acylovir | ||
| 8-azaadenosine | N-glycosyl compound | ||
| 8-aminoadenosine | |||
| 6-methoxypurine arabinoside | |||
| o(6)-methyldeoxyguanylic acid | O(6)-methyldeoxyguanylic acid: incorporated into DNA by DNA polymerase I & II | ||
| 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. | EHNA | EC 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-deazaadenosine | 1-deazaadenosine: inhibits nucleic acid & protein synthesis; structure given in first source | ||
| pentostatin | pentostatin : 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. | coformycins | antimetabolite; antineoplastic agent; Aspergillus metabolite; bacterial metabolite; EC 3.5.4.4 (adenosine deaminase) inhibitor |
| formycin | formycin | antineoplastic agent | |
| 1-deaza-2-chloro-n(6)-cyclopentyladenosine | 1-deaza-2-chloro-N(6)-cyclopentyladenosine: adenosine A(1) receptor agonist | ||
| fludarabine | purine nucleoside | ||
| 8-azanebularine | 8-azanebularine: structure in first source | ||
| msh, 4-nle-7-phe-alpha- | polypeptide | dermatologic drug | |
| deoxyinosine | purine 2'-deoxyribonucleoside; purines 2'-deoxy-D-ribonucleoside | Escherichia coli metabolite; human metabolite; mouse metabolite; plant metabolite; Saccharomyces cerevisiae metabolite | |
| inosine | inosines; purines D-ribonucleoside | Escherichia coli metabolite; human metabolite; mouse metabolite; Saccharomyces cerevisiae metabolite | |
| adenallene | adenallene: structure given in first source; inhibits replication and cytopathic effects of HIV in vitro |