Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.5.4.17 (adenosine deaminase)
 5,206 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Treatment of the therapeutically important 9-beta-D-xylofuranosyladine in strongly alkaline medium with dimethyl sulphate led principally to etherification of sugar hydroxyls and, to a minor extent, to formation of products with a methylated exocyclic amino group. The various O'-methyl derivatives of xylofuranosyladenine were fractionated on a strongly basic ion exchange column, and isolated in pure form. Also isolated was 9-beta-D-xylofuranosyl-N6-methyladenine and its 2'-O-methyl derivative. The products were identified from their 1H NMR spectra, for which extensive data are tabulated. The susceptibilities of the various derivatives to calf intestinal adenosine deaminase were examined in relation to those of other adenine nucleosides; in particular, 5'-O-methylation led to total loss of substrate properties for the riboside, arabinoside and xyloside of adenine.
Acta Biochim Pol 1977
PMID:Preparation of O'-METHYL derivatives of 9-beta-D-xylofuranosyladenine. 93 May 13

1. Diazomethane treatment of formycin A in the presence or absence of SnCl2 as catalyst, was used for the preparation of the 2'-O-methyl, 3'-O-methyl, N1-methyl and N2-methyl derivatives. The four possible dimethylated derivatives, 2'(3")-O,N1(N2)-dimethylformycins, were obtained by controlled treatment of formycin with diazomethane in the presence of SnCl2, and subsequent column chromatography for product isolation. 2. All the foregoing products were characterized and identified by chromatography, ultraviolet absorption spectra, and proton magnetic resonance spectroscopy. Extensive u.v. spectral data, and spectrally determined pK values, for the various derivatives are presented. 3. N2-Methylformycin B was also prepared by enzymatic deamination of the parent N2-methylformycin A. 4. The sequence of elution of N1-methylformycin and N2-methylformycin on a strongly basic ion exchange column suggested that the latter is in the syn conformation. The susceptibility of N2-methylformycin to adenosine deaminase shows that this analogue may adopt the anti conformation on reaction with the enzyme. 5. The active species in the SnCl2-catalysed monomethylation of the 2'(3') cishydroxyls of ribonucleosides by diazomethane was shown to be an organo-tin product of the reaction of SnC2 with diazomethane. This product, not identified, contained no nitrogen or chlorine. 6. A simple column chromatographic procedure is described for the desalting of heterocyclic bases and their nucleosides with pK values for ring protonation down to about 0.
Acta Biochim Pol 1977
PMID:Preparation and properties of formycin analogues methylated on the pyrazolo ring nitrogens and/or the ribose cis-hydroxyls. 93 May 15

Adenosine deaminase (ADA) was partially purified 486- and 994-fold from rat liver mitochondria and cytosol, respectively. Relative molecular mass of the enzymes from both fractions was 34,000. Km for adenosine and 2'-deoxy-adenosine were 3.08 x 10(-5) M and 3.03 x 10(-5) M for mitochondrial ADA and 3.12 x 10(-5) M and 2.87 x 10(-5) M for cytosolic ADA. The enzyme from both subcellular fractions had the maximum activity at pH 7.5-8.0, and pI 5.2 and 4.2 for mitochondrial and cytosolic enzyme, respectively. The enzyme was inhibited by erythro-9-(2-hydroxy-3-nonyl)adenine and 2'-deoxycoformycin with Ki 4.4 x 10(-7) M and 3.2 x 10(-7) M for mitochondrial ADA and 4.9 x 10(-7) M 2.8 x 10(-7) M for cytosolic ADA. Among the natural nucleoside and deoxynucleotide derivatives tested, deoxy-GTP and UTP inhibited only cytosolic adenosine deaminase by 60% and 40%, respectively.
Acta Biochim Pol 1992
PMID:Adenosine deaminase: physical and chemical properties of partially purified mitochondrial and cytosol enzyme from rat liver. 144 46

The effect of aminophylline administered intravenously in dose 250 mg on plasma oxypurines (hypoxanthine and xanthine) concentration as well as on plasma adenosine deaminase activity and plasma AMP deaminase activity was studied in 17 patients with bronchial asthma or chronic cor pulmonale. Initial plasma oxypurines concentration was 47.5 +/- 10.4 mumol/l and one hour after aminophylline administration decreased significantly (p less than 0.001) to the value 40.3 +/- 8.8 mumol/l. Plasma adenosine deaminase activity increased significantly from 4.74 +/- 2.3 IU to 6.9 +/- 2.77 IU (p less than 0.01), while plasma AMP deaminase activity did not change. The above results suggest indirectly that intravenous administration of aminophylline decreases serum adenosine concentration in studied patients.
Pol Arch Med Wewn 1991 Apr
PMID:[The effect of aminophylline on plasma oxypurines in patients with bronchial asthma or cor pulmonale]. 188 28

The activity of adenosine deaminase was determined in the cerebrospinal fluid in children with acute lymphoblastic leukaemia in various phases. It was found that an evident rise of this activity occurred during leukaemic meningeal involvement as compared with the initial phase the disease or with the first complete remission. After an episode of recurrent cerebrospinal leukaemia the activity of the enzyme was also higher than during the first complete remission. Such high values as during meningeal leukaemia were not found in inflammatory cerebrospinal fluid which suggests that determinations of this enzyme could be useful for differentiation of leukaemic infiltrations in the central nervous system against lymphocytic meningitis.
Acta Haematol Pol
PMID:[Adenosine deaminase activity in the cerebrospinal fluid of children with acute lymphoblastic leukemia]. 263 33

Cell-free extracts of nitrate-grown Aspergillus terricola catalyze the hydrolytic deamination of adenosine to inosine at maximum rate at pH 6.5 and 50 degrees C. Incubation of the extracts at 60 degrees C for 30 minutes caused about 66.7% loss in activity. Results indicated the involvement of SH groups in the catalytic site of adenosine deaminase. Frequent freezing and thawing of the enzyme preparation for three days (3 times) resulted in about 47% loss in activity. The enzyme is also inhibited by EDTA indicating that adenosine deaminase is a metaloenzyme. MgCl2 and CoSO4 had a remarkable activating effect, whereas MnCl2 showed a slight inhibitory effect on enzyme activity. The apparent Km value was calculated for adenosine and found to be 6.66 x 10(-3) M, which indicates the greater affinity of adenosine deaminase for adenosine.
Acta Microbiol Pol 1994
PMID:Properties of adenosine deaminase in extracts of Asperigillus terricola. 774 Sep 80

Serum uric acid and oxypurines (hypoxanthine and xanthine) renal excretion of uric acid and oxypurines as well as plasma adenosine deaminase activity and AMP deaminase activity were studied in 18 patients with essential hypertension and in 17 healthy subjects. The aim of the study was to evaluate uric acid production rate in essential hypertension. Serum uric acid was significantly higher (7.04 +/- 2.03 mg% = 370.5 +/- 106 mumol/l; p < 0.01) in essential hypertension in comparison with control group (5.2 +/- 1.0 mg% = 275.0 +/- 51.9 mumol/l) and plasma oxypurines were increased insignificantly. Impairment of fractional excretion of uric acid (p < 0.05) was found in patients with essential hypertension. Plasma adenosine deaminase activity and plasma AMP deaminase activity did not differ in the studied groups. Increased production of uric acid does not contribute the incidence of hyperuricemia in essential hypertension. The results suggest that tubular defect of oxypurines excretion similar to that of uric acid exists in patients with essential hypertension.
Pol Arch Med Wewn 1993 Mar
PMID:[Value of oxypurines and uric acid in plasma, renal excretion of oxypurines and uric acid as well as plasma adenosine deaminase and AMP deaminase activity in patients with essential hypertension]. 832 72

Adenosine deaminase (ADA) activity was studied in red blood cells of patients suffering from multiple sclerosis treated with adrenocorticotropic hormone (ACTH). ADA activity in hemolysates was determined according to the method of Hopkinson and calculated as units per g of hemoglobin. Activity of adenosine deaminase in healthy subjects was 0.871 +/- 0.251 U/g Hb. In patients with multiple sclerosis, before treatment ADA activity was 0.765 +/- 0.131 U/g Hb and was about 15.2% lower than in the control group (p < 0.02). After treatment with ACTH, ADA activity increased to 1.005 +/- 0.211 U/g Hb (p < 0.001). We have suggested that increased activity of adenosine deaminase in red blood cells of patients suffering from multiple sclerosis after treatment with ACTH is caused by diminution of superoxide generation, and therefore its sparing effect on cell membrane and enzyme is connected with membranes.
Pol J Pharmacol
PMID:Activity of adenosine deaminase in red blood cells of patients suffering from multiple sclerosis treated with adrenocorticotropic hormone. 886 75

The studies on the metabolism and toxic mechanism of 2-chloro-2'-deoxyadenosine (2CdA, Cladribine), a new antileukemic drug, were reviewed. 2CdA, being a 2-halogenated, adenosine deaminase-resistant analogue of deoxyadenosine, is phosphorylated to the mono-, di, and triphosphate chlorodeoxy adenosine and the first step of phosphorylation is taken in the presence of enzymes, mainly kinase deoxycytidine (although in mitochondria it is phosphorylated by kinase deoxyguanosine). Triphosphate derivative of 2CdA is commonly considered to be the agent inducing cell apoptosis resulting from inhibition of ribonucleotide reductase, DNA polymerases and DNA repair. Recent studies on toxicity of 2CdA showed that the nucleoside possesses inhibitory activity against enzymes which are responsible for metabolism of deoxyadenosine, which suggests that the mechanism of toxicity by 2CdA includes a block in dAdo metabolic pathways which is very important for normal function of immune system cells. The agent under discussion and two other adenosine analogues (i.e. fludarabine and 2'-deoxycoformycin) which exhibit cytotoxicity against dividing and resting lymphocytes revolutionized the treatment of indolent lymphoid malignancies (i.e. chronic lymphocytic leukemia, non-Hodgkin's lymphoma, cutaneous T cell lymphoma and hairy cell leukemia). Particularly, in the treatment of hairy cell leukemia, 2-chloro-2'-deoxyadenosine demonstrated excellent efficacy, achieved after a single 7-day course, with an acceptable tolerability profile, suggesting that cladribine is likely to be more effective than other agents recommended in this disease. Preliminary clinical data, extremely encouraging in the case of 2CdA indicate that biomolecular mechanisms of the drug cytotoxicity is worth wide presentation.
Acta Pol Pharm
PMID:2-Chloro-2'-deoxyadenosine (2CdA) biochemical aspects of antileukemic efficacy. 941 93

The isoenzymes ADA1 and ADA2 of the enzyme adenosine deaminase (ADA 3.5.4.4) deaminate mainly two nucleotides: adenosine and 2'-deoxyadenosine, molecules with many effects on human cells. Thus, the ADA1 and ADA2 in human cells are of extreme importance. Biochemical and biological properties of the isoenzymes ADA1 and ADA2 as well as their usefulness in diagnostic of many diseases were described.
Pol Merkur Lekarski 1997 Dec
PMID:[Adenosine deaminase: isoenzymes ADA1 and ADA2]. 952 70


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