Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.4.2.7 (adenine phosphoribosyltransferase)
 692 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The thermostability of erythrocyte hypoxanthine guanine phosphoribosyltransferase of 2 Werner's syndrome patients was compared with that of normal subjects of different ages. No significant difference was observed regarding the thermal stability of the enzyme among normal subjects and Werner's syndrome patients. The activities of other erythrocyte enzymes, phosphoribosylpyrophosphate synthetase, adenine phosphoribosyltransferase, adenosine deaminase and purine nucleoside phosphorylase, were similar between Werner's syndrome and normal subjects.
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PMID:Normal thermostability of hypoxanthine guanine phosphoribosyltransferase in erythrocytes from Werner's syndrome patients. 377 Apr 88

African trypanosomes can convert adenosine to adenosine monophosphate. However, in Trypanosoma brucei, as in T. vivax and T. congolense, most of the adenosine is broken down to adenine before conversion to the nucleotide by adenine phosphoribosyltransferase. Trypanosoma brucei and T. vivax use the purine nucleoside hydrolase for adenosine cleavage while T. congolense uses purine nucleoside phosphorylase for the nucleoside cleavage. Trypanosoma vivax also deaminates adenine to hypoxanthine before its conversion to adenosine monophosphate by way of inosine monophosphate. All African trypanosomes lack adenosine deaminase. This finding particularly demonstrates that the effectiveness of the therapy of African trypanosomiasis with adenosine analogue drugs will depend upon the strain of trypanosome which causes the infection.
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PMID:Adenosine cycle in African trypanosomes. 392 Sep 82

1. Both the acid-soluble fraction and the nucleic acid fraction of wheat embryos were extensively labelled after incubation for 6hr. in the presence of [8-(14)C]adenine. Subsequent incubation in the absence of labelled adenine resulted in no loss of radioactivity to the medium during a 48hr. period. Radioautography indicated that during this period there was a continuous increase in the radioactivity present in the acid-insoluble fractions of the root and leaf tissues relative to that present in the coleorhiza and coleoptile. 2. During incubation at 25 degrees there was a 26-fold increase in the activity of 3'-nucleotidase between 4hr. and 24hr.; the activities of enzymes hydrolysing AMP and IMP increased to a smaller extent. The activities of adenine phosphoribosyltransferase and hypoxanthine phosphoribosyltransferase increased three- to five-fold during incubation at 25 degrees for 24hr. 3. Adenosine kinase, inosine phosphorylase and 5-phosphoribosyl pyrophosphate synthetase activities were high in extracts from dry embryos and did not increase during 48hr. at 25 degrees . 4. The increase in 3'-nucleotidase activity was prevented by cycloheximide, cryptopleurine or incubation at 4 degrees , but not by actinomycin D; these treatments did not depress the activity of the other enzymes measured. 5. The results are discussed in relation to RNA translocation within the wheat embryo during germination.
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PMID:Purine metabolism in germinating wheat embryos. 431 15

1. Japanese sumo wrestlers have a diet rich in energy, which results in marked obesity. Their plasma urate and triglyceride levels were significantly elevated. 2. Erythrocyte phosphoribosylpyrophosphate (PRPP) and ATP concentrations in sumo wrestlers were significantly elevated when compared to the levels in control subjects. 3. There were no significant differences in erythrocyte PRPP synthetase (EC 2.7.6.1), purine nucleoside phosphorylase (EC 2.4.2.1) and hypoxanthine guanine phosphoribosyl transferase (EC 2.4.2.8) activities between sumo wrestlers and control subjects. 4. Erythrocyte adenosine kinase (EC 2.7.1.20), adenosine deaminase (EC 3.5.4.4) and adenine phosphoribosyl transferase (EC 2.4.2.7) activities in sumo wrestlers were significantly elevated. 5. It seems that sumo wrestlers have an increased turnover of adenine nucleotides which may contribute to hyperuricaemia.
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PMID:Elevated erythrocyte phosphoribosylpyrophosphate and ATP concentrations in Japanese sumo wrestlers. 618 38

A methodology is presented for systemic analysis of purine enzymes in small lymphocyte subfractions. For the determination of 7 different enzymes of purine metabolism *hypoxanthine-guanine phosphoribosyltransferase (HG-PRT), adenine phosphoribosyltransferase (A-PRT), adenosine deaminase (ADA), purine nucleoside phosphorylase (PNP), adenosine kinase (AK), 5'-nucleotidase (5'N), and AMP-deaminase) less than 200,000 peripheral blood lymphocytes are needed. 1000-6000 lyophilised lymphocytes are incubated in micro-incubation vessels (3 microliter) with radioactive substrates for 15-180 min. Separation of substrates and products is achieved by thin-layer chromatography on PEI-cellulose. Addition of BSA to the incubation mixtures results in higher specific enzyme activities and narrower ranges of mean values of a control group.
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PMID:Enzymes of purine nucleotide metabolism in human lymphocytes. 625 89

We have studied purine metabolism in mononuclear and polymorphonuclear cells from uraemic patients using microradiochemical enzyme assays and high-pressure liquid chromatography. In mononuclear cell lysates the mean activities of adenosine deaminase (EC 3.5.4.4) and 5'-nucleotidase (EC 3.1.3.5) were significantly diminished. The activities of adenylate kinase (EC 2.7.4.3), purine nucleoside phosphorylase (EC 2.4.2.1), adenine phosphoribosyltransferase (EC 2.4.2.7), and hypoxanthine phosphoribosyltransferase (EC 2.4.2.8) were not significantly different in the two groups. The activities of adenosine deaminase and adenine phosphoribosyltransferase were reduced in the polymorphonuclear cell lysates. No clear differences emerged in the concentration of adenine nucleotides in the mononuclear cells. The significance of these changes, which are less marked than those in erythrocytes, is discussed with reference to the immunodeficiency associated with uraemia.
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PMID:Activities of enzymes involved in purine metabolism and some related adenine nucleotide concentrations of leucocytes in renal failure. 629 37

Adenosine deaminase (ADA), purine nucleoside phosphorylase (PNP), 5'nucleotidase (5'NT), ecto-5'NT, hypoxanthine-guanine phosphoribosyltransferase(HGPRT), adenine phosphoribosyltransferase(APRT), adenosine kinase(AK), AMP deaminase (AMPD) and adenylate kinase(AdKin) activities were assayed in leukemic cells from bone marrow and/or peripheral blood of 43 newly diagnosed children with acute lymphoblastic leukemia(ALL). These enzyme activities have been investigated in relation to some immunological markers. ADA activity was higher in E-rosette positive leukemia(E+ ALL), while HGPRT, APRT, PNP, 5'NT, ecto-5'NT and AdKin activities were found to be lower in E+ ALL as compared to E- ALL. In common ALL (cALL) antigen positive leukemia, mean ADA activity was significantly lower as compared to cALL- leukemia, whereas PNP, 5'NT, ecto-5'NT and AdKin activities were significantly higher. cALL cells with cytoplasmic immunoglobulin M(IgM) heavy chains were found to have mean 5'NT activities twice as high as cALL cells lacking cytoplasmic IgM heavy chains. In two patients who had surface immunoglobulins on their cell membranes, low 5'NT activities were found. When measuring enzyme activities after 2-4 days of prednisone monotherapy, only mean ADA and HGPRT activities decreased in non-B, non-T ALL. These decreases were not significant in T-ALL patients. Mean enzyme activities in the leukemic cells of five patients with relapse were comparable to those in newly diagnosed patients, except for 5'NT, which was found to be within the activity range of control peripheral blood lymphocytes. It is concluded that ADA and AdKin activities are suitable as markers for E+ ALL and cALL+ leukemias respectively. 5'NT might help to distinguish between cALL cells having and lacking pre-B characteristics. Since 5'NT activity may also be decreased in B-ALL, it is not suitable as a T-ALL marker. Enzymes of purine metabolism in leukemic relapse need further investigation.
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PMID:Purine metabolism in childhood acute lymphoblastic leukemia: biochemical markers for diagnosis and chemotherapy. 631 Feb 74

The activities of five clinically important enzymes of purine metabolism have been determined in lymphocytes from 62 patients with various types of solid tumors. The activity of purine nucleoside phosphorylase was increased in all patient groups studied, i.e. small cell bronchogenic carcinoma (n = 30), carcinoma of the breast (n = 17) and other tumors (n = 15), compared to cells form normal donors. Activities of adenosine deaminase, adenine phosphoribosyltransferase (APRT), hypoxanthine (guanine) phosphoribosyltransferase (HGPRT), and 5'-nucleotidase (5'-NUC) vary little from control values, except for lower levels of APRT in lymphocytes from patients with carcinoma of the breast. In patients with small cell bronchogenic carcinoma, enzyme levels were also determined in granulocytes, where increased APRT activity was found. Following cytostatic treatment of these patients, significant decreases were seen in lymphocytic HGPRT and 5'-NUC activities.
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PMID:Purine metabolizing enzymes in lymphocytes from patients with solid tumors. 632 Jun 1

Adenosine deaminase (ADA), 5'nucleotidase (5'NT), ecto-5'NT, purine nucleoside phosphorylase (PNP), hypoxanthine-guanine phosphoribosyltransferase (HGPRT), adenine phosphoribosyltransferase (APRT), adenosine kinase (AK), AMP-deaminase (AMPD) and adenylate kinase (AdKin) activities were assayed in peripheral blood lymphoid cells from 20 patients with B-cell type chronic lymphocytic leukemia (CLL). Significantly decreased mean activities of ADA, 5'NT, ecto-5'NT, PNP and AMPD were observed when comparing B-CLL lymphoid cells with control peripheral blood lymphocytes (PBL). AK and AdKin activities however, were found to be higher in B-CLL. Relatively wide ranges of ADA and 5'NT activity were observed. In patients with paraproteinaemia, 5'NT activity was found to be relatively high and in the range of the activities in normal PBL. ADA activity seemed to be slightly higher in patients without paraproteinaemia. No correlation could be found between the enzyme activities and the number of cells rosetting with sheep erythrocytes or bearing surface immunoglobulin (sIg). A relationship was suggested between 5'NT activity and Ig production.
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PMID:Enzymological studies in chronic lymphocytic leukemia. 640 72

We have isolated numerous mutants containing mutations in the salvage pathways of purine synthesis. The mutations cause deficiencies in adenine phosphoribosyltransferase (adeF), in hypoxanthine-guanine phosphoribosyltransferase (guaF), in adenine deaminase (adeC), in inosine-guanosine phosphorylase, (guaP), and in GMP reductase (guaC). The physiological properties of mutants containing one or more of these mutations and corresponding enzyme measurements have been used to derive a metabolic chart of the purine salvage pathway of Bacillus subtilis.
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PMID:Purine salvage pathways of Bacillus subtilis and effect of guanine on growth of GMP reductase mutants. 640 59


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