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Stipković Babić M, Makuc D, Plavec J, Martinović T, Kraljević Pavelić S, Pavelić K, Snoeck R, Andrei G, Schols D, Wittine K, Mintas M. Novel halogenated 3-deazapurine, 7-deazapurine and alkylated 9-deazapurine derivatives of L-ascorbic or imino-L-ascorbic acid: Synthesis, antitumour and antiviral activity evaluations. Eur J Med Chem 2015; 102:288-302. [PMID: 26291038 PMCID: PMC7125971 DOI: 10.1016/j.ejmech.2015.08.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 06/19/2015] [Accepted: 08/02/2015] [Indexed: 11/05/2022]
Abstract
Keeping the potential synergy of biological activity of synthetic anomalous derivatives of deazapurines and l-ascorbic acid (l-AA) in mind, we have synthesized new 3-, 7- and 9-deazapurine derivatives of l-ascorbic (1-4, 8-10, 13-15) and imino-l-ascorbic acid (5-7, 11, 12, 16-19). These novel compounds were evaluated for their cytostatic and antiviral activity in vitro against a panel of human malignant tumour cell lines and normal murine fibroblasts (3T3). Among all evaluated compounds, the 9-deazapurine derivative of l-AA (13) exerted the most potent inhibitory activity on the growth of CEM/0 cells (IC50 = 4.1 ± 1.8 μM) and strong antiproliferative effect against L1210/0 (IC50 = 4.7 ± 0.1 μM) while the 9-deazahypoxanthine derivative of l-AA (15) showed the best effect against HeLa cells (IC50 = 5.6 ± 1.3 μM) and prominent effect on L1210/0 (IC50 = 4.5 ± 0.5 μM). Furthermore, the 9-deazapurine derivative disubstituted with two imino-l-AA moieties (18) showed the best activity against L1210/0 tumour cells (IC50 = 4.4 ± 0.3 μM) and the most pronounced antiproliferative effects against MiaPaCa-2 cells (IC50 = 5.7 ± 0.2 μM). All these compounds showed selective cytostatic effect on tumour cell lines in comparison with embryonal murine fibroblasts (3T3). When evaluating their antiviral activity, the 3-deazapurine derivative of l-AA (3) exhibited the highest activity against both laboratory-adapted strains of human cytomegalovirus (HCMV) (AD-169 and Davis) with EC50 values comparable to those of the well-known anti-HCMV drug ganciclovir and without cytotoxic effects on normal human embryonal lung (HEL) cells.
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Affiliation(s)
- Maja Stipković Babić
- Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of Zagreb, Marulićev trg 20, HR-10000 Zagreb, Croatia
| | - Damjan Makuc
- Slovenian NMR Centre, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia; EN-FIST Centre of Excellence, Trg Osvobodilne fronte 13, SI-1000 Ljubljana, Slovenia
| | - Janez Plavec
- Slovenian NMR Centre, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia; EN-FIST Centre of Excellence, Trg Osvobodilne fronte 13, SI-1000 Ljubljana, Slovenia
| | - Tamara Martinović
- Department of Biotechnology, University of Rijeka, Radmile Matejčić 2, HR-51000 Rijeka, Croatia
| | | | - Krešimir Pavelić
- Department of Biotechnology, University of Rijeka, Radmile Matejčić 2, HR-51000 Rijeka, Croatia
| | - Robert Snoeck
- Department of Microbiology and Immunology, Rega Institute for Medical Research, Katholieke Universiteit Leuven, Minderbroedersstraat 10, B-3000 Leuven, Belgium
| | - Graciela Andrei
- Department of Microbiology and Immunology, Rega Institute for Medical Research, Katholieke Universiteit Leuven, Minderbroedersstraat 10, B-3000 Leuven, Belgium
| | - Dominique Schols
- Department of Microbiology and Immunology, Rega Institute for Medical Research, Katholieke Universiteit Leuven, Minderbroedersstraat 10, B-3000 Leuven, Belgium
| | - Karlo Wittine
- Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of Zagreb, Marulićev trg 20, HR-10000 Zagreb, Croatia
| | - Mladen Mintas
- Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of Zagreb, Marulićev trg 20, HR-10000 Zagreb, Croatia.
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Affiliation(s)
- J D Finkelstein
- Department of Veterans Affairs Medical Center and George Washington University School of Medicine, Washington, DC, USA
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Gordon RK, Ginalski K, Rudnicki WR, Rychlewski L, Pankaskie MC, Bujnicki JM, Chiang PK. Anti-HIV-1 activity of 3-deaza-adenosine analogs. Inhibition of S-adenosylhomocysteine hydrolase and nucleotide congeners. EUROPEAN JOURNAL OF BIOCHEMISTRY 2003; 270:3507-17. [PMID: 12919315 DOI: 10.1046/j.1432-1033.2003.03726.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Eight adenosine analogs, 3-deaza-adenosine (DZA), 3-deaza-(+/-)aristeromycin (DZAri), 2',3'-dideoxy-adenosine (ddAdo), 2',3'-dideoxy-3-deaza-adenosine (ddDZA), 2',3'-dideoxy-3-deaza-(+/-)aristeromycin (ddDZAri), 3-deaza-5'-(+/-)noraristeromycin (DZNAri), 3-deaza-neplanocin A (DZNep), and neplanocin A (NepA), were tested as inhibitors of human placenta S-adenosylhomocysteine (AdoHcy) hydrolase. The order of potency for the inhibition of human placental AdoHcy hydrolase was: DZNep approximately NepA >> DZAri approximately DZNAri > DZA >> ddAdo approximately ddDZA approximately ddDZAri. These same analogs were examined for their anti-HIV-1 activities measured by the reduction in p24 antigen produced by 3'-azido-3'-deoxythymidine (AZT)-sensitive HIV-1 isolates, A012 and A018, in phytohemagglutinin-stimulated peripheral blood mononuclear (PBMCs) cells. Interestingly, DZNAri and the 2',3'-dideoxy 3-deaza-nucleosides (ddAdo, ddDZAri, and ddDZA) were only marginal inhibitors of p24 antigen production in HIV-1 infected PBMC. DZNAri is unique because it is the only DZA analog with a deleted methylene group that precludes anabolic phosphorylation. In contrast, the other analogs were potent inhibitors of p24 antigen production by both HIV-1 isolates. Thus it was postulated that these nucleoside analogs could exert their antiviral effect via a combination of anabolically generated nucleotides (with the exception of DZNAri), which could inhibit reverse transcriptase or other viral enzymes, and the inhibition of viral or cellular methylation reactions. Additionally, QSAR-like models based on the molecular mechanics (MM) were developed to predict the order of potency of eight adenosine analogs for the inhibition of human AdoHcy hydrolase. In view of the potent antiviral activities of the DZA analogs, this approach provides a promising tool for designing and screening of more potent AdoHcy hydrolase inhibitors and antiviral agents.
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James SJ, Melnyk S, Pogribna M, Pogribny IP, Caudill MA. Elevation in S-adenosylhomocysteine and DNA hypomethylation: potential epigenetic mechanism for homocysteine-related pathology. J Nutr 2002; 132:2361S-2366S. [PMID: 12163693 DOI: 10.1093/jn/132.8.2361s] [Citation(s) in RCA: 240] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Chronic nutritional deficiencies in folate, choline, methionine, vitamin B-6 and/or vitamin B-12 can perturb the complex regulatory network that maintains normal one-carbon metabolism and homocysteine homeostasis. Genetic polymorphisms in these pathways can act synergistically with nutritional deficiencies to accelerate metabolic pathology associated with occlusive heart disease, birth defects and dementia. A major unanswered question is whether homocysteine is causally involved in disease pathogenesis or whether homocysteinemia is simply a passive and indirect indicator of a more complex mechanism. S-Adenosylmethionine and S-adenosylhomocysteine (SAH), as the substrate and product of methyltransferase reactions, are important metabolic indicators of cellular methylation status. Chronic elevation in homocysteine levels results in parallel increases in intracellular SAH and potent product inhibition of DNA methyltransferases. SAH-mediated DNA hypomethylation and associated alterations in gene expression and chromatin structure may provide new hypotheses for pathogenesis of diseases related to homocysteinemia.
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Affiliation(s)
- S Jill James
- Division of Biochemical Toxicology, National Center for Toxicological Research, Jefferson, AR 72079, USA.
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Smee DF, Bray M, Huggins JW. Intracellular phosphorylation of carbocyclic 3-deazaadenosine, an anti-Ebola virus agent. Antivir Chem Chemother 2001; 12:251-8. [PMID: 11771734 DOI: 10.1177/095632020101200406] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Carbocyclic 3-deazaadenosine (C-c3Ado) is a potent inhibitor of Ebola virus in mice by infrequent dosing, even though its half life in plasma is only 23-28 min. This prompted studies to determine whether C-c3Ado undergoes intracellular metabolism to derivatives that may promote in vivo activity. In cells, radiolabelled compound readily underwent metabolism to monophosphate, diphosphate and triphosphate (C-c3ATP) forms, with C-c3ATP being the major metabolite detected. A non-polar metabolite was also detected both inside and outside treated cells. The retention time of C-c3ATP was similar but not identical to ATP on a strong anion exchange high performance liquid chromatography (HPLC) column or on a DEAE-Sephadex open column. C-c3ATP and ATP were susceptible to degradation to their respective nucleosides by bovine alkaline phosphatase. Intracellular formation of C-c3ATP reached a plateau by about 4 h after treatment of monkey (Vero 76) and mouse (Balb/3T3 clone A31) cells with 10 or 100 microM extracellular compound. Phosphorylation was linearly dose responsive at 1, 3 and 10 microM. However, the extent of phosphorylation decreased with increasingly higher concentrations (30, 100 and 300 microM). When compound was removed from the medium, the nucleoside cleared the cells within 1 min, whereas C-c3ATP had a half life of decay of 2-3 h in five cell lines. Phosphorylation of C-c3Ado to C-c3ATP was not inhibited by cotreatment of cells (at a 20:1 ratio) with adenosine, guanosine, inosine, xanthosine, cytidine or uridine. There was no evidence of incorporation of C-c3Ado (10 microM) into macromolecules of cells over 72 h, whereas adenosine was readily incorporated. C-c3ATP may represent a form of C-c3Ado that might contribute to extending its intracellular half life or otherwise exhibit antiviral activity and/or toxicity.
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Affiliation(s)
- D F Smee
- Virology Division, US Army Medical Research Institute of Infectious Diseases, Frederick, MD, USA.
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Yi P, Melnyk S, Pogribna M, Pogribny IP, Hine RJ, James SJ. Increase in plasma homocysteine associated with parallel increases in plasma S-adenosylhomocysteine and lymphocyte DNA hypomethylation. J Biol Chem 2000; 275:29318-23. [PMID: 10884384 DOI: 10.1074/jbc.m002725200] [Citation(s) in RCA: 461] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
S-Adenosylmethionine and S-adenosylhomocysteine (SAH), as the substrate and product of essential cellular methyltransferase reactions, are important metabolic indicators of cellular methylation status. Chronic elevation of SAH, secondary to the homocysteine-mediated reversal of the SAH hydrolase reaction, reduces methylation of DNA, RNA, proteins, and phospholipids. High affinity binding of SAH to the active site of cellular methyltransferases results in product inhibition of the enzyme. Using a sensitive new high pressure liquid chromatography method with coulometric electrochemical detection, plasma SAH levels in healthy young women were found to increase linearly with mild elevation in homocysteine levels (r = 0.73; p < 0.001); however, S-adenosylmethionine levels were not affected. Plasma SAH levels were positively correlated with intracellular lymphocyte SAH levels (r = 0.81; p < 0.001) and also with lymphocyte DNA hypomethylation (r = 0.74, p < 0.001). These results suggest that chronic elevation in plasma homocysteine levels, such as those associated with nutritional deficiencies or genetic polymorphisms in the folate pathway, may have an indirect and negative effect on cellular methylation reactions through a concomitant increase in intracellular SAH levels.
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Affiliation(s)
- P Yi
- Division of Biochemical Toxicology, FDA-National Center for Toxicological Research, Jefferson, Arkansas 72079, USA
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Melnyk S, Pogribna M, Pogribny IP, Yi P, James SJ. Measurement of Plasma and Intracellular S-Adenosylmethionine and S-Adenosylhomocysteine Utilizing Coulometric Electrochemical Detection: Alterations with Plasma Homocysteine and Pyridoxal 5′-Phosphate Concentrations. Clin Chem 2000. [DOI: 10.1093/clinchem/46.2.265] [Citation(s) in RCA: 155] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
AbstractBackground: The relative changes in plasma and intracellular concentrations of S-adenosylmethionine (SAM) and S-adenosylhomocysteine (SAH) may be important predictors of cellular methylation potential and metabolic alterations associated with specific genetic polymorphisms and/or nutritional deficiencies. Because these metabolites are present in nanomolar concentrations in plasma, methods of detection generally require time-consuming precolumn processing or metabolite derivatization.Methods: We used HPLC with coulometric electrochemical detection for the simultaneous measurement of SAM and SAH in 200 μL of plasma, 106 lymphocytes, or 10 mg of tissue. Filtered trichloroacetic acid extracts were injected directly into the HPLC system without additional processing and were eluted isocratically.Results: The limits of detection were 200 fmol/L for SAM and 40 fmol/L SAH. In plasma extracts, the interassay CV was 3.4–5.5% and the intraassay CV was 2.8–5.6%. The analytical recoveries were 96.8% and 97.3% for SAM and SAH, respectively. In a cohort of healthy adult women with mean total homocysteine concentrations of 7.3 μmol/L, the mean plasma value was 156 nmol/L for SAM and 20 nmol/L for SAH. In women with increased homocysteine concentrations (mean, 12.1 μmol/L), plasma SAH, but not SAM, was increased (P <0.001), and plasma pyridoxal 5′-phosphate concentrations were reduced (P <0.001). Plasma SAM/SAH ratios were inversely correlated with homocysteine concentrations (r = 0.73; P <0.01), and the SAM/SAH ratio in plasma was directly correlated with the intracellular SAM/SAH ratio in lymphocytes (r = 0.70; P <0.01).Conclusions: Increased homocysteine in serum is associated with an increase in SAH and a decrease in the SAM/SAH ratio that could negatively affect cellular methylation potential. Accurate and sensitive detection of these essential metabolites in plasma and in specific tissues should provide new insights into the regulation of one-carbon metabolism under different nutritional and pathologic conditions.
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Affiliation(s)
- Stepan Melnyk
- Division of Biochemical Toxicology, National Center for Toxicological Research, 3900 NCTR Rd., Jefferson, AR 72079
| | - Marta Pogribna
- Division of Biochemical Toxicology, National Center for Toxicological Research, 3900 NCTR Rd., Jefferson, AR 72079
| | - Igor P Pogribny
- Division of Biochemical Toxicology, National Center for Toxicological Research, 3900 NCTR Rd., Jefferson, AR 72079
| | - Ping Yi
- Division of Biochemical Toxicology, National Center for Toxicological Research, 3900 NCTR Rd., Jefferson, AR 72079
| | - S Jill James
- Division of Biochemical Toxicology, National Center for Toxicological Research, 3900 NCTR Rd., Jefferson, AR 72079
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Hershfield MS. IMMUNODEFICIENCY CAUSED BY ADENOSINE DEAMINASE DEFICIENCY. Radiol Clin North Am 2000. [DOI: 10.1016/s0033-8389(22)00185-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Affiliation(s)
- R Resta
- Immunobiology and Cancer Program, Oklahoma Medical Research Foundation, Oklahoma City 73104, USA. regina
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Hershfield MS, Arredondo-Vega FX, Santisteban I. Clinical expression, genetics and therapy of adenosine deaminase (ADA) deficiency. J Inherit Metab Dis 1997; 20:179-85. [PMID: 9211190 DOI: 10.1023/a:1005300621350] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Adenosine deaminase (ADA) deficiency was the first known cause of primary immunodeficiency. Over the past 25 years the basis for immune deficiency has largely been established. Now it appears that ADA deficiency may also cause hepatic toxicity, raising new questions about its pathogenesis. The ADA gene has been sequenced and the ADA three-dimensional structure solved. The relationship between genotype and phenotype is being analysed, and ADA deficiency has become a focus for novel approaches to enzyme replacement and gene therapy.
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Affiliation(s)
- M S Hershfield
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
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Migchielsen AA, Breuer ML, van Roon MA, te Riele H, Zurcher C, Ossendorp F, Toutain S, Hershfield MS, Berns A, Valerio D. Adenosine-deaminase-deficient mice die perinatally and exhibit liver-cell degeneration, atelectasis and small intestinal cell death. Nat Genet 1995; 10:279-87. [PMID: 7670465 DOI: 10.1038/ng0795-279] [Citation(s) in RCA: 102] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We report the generation and characterization of mice lacking adenosine deaminase (ADA). In humans, absence of ADA causes severe combined immunodeficiency. In contrast, ADA-deficient mice die perinatally with marked liver-cell degeneration, but lack abnormalities in the thymus. The ADA substrates, adenosine and deoxyadenosine, are increased in ADA-deficient mice. Adenine deoxyribonucleotides are only modestly elevated, whereas S-adenosylhomocysteine hydrolase activity is reduced more than 85%. Consequently, the ratio of S-adenosylhomocysteine (AdoMet) to S-adenosyl homocysteine (AdoHcy) is reduced threefold in liver. We conclude that ADA plays a more critical role in murine than human fetal development. The murine liver pathology may be due to AdoHcy-mediated inhibition of AdoMet-dependent transmethylation reactions.
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Affiliation(s)
- A A Migchielsen
- Laboratory for Molecular Carcinogenesis, Sylvius Laboratories, Leiden University, The Netherlands
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Haaf T. The effects of 5-azacytidine and 5-azadeoxycytidine on chromosome structure and function: implications for methylation-associated cellular processes. Pharmacol Ther 1995; 65:19-46. [PMID: 7536332 DOI: 10.1016/0163-7258(94)00053-6] [Citation(s) in RCA: 134] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
5-Azacytidine (5-aza-C) analogs demonstrate a remarkable ability to induce heritable changes in gene and phenotypic expression. These cellular processes are associated with the demethylation of specific DNA sequences. On the other hand, 5-aza-C analogs have dramatic effects on chromosomes, leading to decondensation of chromatin structure, chromosomal instability and an advance in replication timing. Condensation inhibition of genetically inactive chromatin occurs when the DNA is still hemimethylated or fully methylated. In cell cultures prolonged for several replication cycles, chromosomal rearrangements and instability affect the 5-aza-C-sensitive regions. Moreover, the normally late-replicating inactive chromatin undergoes a transient temporal shift to an earlier DNA replication, characteristic of activatable chromatin. zThe induced alterations of chromosome structure and behavior may trigger the 5-aza-C-dependent process of cellular reprogramming. Apart from their differentiating and gene-modifying effects, 5-aza-C analogs can tumorigenically transform cells and modulate their metastatic potential. High doses of 5-aza-C analogs have cytotoxic and antineoplastic activities.
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Affiliation(s)
- T Haaf
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06520-80050
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Henderson DM, Hanson S, Allen T, Wilson K, Coulter-Karis DE, Greenberg ML, Hershfield MS, Ullman B. Cloning of the gene encoding Leishmania donovani S-adenosylhomocysteine hydrolase, a potential target for antiparasitic chemotherapy. Mol Biochem Parasitol 1992; 53:169-83. [PMID: 1501636 DOI: 10.1016/0166-6851(92)90019-g] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A full-length gene encoding the S-adenosylhomocysteine hydrolase (AdoHcyase) enzyme has been isolated from a genomic library of Leishmania donovani DNA in lambda GEM-11 by cross-hybridization to the full-length human AdoHcyase cDNA. The nucleotide sequence of the SalI fragment contained a single open reading frame that encoded a polypeptide of 438 amino acids (47,712 Da). After maximum gap alignment, the predicted amino acid sequence of the leishmanial AdoHcyase was 70-73% identical to AdoHCyases from higher eukaryotes. In addition, a data base search revealed that the primary structure of all AdoHcyase proteins was highly homologous to that of a protein encoded by a mRNA from Drosophila melanogaster that maps near the r element function of the Abd-b homeotic gene. In Northern blots, the SalI fragment hybridized to a 3.0-kb transcript that presumably encodes the parasite enzyme. Southern blot analysis of genomic DNA revealed that the AdoHcyase gene did not exist as a tandemly repeated array within the L. donovani genome. Moreover, monoclonal antibodies generated against human AdoHcyase recognized a leishmanial protein on immunoblots. Finally, the growth of L. donovani promastigotes could be arrested by micromolar concentrations of 3-deazaaristeromycin (C3Ari) and 9-(trans-2',trans-3'-dihydroxycyclopentanyl)adenine, 2 known inhibitors of mammalian AdoHcyase. C3Ari also induced a substantial expansion of the intracellular pools of both AdoHcy and S-adenosylmethionine (AdoMet), as well as a significant diminution of the AdoMet/AdoHcy ratio. Thus, AdoHcyase may have therapeutic potential for the selective treatment of diseases of parasitic origin.
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Affiliation(s)
- D M Henderson
- Department of Biochemistry and Molecular Biology, Oregon Health Sciences University, Portland 97201-3098
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Exon skipping in purine nucleoside phosphorylase mRNA processing leading to severe immunodeficiency. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(18)42589-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Chiang P, Burbelo P, Brugh S, Gordon R, Fukuda K, Yamada Y. Activation of collagen IV gene expression in F9 teratocarcinoma cells by 3-deazaadenosine analogs. Indirect inhibitors of methylation. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(18)42928-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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