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Aoki MM, Seegobin M, Kisiala A, Noble A, Brunetti C, Emery RJN. Phytohormone metabolism in human cells: Cytokinins are taken up and interconverted in HeLa cell culture. FASEB Bioadv 2019; 1:320-331. [PMID: 32123835 PMCID: PMC6996375 DOI: 10.1096/fba.2018-00032] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 02/06/2019] [Accepted: 02/07/2019] [Indexed: 01/30/2023] Open
Abstract
Cytokinins (CKs) encompass a group of phytohormones, known to orchestrate many critical processes in plant development. Excluding Archaea, CKs are pervasive among all kingdoms, but much less is reported about their metabolism beyond plants. Recent evidence from mammalian tissues indicates the presence of six additional CK forms beyond the previously identified, single mammalian CK, N6-isopentenyladenosine (i6A). There is limited understanding of CK biosynthesis pathways in mammalian systems; therefore, human cervical cancer (HeLa) cells were used to further characterize CK processing by tracking the interconversion of CKs into their various structural derivatives in mammalian cells in a time-course study. Through high-performance liquid chromatography-positive electrospray ionization-tandem mass spectrometry (HPLC-(+ESI)-MS/MS), we document changes in the functional profiles of endogenous CKs in a human cell line following metabolism by HeLa cell cultures. The nucleotide CK fraction (iPRP) was found exclusively within the cell pellet (0.34 pmol/106 cells), and the active free base (FB) form (iP) and riboside fraction (iPR) were found in greater abundance extracellularly (1.67 and 0.10 nmol/L respectively). For further confirmation, we demonstrate that HeLa cells metabolize an exogenously supplied CK, N6-benzyladenosine (BAR). In the HeLa culture supernatant, a 12-fold decrease in BAR concentration was observed within the first 24 hours of incubation accompanied by a fivefold increase in the FB form, N6-benzyladenine (BA). These findings support the hypothesis that HeLa cells have the enzymatic pathways required for the metabolism of both endogenous and exogenous CKs.
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Affiliation(s)
- Megan M. Aoki
- Department of BiologyTrent UniversityPeterboroughOntarioCanada
| | - Mark Seegobin
- Department of BiologyTrent UniversityPeterboroughOntarioCanada
| | - Anna Kisiala
- Department of BiologyTrent UniversityPeterboroughOntarioCanada
| | | | - Craig Brunetti
- Department of BiologyTrent UniversityPeterboroughOntarioCanada
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Ashihara H, Stasolla C, Fujimura T, Crozier A. Purine salvage in plants. PHYTOCHEMISTRY 2018; 147:89-124. [PMID: 29306799 DOI: 10.1016/j.phytochem.2017.12.008] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 12/10/2017] [Accepted: 12/14/2017] [Indexed: 05/04/2023]
Abstract
Purine bases and nucleosides are produced by turnover of nucleotides and nucleic acids as well as from some cellular metabolic pathways. Adenosine released from the S-adenosyl-L-methionine cycle is linked to many methyltransferase reactions, such as the biosynthesis of caffeine and glycine betaine. Adenine is produced by the methionine cycles, which is related to other biosynthesis pathways, such those for the production of ethylene, nicotianamine and polyamines. These purine compounds are recycled for nucleotide biosynthesis by so-called "salvage pathways". However, the salvage pathways are not merely supplementary routes for nucleotide biosynthesis, but have essential functions in many plant processes. In plants, the major salvage enzymes are adenine phosphoribosyltransferase (EC 2.4.2.7) and adenosine kinase (EC 2.7.1.20). AMP produced by these enzymes is converted to ATP and utilised as an energy source as well as for nucleic acid synthesis. Hypoxanthine, guanine, inosine and guanosine are salvaged to IMP and GMP by hypoxanthine/guanine phosphoribosyltransferase (EC 2.4.2.8) and inosine/guanosine kinase (EC 2.7.1.73). In contrast to de novo purine nucleotide biosynthesis, synthesis by the salvage pathways is extremely favourable, energetically, for cells. In addition, operation of the salvage pathway reduces the intracellular levels of purine bases and nucleosides which inhibit other metabolic reactions. The purine salvage enzymes also catalyse the respective formation of cytokinin ribotides, from cytokinin bases, and cytokinin ribosides. Since cytokinin bases are the active form of cytokinin hormones, these enzymes act to maintain homeostasis of cellular cytokinin bioactivity. This article summarises current knowledge of purine salvage pathways and their possible function in plants and purine salvage activities associated with various physiological phenomena are reviewed.
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Affiliation(s)
- Hiroshi Ashihara
- Department of Biology, Ochanomizu University, Bunkyo-ku, Tokyo, 112-8610, Japan.
| | - Claudio Stasolla
- Department of Plant Science, University of Manitoba, Winnipeg, R3T 2N2, Canada
| | - Tatsuhito Fujimura
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, 305-8572, Japan
| | - Alan Crozier
- Department of Nutrition, University of California, Davis, CA, 95616-5270, USA
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Galazka J, Striepen B, Ullman B. Adenosine kinase from Cryptosporidium parvum. Mol Biochem Parasitol 2006; 149:223-30. [PMID: 16879885 DOI: 10.1016/j.molbiopara.2006.06.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2006] [Revised: 06/05/2006] [Accepted: 06/06/2006] [Indexed: 10/24/2022]
Abstract
Analysis of the Cryptosporidium parvum genome demonstrates that the parasite cannot synthesize purines de novo and reveals that the sole route for purine salvage by the parasite is via adenosine kinase (CpAK). In order to initiate a biochemical characterization of CpAK and ultimately validate this apparently essential enzyme as a therapeutic target, the CpAK gene was redesigned for optimum codon usage, overexpressed in Escherichia coli, and the recombinant protein purified to homogeneity and characterized. CpAK appears to be specific for adenosine among the naturally occurring nucleosides but can utilize ATP, GTP, UTP and CTP as the phosphate donor. The enzyme exhibits K(m) values of 1.4microM for adenosine and 41microM for ATP, has a pH optimum approximately 7.0, and is dependent upon the presence of a divalent cation. Structure-activity data intimate that catalysis requires contacts between residues on CpAK with the six-position of the purine ring and the O2' and O3' hydroxyls of the ribose sugar. Additionally, 4-nitro-6-benzylthioinosine, a compound that demonstrates therapeutic promise against the related parasite Toxoplasma gondii, also inhibits adenosine phosphorylation by CpAK. The overproduction and purification of CpAK now enables a thorough evaluation of its potential as a drug target.
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Affiliation(s)
- Jon Galazka
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, OR 97239-3098, USA
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Datta R, Das I, Sen B, Chakraborty A, Adak S, Mandal C, Datta A. Homology-model-guided site-specific mutagenesis reveals the mechanisms of substrate binding and product-regulation of adenosine kinase from Leishmania donovani. Biochem J 2006; 394:35-42. [PMID: 16271040 PMCID: PMC1386000 DOI: 10.1042/bj20051513] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Despite designating catalytic roles of Asp299 and Arg131 during the transfer of gamma-phosphate from ATP to Ado (adenosine) [R. Datta, Das, Sen, Chakraborty, Adak, Mandal and A. K. Datta (2005) Biochem. J. 387, 591-600], the mechanisms that determine binding of substrate and cause product inhibition of adenosine kinase from Leishmania donovani remained unclear. In the present study, employing homology-model-guided site-specific protein mutagenesis, we show that Asp16 is indispensable, since its replacement with either valine or arginine resulted in a >200-fold increase in K(m) (Ado) with a 1000-fold decrease in k(cat)/K(m), implying its critical importance in Ado binding. Even glutamate replacement was not tolerated, indicating the essentiality of Asp16 in the maintenance of steric complementarity of the binding pocket. Use of 2'or 3'-deoxygenated Ado as substrates indicated that, although both the hydroxy groups play important roles in the formation of the enzyme-Ado complex, the binding energy (DeltaDeltaG(B)) contribution of the former was greater than the latter, suggesting possible formation of a bidentate hydrogen bond between Asp16 and the adenosyl ribose. Interestingly, AMP-inhibition and AMP-binding studies revealed that, unlike the R131A mutant, which showed abrogated AMP-binding and insensitivity towards AMP inhibition despite its unaltered K(m) (Ado), all the Asp16 mutants bound AMP efficiently and displayed AMP-sensitive catalytic activity, suggesting disparate mechanisms of binding of Ado and AMP. Molecular docking revealed that, although both Ado and AMP apparently occupied the same binding pocket, Ado binds in a manner that is subtly different from AMP binding, which relies heavily on hydrogen-bonding with Arg131 and thus creates an appropriate environment for competition with Ado. Hence, besides its role in catalysis, an additional novel function of the Arg131 residue as an effector of product-mediated enzyme regulation is proposed.
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Affiliation(s)
- Rupak Datta
- *Division of Infectious Diseases, Leishmania Group, Indian Institute of Chemical Biology, 4 Raja S.C. Mullick Road, Kolkata 700032, India
| | - Ishita Das
- *Division of Infectious Diseases, Leishmania Group, Indian Institute of Chemical Biology, 4 Raja S.C. Mullick Road, Kolkata 700032, India
| | - Banibrata Sen
- *Division of Infectious Diseases, Leishmania Group, Indian Institute of Chemical Biology, 4 Raja S.C. Mullick Road, Kolkata 700032, India
| | - Anutosh Chakraborty
- *Division of Infectious Diseases, Leishmania Group, Indian Institute of Chemical Biology, 4 Raja S.C. Mullick Road, Kolkata 700032, India
| | - Subrata Adak
- *Division of Infectious Diseases, Leishmania Group, Indian Institute of Chemical Biology, 4 Raja S.C. Mullick Road, Kolkata 700032, India
| | - Chhabinath Mandal
- †Division of Drug Design, Development and Molecular Modeling, Indian Institute of Chemical Biology, 4 Raja S.C. Mullick Road, Kolkata 700032, India
| | - Alok K. Datta
- *Division of Infectious Diseases, Leishmania Group, Indian Institute of Chemical Biology, 4 Raja S.C. Mullick Road, Kolkata 700032, India
- To whom correspondence should be addressed (email )
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Moffatt BA, Wang L, Allen MS, Stevens YY, Qin W, Snider J, von Schwartzenberg K. Adenosine kinase of Arabidopsis. Kinetic properties and gene expression. PLANT PHYSIOLOGY 2000; 124:1775-85. [PMID: 11115893 PMCID: PMC59874 DOI: 10.1104/pp.124.4.1775] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2000] [Revised: 05/22/2000] [Accepted: 07/18/2000] [Indexed: 05/17/2023]
Abstract
To assess the functional significance of adenosine salvage in plants, the cDNAs and genes encoding two isoforms of adenosine kinase (ADK) were isolated from Arabidopsis. The ADK1- and ADK2-coding sequences are very similar, sharing 92% and 89% amino acid and nucleotide identity, respectively. Each cDNA was overexpressed in Escherichia coli, and the catalytic activity of each isoform was determined. Both ADKs had similar catalytic properties with a K(m) and V(max)/K(m) for adenosine of 0.3 to 0.5 microM and 5.4 to 22 L min(-1) mg(-1) protein, respectively. The K(m) and V(max)/K(m) for the cytokinin riboside N(6)(isopentenyl) adenosine are 3 to 5 microM and 0.021 to 0.14 L min(-1) mg(-1) protein, respectively, suggesting that adenosine is the preferred substrate for both ADK isoforms. In Arabidopsis plants, both ADK genes are expressed constitutively, with the highest steady-state mRNA levels being found in stem and root. ADK1 transcript levels were generally higher than those of ADK2. ADK enzyme activity reflected relative ADK protein levels seen in immunoblots for leaves, flowers, and stems but only poorly so for roots, siliques, and dry seeds. The catalytic properties, tissue accumulation, and expression levels of these ADKs suggest that they play a key metabolic role in the salvage synthesis of adenylates and methyl recycling in Arabidopsis. They may also contribute to cytokinin interconversion.
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MESH Headings
- Adenosine/metabolism
- Adenosine Kinase/genetics
- Adenosine Kinase/metabolism
- Arabidopsis/enzymology
- Arabidopsis/genetics
- Blotting, Northern
- Cytokinins/metabolism
- DNA, Complementary/chemistry
- DNA, Complementary/genetics
- DNA, Complementary/isolation & purification
- DNA, Plant/chemistry
- DNA, Plant/genetics
- DNA, Plant/isolation & purification
- Gene Expression Regulation, Enzymologic
- Gene Expression Regulation, Plant
- Genes, Plant/genetics
- Isoenzymes/genetics
- Isoenzymes/metabolism
- Kinetics
- Molecular Sequence Data
- Phylogeny
- Promoter Regions, Genetic
- RNA, Plant/genetics
- RNA, Plant/metabolism
- Sequence Analysis, DNA
- Substrate Specificity
- Tissue Distribution
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Affiliation(s)
- B A Moffatt
- Department of Biology, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1.
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Matsumoto S, Kuroda Y, Hamano M, Kim Y, Suzuki Y, Ku Y, Saitoh Y. Direct evidence of pancreatic tissue oxygenation during preservation by the two-layer method. Transplantation 1996; 62:1667-70. [PMID: 8970625 DOI: 10.1097/00007890-199612150-00023] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The purpose of this study was to measure directly tissue oxygen tension (PO2) of the ischemically damaged pancreas graft during preservation by the two-layer (University of Wisconsin solution/perfluoro-chemical) method at 20 degrees C using Clark-type polarographic oxygen electrodes and to make clear the relationship of tissue PO2 and ATP levels during preservation and graft survival after transplantation in a canine model. During warm ischemia, tissue PO2 and ATP were dramatically decreased. Tissue PO2 continued to decrease, and tissue ATP levels were not elevated during simple storage in oxygenated University of Wisconsin solution at 20 degrees C. On the contrary, during preservation by the two-layer method at 20 degrees C, tissue PO2 promptly increased and reached about 50% of the preprocurement level at 30 min of preservation. Then, tissue PO2 was maintained this level throughout the preservation period. Tissue ATP levels were still low in the first 1 hr, but after that tissue ATP increased in a time-dependent manner. Consequently, the two-layer method at 20 degrees C could restore the viability of pancreas damaged by warm ischemia during 3- and 5-hr preservation. We conclude that the ischemically damaged pancreas grafts were oxygenated, and tissue ATP was increased during preservation by the two-layer (University of Wisconsin solution/pefluorochemical) method at 20 degrees C. Consequently, the graft was resuscitated and survived after transplantation.
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Affiliation(s)
- S Matsumoto
- First Department of Surgery, Kobe University School of Medicine, Japan
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8
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Kuroda Y, Matsumoto S, Fujita H, Tanioka Y, Sakai T, Hamano M, Hiraoka K, Kim Y, Suzuki Y, Ku Y, Saitoh Y. Resuscitation of ischemically damaged pancreas during short-term preservation at 20 degrees C by the two-layer (University of Wisconsin solution/perfluorochemical) method. Transplantation 1996; 61:28-30. [PMID: 8560568 DOI: 10.1097/00007890-199601150-00007] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We have shown that 24-hr preservation by a two-layer (University of Wisconsin solution [UW]/perfluorochemical [PFC]) cold storage method allows tissue ATP synthesis and makes it possible to resuscitate a canine pancreas subjected to 90 min of warm ischemia. The purpose of this study was to examine whether increasing preservation temperature to 20 degrees C makes it possible to shorten a preservation period for recovery of ischemically damaged pancreas grafts. After 90 min of warm ischemia, canine pancreas grafts were preserved using the two-layer (UW/PFC) method for 1 to 8 hr at 20 degrees C, and then autotransplanted. A K-value of intravenous glucose tolerance test more than 1.0 at 2 weeks after transplantation was considered graft survival. ATP tissue levels were measured by high performance liquid chromatography at the end of preservation. Pancreatic tissue perfusions were measured using an H2 clearance technique after 30 min to 4 hr of reperfusion. Pancreas grafts subjected to 90 min of warm ischemia were not viable (0/5, control group). However, 3- and 5-hr preservations made it possible to recover the ischemically damaged pancreas (3/5 and 5/5, respectively), although 1- and 8-hr preservations were not successful (0/3 and 0/3, respectively). ATP tissue levels in 1-hr-preserved grafts were 2.55 +/- 0.38 mumol/g dry weight and were significantly lower compared with the levels in 5- and 8-hr-preserved grafts, 9.40 +/- 2.09 (P < 0.01) and 7.37 +/- 1.06 (P < 0.01), respectively. On the other hand, pancreatic tissue perfusions in 8-hr-preserved grafts after 2 hr of reperfusion were 28.50 +/- 7.52 ml/100 g/min and were significantly lower than the values in 1- and 5-hr-preserved grafts, 66.0 +/- 11.22 (P < 0.01) and 57.10 +/- 4.40 (P < 0.01), respectively. It was suggested that 1-hr-preservation was not enough to synthesize ATP, which was essential to repair damaged cells, although vascular microcirculation at reperfusion was maintained and 8-hr preservation incurred microcirculatory disturbances, although ATP for repairing damaged cells was synthesized. We conclude that 3- to 5-hr preservation at 20 degrees C by the two-layer (UW/PFC) method accelerates ATP synthesis, which is essential for repairing damaged cells and protects vascular microcirculation. This makes it possible to resuscitate ischemically damaged pancreases faster. This method holds promise for pancreas-kidney transplantation from cardiac arrest donors.
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Affiliation(s)
- Y Kuroda
- First Department of Surgery, Kobe University School of Medicine, Japan
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9
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Datta A, Bhaumik D, Chatterjee R. Isolation and characterization of adenosine kinase from Leishmania donovani. J Biol Chem 1987. [DOI: 10.1016/s0021-9258(18)45602-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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10
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Yamada Y, Goto H, Ogasawara N. Differences of adenosine kinases from various mammalian tissues. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. B, COMPARATIVE BIOCHEMISTRY 1982; 71:367-72. [PMID: 6279355 DOI: 10.1016/0305-0491(82)90396-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
1. Adenosine kinases purified to homogeneity from various mammalian tissues have a monomeric structure, and their molecular weights were estimated around 40,000. 2. The enzyme activity per wet weight of tissue appears to vary from source to source, but the specific activities of the final enzyme preparations were alike, which were 6.3--7.8 mumol/min/mg protein. 3. No or small difference was observed in the kinetic properties among all seven adenosine kinases. 4. Some differences in structure were observed among five liver enzymes from human, rabbit, rat, mouse and Mongolian gerbil, but no difference was observed between the enzymes from human placenta and liver, or the enzymes from rat liver and brain.
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Abstract
Adenosine kinase (ATP: adenosine 5'-phosphotransferase, EC 2.7.1.20) has been purified to homogeneity from human liver. The yield was 55% of the initial activity with a final specific activity of 6.3 mumol/min per mg protein. The molecular weight was estimated as about 40 000 by Sephadex G-100 gel filtration and polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS). The enzyme catalyzed the phosphorylation of adenosine, deoxyadenosine, arabinoadenosine, inosine and ribavirin. The activity of deoxyadenosine phosphorylation was 18% of that of adenosine. The pH optimum profile was biphasic; a sharp pH optimum at pH 5.5 and a broad optimum at pH 7.5--8.5. The Km value for adenosine was 0.15 micrometer, and the activity was strongly inhibited at higher concentrations than 0.5 micrometer. ATP, dATP, GTP and dGTP were proved to be effective phosphate donors. Co2+ was more effective than Mg2+, and Ca2+, Mn2+, Fe2+ and Ni2+ showed about 50% of the activity for Mg2+. Some difference in structure between the adenosine kinase from human liver and that from rabbit or rat tissue, was observed by amino acid analysis and peptide mapping analysis.
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12
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Yamada Y, Goto H, Ogasawara N. Purification and properties of adenosine kinase from rat brain. BIOCHIMICA ET BIOPHYSICA ACTA 1980; 616:199-207. [PMID: 6260151 DOI: 10.1016/0005-2744(80)90138-2] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Adenosine kinase (ATP:adenosine 5'-phosphotransferase, EC 2.7.1.20) has been purified to apparent homogeneity from rat brain by (NH4)2SO4 fractionation, affinity chromatography on AMP-Sepharose 4B, gel filtration with Sephadex G-100, and DE-52 cellulose column chromatography. The yield was 56% of the initial activity with a final specific activity of 7.8 mumol/min per mg protein. The molecular weight was estimated as 38 000 by gel filtration with Sephadex G-100 and 41 000 by acrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS). The enzyme catalyzed the phosphorylation of adenosine, deoxyadenosine, arabinoadenosine, inosine and ribavirin. The activity of deoxyadenosine phosphorylation was 20% that of adenosine phosphorylation. The pH optimum profile was biphasic; a sharp pH optimum at pH 5.5 and a broad pH optimum at pH 7.5-8.5. The Km value for adenosine was 0.2 microM and the maximum activity was observed at 0.5 microM. At higher concentrations of adenosine, the activity was strongly inhibited. The Km value for ATP was 0.02 mM and that for Mg2+ was 0.1 mM. GTP, dGTP, dATP and UTP were also proved to be effective phosphate donors. Co2+ was as effective as Mg2+, and Ca2+, Mn2+ or Ni2+ showed about 50% of the activity for Mg2+. The kinase is quite unstable, but stable in the presence of a high concentration of salt; e.g., 0.15 M KCl.
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13
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Chang C, Brockman R, Bennett L. Adenosine kinase from L1210 cells. Purification and some properties of the enzyme. J Biol Chem 1980. [DOI: 10.1016/s0021-9258(19)85900-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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15
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Adenosine kinase from rabbit liver. I. Purification by affinity chromatography and properties. J Biol Chem 1979. [DOI: 10.1016/s0021-9258(17)30226-0] [Citation(s) in RCA: 67] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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16
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de Jong JW, Kalkman C. Myocardial adenosine kinase: activity and localization determined with rapid, radiometric assay. BIOCHIMICA ET BIOPHYSICA ACTA 1973; 320:388-96. [PMID: 4356298 DOI: 10.1016/0304-4165(73)90320-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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17
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Kaneti J. A molecular orbital study of the reaction catalysed by the enzyme adenosine kinase and its active site. J Theor Biol 1973; 38:169-79. [PMID: 4707773 DOI: 10.1016/0022-5193(73)90232-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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18
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Henderson JF, Mikoshiba A, Chu SY, Caldwell IC. Kinetic Studies of Adenosine Kinase from Ehrlich Ascites Tumor Cells. J Biol Chem 1972. [DOI: 10.1016/s0021-9258(19)45478-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Shimizu H, Tanaka S, Kodama T. Adenosine kinase of mammalian brain: partial purification and its role for the uptake of adenosine. J Neurochem 1972; 19:687-98. [PMID: 5030981 DOI: 10.1111/j.1471-4159.1972.tb01384.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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20
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Rossi A, Mandel P, Dessaux G. [Kinetics of the turnover of phosphate of free nucleotides in rat myocardial tissue]. ARCHIVES INTERNATIONALES DE PHYSIOLOGIE ET DE BIOCHIMIE 1972; 80:59-78. [PMID: 4111324 DOI: 10.3109/13813457209075228] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Affiliation(s)
- V C. De Sanchez
- Departamento de Bioquímica, Facultad de Medicina, Ciudad Universitaria, 20 D.F., México
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Meyskens FL, Williams HE. Adenosine metabolism in human erythrocytes. BIOCHIMICA ET BIOPHYSICA ACTA 1971; 240:170-9. [PMID: 5559973 DOI: 10.1016/0005-2787(71)90654-x] [Citation(s) in RCA: 90] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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23
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Landin RM, Moulé Y. Unequal 32P-labeling of 5'nucleotides in ribonucleic acids of different mammalian tissues. FEBS Lett 1970; 6:52-54. [PMID: 11947335 DOI: 10.1016/0014-5793(70)80041-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- R M. Landin
- Institut de Recherches Scientifiques sur le Cancer 94-, Villejuif, France
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Isselhard W, Hinzen DH, Geppert E, Mäurer W. [Effect of substrate supply on post-asphyctic restoration of adenine nucleotides in rabbit hearts in vivo]. Pflugers Arch 1970; 320:195-209. [PMID: 5529264 DOI: 10.1007/bf00587453] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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25
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Landin RM, Moulé Y, Aye P. Labeling of alpha-P of nucleoside triphosphates by in vivo incorporation of 32P in rat liver. EUROPEAN JOURNAL OF BIOCHEMISTRY 1969; 11:68-72. [PMID: 4311071 DOI: 10.1111/j.1432-1033.1969.tb00740.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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26
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Ipata PL. Inhibition of sheep brain 5-nucleotidase by nucleoside triphosphates. PROGRESS IN BRAIN RESEARCH 1968; 29:527-37. [PMID: 5735123 DOI: 10.1016/s0079-6123(08)64179-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Schnebli HP, Hill DL, Bennett LL. Purification and Properties of Adenosine Kinase from Human Tumor Cells of Type H. Ep. No. 2. J Biol Chem 1967. [DOI: 10.1016/s0021-9258(18)96008-4] [Citation(s) in RCA: 134] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Lindberg B, Klenow H, Hansen K. Some Properties of Partially Purified Mammalian Adenosine Kinase. J Biol Chem 1967. [DOI: 10.1016/s0021-9258(18)96277-0] [Citation(s) in RCA: 122] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Caldwell IC, Henderson JF, Paterson AR. The enzymic formation of 6-(methylmercapto)purine ribonucleoside 5'-phosphate. CANADIAN JOURNAL OF BIOCHEMISTRY 1966; 44:229-45. [PMID: 5940561 DOI: 10.1139/o66-027] [Citation(s) in RCA: 46] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
6-(Methylmercapto)purine ribonucleoside (Me6MPR) is efficiently phosphorylated in mouse tissues and in Ehrlich ascites carcinoma cells in vivo; tumor cells in vitro and cell-free extracts of the tumor also phosphorylate this analogue ribonucleoside. The product of this reaction has been identified by chemical and enzymatic methods and by its chromatographic behaviour as Me6MPR 5′-phosphate. The evidence presented in this report indicates that no other major metabolites of Me6MPR are formed.The phosphorylation of Me6MPR by cell-free tumor extracts requires ATP and Mn2+(or Mg2+), and evidence is presented that the reaction is probably mediated by adenosine kinase.Me-14C-6MPR is rapidly taken up by most mouse tissues following its intraperitoneal injection. Forty minutes after injection of the labeled drug, the highest levels of radioactivity were found in intestine, liver, blood cells, lung, and spleen, in descending order; virtually no radioactivity was found in brain tissue or in blood plasma.
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Aikawa T. Adenosine aminohydrolase from the clam, Meretrix meretrix Lusoria (Gmelin). COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY 1966; 17:271-84. [PMID: 5940088 DOI: 10.1016/0010-406x(66)90026-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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MOAT AG, FRIEDMAN H. THE BIOSYNTHESIS AND INTERCONVERSION OF PURINES AND THEIR DERIVATIVES. BACTERIOLOGICAL REVIEWS 1960; 24:309-39. [PMID: 13771577 PMCID: PMC441056 DOI: 10.1128/br.24.3.309-339.1960] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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BOMSTEIN RA, STEBERL EA. The effect of adenosine upon the aerobic metabolism of bovine spermatozoa. Arch Biochem Biophys 1959; 85:43-52. [PMID: 13802418 DOI: 10.1016/0003-9861(59)90445-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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KORNBERG A. Pyrophosphorylases and phosphorylases in biosynthetic reactions. ADVANCES IN ENZYMOLOGY AND RELATED SUBJECTS OF BIOCHEMISTRY 1957; 18:191-240. [PMID: 13444110 DOI: 10.1002/9780470122631.ch5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
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[76] Adenosine phosphokinase. Methods Enzymol 1955. [DOI: 10.1016/s0076-6879(55)02240-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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BRAWERMAN G, CHARGAFF E. On the synthesis of nucleotides by nucleoside phosphotransferases. BIOCHIMICA ET BIOPHYSICA ACTA 1954; 15:549-59. [PMID: 13230103 DOI: 10.1016/0006-3002(54)90013-x] [Citation(s) in RCA: 57] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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GOLDWASSER E. The enzymic conversion of adenine to adenosine phosphates. BIOCHIMICA ET BIOPHYSICA ACTA 1954; 13:341-6. [PMID: 13140345 DOI: 10.1016/0006-3002(54)90339-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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FRIEDKIN M. Purine and pyrimidine metabolism in microorganisms. JOURNAL OF CELLULAR PHYSIOLOGY. SUPPLEMENT 1953; 41:261-82. [PMID: 13052640 DOI: 10.1002/jcp.1030410416] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Balis ME, Levin DH, Brown GB, Elion GB, Vanderwerff H, Hitchings GH. THE INCORPORATION OF EXOGENOUS PURINES INTO PENTOSE NUCLEIC ACID BY LACTOBACILLUS CASEI. J Biol Chem 1952. [DOI: 10.1016/s0021-9258(19)52404-8] [Citation(s) in RCA: 58] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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