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Frisch J, Maršić T, Loderer C. A Novel One-Pot Enzyme Cascade for the Biosynthesis of Cladribine Triphosphate. Biomolecules 2021; 11:biom11030346. [PMID: 33668847 PMCID: PMC7996316 DOI: 10.3390/biom11030346] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 02/19/2021] [Accepted: 02/22/2021] [Indexed: 02/06/2023] Open
Abstract
Cladribine triphosphate is the active compound of the anti-cancer and multiple sclerosis drug Mavenclad (cladribine). Biosynthesis of such non-natural deoxyribonucleotides is challenging but important in order to study the pharmaceutical modes of action. In this study, we developed a novel one-pot enzyme cascade for the biosynthesis of cladribine triphosphate, starting with the nucleobase 2Cl-adenine and the generic co-substrate phosphoribosyl pyrophosphate. The cascade is comprised of the three enzymes, namely, adenine phosphoribosyltransferase (APT), polyphosphate kinase (PPK), and ribonucleotide reductase (RNR). APT catalyzes the binding of the nucleobase to the ribose moiety, followed by two consecutive phosphorylation reactions by PPK. The formed nucleoside triphosphate is reduced to the final product 2Cl-deoxyadenonsine triphosphate (cladribine triphosphate) by the RNR. The cascade is feasible, showing comparative product concentrations and yields to existing enzyme cascades for nucleotide biosynthesis. While this study is limited to the biosynthesis of cladribine triphosphate, the design of the cascade offers the potential to extend its application to other important deoxyribonucleotides.
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Affiliation(s)
- Julia Frisch
- Chair for Molecular Biotechnology, Technical University, 01217 Dresden, Germany;
| | - Tin Maršić
- Laboratory for Genome Engineering and Synthetic Biology, Division of Biological Sciences, 4700 King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia;
| | - Christoph Loderer
- Chair for Molecular Biotechnology, Technical University, 01217 Dresden, Germany;
- Correspondence: ; Tel.: +49-351-463-39517
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Del Arco J, Martinez M, Donday M, Clemente-Suarez VJ, Fernández-Lucas J. Cloning, expression and biochemical characterization of xanthine and adenine phosphoribosyltransferases from Thermus thermophilus HB8. BIOCATAL BIOTRANSFOR 2017. [DOI: 10.1080/10242422.2017.1313837] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Jon Del Arco
- Applied Biotechnology Group, Research and Doctoral School, European University of Madrid, Urbanización El Bosque, Madrid, Spain
| | - María Martinez
- Applied Biotechnology Group, Research and Doctoral School, European University of Madrid, Urbanización El Bosque, Madrid, Spain
| | - Manuel Donday
- Applied Biotechnology Group, Research and Doctoral School, European University of Madrid, Urbanización El Bosque, Madrid, Spain
| | - Vicente Javier Clemente-Suarez
- Applied Biotechnology Group, Research and Doctoral School, European University of Madrid, Urbanización El Bosque, Madrid, Spain
| | - Jesús Fernández-Lucas
- Applied Biotechnology Group, Research and Doctoral School, European University of Madrid, Urbanización El Bosque, Madrid, Spain
- Grupo de Investigación en Desarrollo Agroindustrial Sostenible, Ingenieróa Agroindustrial, Universidad de la Costa, CUC, Barranquilla, Colombia
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Ceschin J, Hürlimann HC, Saint-Marc C, Albrecht D, Violo T, Moenner M, Daignan-Fornier B, Pinson B. Disruption of Nucleotide Homeostasis by the Antiproliferative Drug 5-Aminoimidazole-4-carboxamide-1-β-d-ribofuranoside Monophosphate (AICAR). J Biol Chem 2015; 290:23947-59. [PMID: 26283791 DOI: 10.1074/jbc.m115.656017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Indexed: 11/06/2022] Open
Abstract
5-Aminoimidazole-4-carboxamide-1-β-D-ribofuranoside monophosphate (AICAR) is a natural metabolite with potent anti-proliferative and low energy mimetic properties. At high concentration, AICAR is toxic for yeast and mammalian cells, but the molecular basis of this toxicity is poorly understood. Here, we report the identification of yeast purine salvage pathway mutants that are synthetically lethal with AICAR accumulation. Genetic suppression revealed that this synthetic lethality is in part due to low expression of adenine phosphoribosyl transferase under high AICAR conditions. In addition, metabolite profiling points to the AICAR/NTP balance as crucial for optimal utilization of glucose as a carbon source. Indeed, we found that AICAR toxicity in yeast and human cells is alleviated when glucose is replaced by an alternative carbon source. Together, our metabolic analyses unveil the AICAR/NTP balance as a major factor of AICAR antiproliferative effects.
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Affiliation(s)
- Johanna Ceschin
- From the Université de Bordeaux and the Centre National de la Recherche Scientifique, Institut de Biochimie et Génétique Cellulaires UMR 5095, Saint-Saëns, F-33077 Bordeaux, France
| | - Hans Caspar Hürlimann
- From the Université de Bordeaux and the Centre National de la Recherche Scientifique, Institut de Biochimie et Génétique Cellulaires UMR 5095, Saint-Saëns, F-33077 Bordeaux, France
| | - Christelle Saint-Marc
- From the Université de Bordeaux and the Centre National de la Recherche Scientifique, Institut de Biochimie et Génétique Cellulaires UMR 5095, Saint-Saëns, F-33077 Bordeaux, France
| | - Delphine Albrecht
- From the Université de Bordeaux and the Centre National de la Recherche Scientifique, Institut de Biochimie et Génétique Cellulaires UMR 5095, Saint-Saëns, F-33077 Bordeaux, France
| | - Typhaine Violo
- From the Université de Bordeaux and the Centre National de la Recherche Scientifique, Institut de Biochimie et Génétique Cellulaires UMR 5095, Saint-Saëns, F-33077 Bordeaux, France
| | - Michel Moenner
- From the Université de Bordeaux and the Centre National de la Recherche Scientifique, Institut de Biochimie et Génétique Cellulaires UMR 5095, Saint-Saëns, F-33077 Bordeaux, France
| | - Bertrand Daignan-Fornier
- From the Université de Bordeaux and the Centre National de la Recherche Scientifique, Institut de Biochimie et Génétique Cellulaires UMR 5095, Saint-Saëns, F-33077 Bordeaux, France
| | - Benoît Pinson
- From the Université de Bordeaux and the Centre National de la Recherche Scientifique, Institut de Biochimie et Génétique Cellulaires UMR 5095, Saint-Saëns, F-33077 Bordeaux, France
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Young GH, Lin JT, Cheng YF, Huang CF, Chao CY, Nong JY, Chen PK, Chen HM. Identification of adenine modulating AMPK activation in NIH/3T3 cells by proteomic approach. J Proteomics 2015; 120:204-14. [DOI: 10.1016/j.jprot.2015.03.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Revised: 02/28/2015] [Accepted: 03/12/2015] [Indexed: 02/08/2023]
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Akizu N, Cantagrel V, Schroth J, Cai N, Vaux K, McCloskey D, Naviaux RK, Van Vleet J, Fenstermaker AG, Silhavy JL, Scheliga JS, Toyama K, Morisaki H, Sonmez FM, Celep F, Oraby A, Zaki MS, Al-Baradie R, Faqeih EA, Saleh MAM, Spencer E, Rosti RO, Scott E, Nickerson E, Gabriel S, Morisaki T, Holmes EW, Gleeson JG. AMPD2 regulates GTP synthesis and is mutated in a potentially treatable neurodegenerative brainstem disorder. Cell 2013; 154:505-17. [PMID: 23911318 DOI: 10.1016/j.cell.2013.07.005] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Revised: 05/10/2013] [Accepted: 07/01/2013] [Indexed: 01/03/2023]
Abstract
Purine biosynthesis and metabolism, conserved in all living organisms, is essential for cellular energy homeostasis and nucleic acid synthesis. The de novo synthesis of purine precursors is under tight negative feedback regulation mediated by adenosine and guanine nucleotides. We describe a distinct early-onset neurodegenerative condition resulting from mutations in the adenosine monophosphate deaminase 2 gene (AMPD2). Patients have characteristic brain imaging features of pontocerebellar hypoplasia (PCH) due to loss of brainstem and cerebellar parenchyma. We found that AMPD2 plays an evolutionary conserved role in the maintenance of cellular guanine nucleotide pools by regulating the feedback inhibition of adenosine derivatives on de novo purine synthesis. AMPD2 deficiency results in defective GTP-dependent initiation of protein translation, which can be rescued by administration of purine precursors. These data suggest AMPD2-related PCH as a potentially treatable early-onset neurodegenerative disease.
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Affiliation(s)
- Naiara Akizu
- Neurogenetics Laboratory, Institute for Genomic Medicine, Rady Children's Hospital, Howard Hughes Medical Institute, University of California, San Diego, La Jolla, CA 92093, USA
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Blundell RD, Williams SJ, Morrow CA, Ericsson DJ, Kobe B, Fraser JA. Purification, crystallization and preliminary X-ray analysis of adenylosuccinate synthetase from the fungal pathogen Cryptococcus neoformans. Acta Crystallogr Sect F Struct Biol Cryst Commun 2013; 69:1033-6. [PMID: 23989157 PMCID: PMC3758157 DOI: 10.1107/s1744309113021921] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Accepted: 08/06/2013] [Indexed: 03/16/2023]
Abstract
With increasingly large immunocompromised populations around the world, opportunistic fungal pathogens such as Cryptococcus neoformans are a growing cause of morbidity and mortality. To combat the paucity of antifungal compounds, new drug targets must be investigated. Adenylosuccinate synthetase is a crucial enzyme in the ATP de novo biosynthetic pathway, catalyzing the formation of adenylosuccinate from inosine monophosphate and aspartate. Although the enzyme is ubiquitous and well characterized in other kingdoms, no crystallographic studies on the fungal protein have been performed. Presented here are the expression, purification, crystallization and initial crystallographic analyses of cryptococcal adenylosuccinate synthetase. The crystals had the symmetry of space group P2(1)2(1)2(1) and diffracted to 2.2 Å resolution.
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Affiliation(s)
- Ross D. Blundell
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Simon J. Williams
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Carl A. Morrow
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Daniel J. Ericsson
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Bostjan Kobe
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia
| | - James A. Fraser
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
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Barrett C, Alley J, Pulido JC, Spurling H, Li P, Parsons T, Mallender WD, Bembenek ME. Configuration of a scintillation proximity assay for the activity assessment of recombinant human adenine phosphoribosyltransferase. Assay Drug Dev Technol 2007; 4:661-9. [PMID: 17199504 DOI: 10.1089/adt.2006.4.661] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Adenine phosphoribosyltransferase plays a role in purine salvage by catalyzing the direct conversion of adenine to adenosine monophosphate. The involvement of the purine salvage pathway in tumor proliferation and angiogenesis makes adenine phosphoribosyltransferase a potential target for oncology drug discovery. We have expressed and characterized recombinant, N-terminally His-tagged human adenine phosphoribosyltransferase. Two assay formats were assessed for use in a high throughput screen: a spectrophotometric-based enzyme-coupled assay system and a radiometric ionic capture scintillation proximity bead assay format. Ultimately, the scintillation proximity assay format was chosen because of automated screening compatibility limitations of the coupled assay. We describe here the biochemical characterization of adenine phosphoribosyltransferase and the development of a robust, homogeneous, 384-well assay suitable for high throughput screening.
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Affiliation(s)
- Cynthia Barrett
- Discovery Technologies, Millennium Pharmaceuticals, Inc., Cambridge, MA 02139, USA.
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Crespillo J, Llorente P, Argomániz L, Montero C. APRT from erythrocytes of HGPRT deficient patients: kinetic, regulatory and thermostability properties. Mol Cell Biochem 2004; 254:359-63. [PMID: 14674717 DOI: 10.1023/a:1027323521969] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Adenine phosphoribosyltransferase (APRT) has been 1200-fold purified from erythrocytes of a patient with partial hipoxanthine-guanine phosphoribosyltransferase (HGPRT) deficiency, Propositus, and in those of a controlHPRT+, with 20% efficiency in both proteins and specific activity of 550 and 243 nmol/h/mgprotein. The specific activity determined in the Propositus enzyme was, in all purification steps, higher than that of the controlHPRT+. Significant changes were found in their thermal stabilities. Half inactivation times at each temperature studied are greater for the Propositus enzyme in the temperature interval 60-80 degrees C. No significant difference has been observed in the affinity constants for adenine and PRPP substrates. Studies on inhibition by the reaction product suggest that AMP is a competitive inhibitor with respect to PRPP in both enzymes, with Ki values of 150 microM in Propositus and 220 microM in controlHPRT+.
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Abstract
The bacterial enzyme S-adenosylmethionine:tRNA ribosyltransferase-isomerase (QueA) catalyzes the unprecedented transfer and isomerization of the ribosyl moiety of S-adenosylmethionine (AdoMet) to a modified tRNA nucleoside in the biosynthesis of the hypermodified nucleoside queuosine. The complexity of this reaction makes it a compelling problem in fundamental mechanistic enzymology, and as part of our mechanistic studies of the QueA-catalyzed reaction, we report here the elucidation of the steady-state kinetic mechanism. Bi-substrate kinetic analysis gave initial velocity patterns indicating a sequential mechanism, and provided the following kinetic constants: K (M)(tRNA)= 1.9 +/- 0.7 microM and K (M)(AdoMet)= 98 +/- 5.0 microM. Dead-end inhibition studies with the substrate analogues S-adenosylhomocysteine and sinefungin gave competitive inhibition patterns against AdoMet and noncompetitive patterns against preQ(1)-tRNA(Tyr), with K(i) values of 133 +/- 18 and 4.6 +/- 0.5 microM for sinefungin and S-adenosylhomocysteine, respectively. Product inhibition by adenine was noncompetitive against both substrates under conditions with a subsaturating cosubstrate concentration and uncompetitive against preQ(1)-tRNA(Tyr) when AdoMet was saturating. Inhibition by the tRNA product (oQ-tRNA(Tyr)) was competitive and noncompetitive against the substrates preQ(1)-tRNA(Tyr) and AdoMet, respectively. Inhibition by methionine was uncompetitive versus preQ(1)-tRNA(Tyr), but noncompetitive against AdoMet. However, when methionine inhibition was investigated at high AdoMet concentrations, the pattern was uncompetitive. Taken together, the data are consistent with a fully ordered sequential bi-ter kinetic mechanism in which preQ(1)-tRNA(Tyr) binds first followed by AdoMet, with product release in the order adenine, methionine, and oQ-tRNA. The chemical mechanism that we previously proposed for the QueA-catalyzed reaction [Daoud Kinzie, S., Thern, B., and Iwata-Reuyl, D. (2000) Org. Lett. 2, 1307-1310] is consistent with the constraints imposed by the kinetic mechanism determined here, and we suggest that the magnitude of the inhibition constants for the dead-end inhibitors may provide insight into the catalytic strategy employed by the enzyme.
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Affiliation(s)
- Steven G Van Lanen
- Department of Chemistry, Portland State University, Portland, Oregon 97207-0751, USA
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Van Lanen SG, Kinzie SD, Matthieu S, Link T, Culp J, Iwata-Reuyl D. tRNA modification by S-adenosylmethionine:tRNA ribosyltransferase-isomerase. Assay development and characterization of the recombinant enzyme. J Biol Chem 2003; 278:10491-9. [PMID: 12533518 DOI: 10.1074/jbc.m207727200] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The enzyme S-adenosylmethionine:tRNA ribosyltransferase-isomerase catalyzes the penultimate step in the biosynthesis of the hypermodified tRNA nucleoside queuosine (Q), an unprecedented ribosyl transfer from the cofactor S-adenosylmethionine (AdoMet) to a modified-tRNA precursor to generate epoxyqueuosine (oQ). The complexity of the reaction makes it an especially interesting mechanistic problem, and as a foundation for detailed kinetic and mechanistic studies we have carried out the basic characterization of the enzyme. Importantly, to allow for the direct measurement of oQ formation, we have developed protocols for the preparation of homogeneous substrates; specifically, an overexpression system was constructed for tRNA(Tyr) in an E. coli queA deletion mutant to allow for the isolation of large quantities of substrate tRNA, and [U-ribosyl-(14)C]AdoMet was synthesized. The enzyme shows optimal activity at pH 8.7 in buffers containing various oxyanions, including acetate, carbonate, EDTA, and phosphate. Unexpectedly, the enzyme was inhibited by Mg(2+) and Mn(2+) in millimolar concentrations. The steady-state kinetic parameters were determined to be K(m)(AdoMet) = 101.4 microm, K(m)(tRNA) = 1.5 microm, and k(cat) = 2.5 min(-1). A short minihelix RNA was synthesized and modified with the precursor 7-aminomethyl-7-deazaguanine, and this served as an efficient substrate for the enzyme (K(m)(RNA) = 37.7 microm and k(cat) = 14.7 min(-1)), demonstrating that the anticodon stem-loop is sufficient for recognition and catalysis by QueA.
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Abstract
Adenine phosphoribosyltransferase (APRT, EC 2.4.2.7) catalyzes the reversible phosphoribosylation of adenine from alpha-D-5-phosphoribosyl-1-pyrophosphate (PRPP) to form AMP and PP(i). Three-dimensional structures of the dimeric APRT enzyme from Leishmania donovani (LdAPRT) bear many similarities to other members of the type 1 phosphoribosyltransferase family but do not reveal the structural basis for catalysis (Phillips, C. L., Ullman, B., Brennan, R. G., and Hill, C. P. (1999) EMBO J. 18, 3533-3545). To address this issue, a steady state and transient kinetic analysis of the enzyme was performed in order to determine the catalytic mechanism. Initial velocity and product inhibition studies indicated that LdAPRT follows an ordered sequential mechanism in which PRPP is the first substrate to bind and AMP is the last product to leave. This mechanistic model was substantiated by equilibrium isotope exchange and fluorescence binding studies, which provided dissociation constants for the LdAPRT-PRPP and LdAPRT-AMP binary complexes. Pre-steady-state kinetic analysis of the forward reaction revealed a burst in product formation indicating that phosphoribosyl transfer proceeds rapidly relative to some rate-limiting product release event. Transient fluorescence competition experiments enabled measurement of rates of binary complex dissociation that implicated AMP release as rate-limiting for the forward reaction. Kinetics of product ternary complex formation were evaluated using the fluorophore formycin AMP and established rate constants for pyrophosphate binding to the LdAPRT-formycin AMP complex. Taken together, these data enabled the complete formulation of an ordered bi-bi kinetic mechanism for LdAPRT in which all of the rate constants were either measured or calculated.
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Affiliation(s)
- Caleb Bashor
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97201-3098, USA
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Alfonzo JD, Crother TR, Guetsova ML, Daignan-Fornier B, Taylor MW. APT1, but not APT2, codes for a functional adenine phosphoribosyltransferase in Saccharomyces cerevisiae. J Bacteriol 1999; 181:347-52. [PMID: 9864350 PMCID: PMC103569 DOI: 10.1128/jb.181.1.347-352.1999] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/1998] [Accepted: 10/21/1998] [Indexed: 11/20/2022] Open
Abstract
The yeast Saccharomyces cerevisiae has two separate genes (APT1 and APT2) that encode two potentially different forms of adenine phosphoribosyltransferase (APRT). However, genetic analysis indicated that only APT1 could code for a complementing activity. Cloning and expression of both the APT1 and APT2 genes in Escherichia coli showed that although discrete proteins (APRT1 and APRT2) were made by these genes, only APRT1 had detectable APRT activity. Northern and Western blot analyses demonstrated that only APT1 was transcribed and translated under normal physiological conditions in yeast. Phylogenetic analysis revealed that APRT1 and APRT2 are evolutionary closely related and that they arise from a gene duplication event. We conclude that APT1 is the functional gene in S. cerevisiae and that APT2 is a pseudogene.
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Affiliation(s)
- J D Alfonzo
- Department of Biology, Indiana University, Bloomington, Indiana 47405, USA
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