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Schollmeyer J, Waldburger S, Njo K, Yehia H, Kurreck A, Neubauer P, Riedel SL. Bioprocess development to produce a hyperthermostable S-methyl-5'-thioadenosine phosphorylase in Escherichia coli. Biotechnol Bioeng 2023; 120:3322-3334. [PMID: 37574915 DOI: 10.1002/bit.28526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 07/27/2023] [Accepted: 08/03/2023] [Indexed: 08/15/2023]
Abstract
Nucleoside phosphorylases are important biocatalysts for the chemo-enzymatic synthesis of nucleosides and their analogs which are, among others, used for the treatment of viral infections or cancer. S-methyl-5'-thioadenosine phosphorylases (MTAP) are a group of nucleoside phosphorylases and the thermostable MTAP of Aeropyrum pernix (ApMTAP) was described to accept a wide range of modified nucleosides as substrates. Therefore, it is an interesting biocatalyst for the synthesis of nucleoside analogs for industrial and therapeutic applications. To date, thermostable nucleoside phosphorylases were produced in shake flask cultivations using complex media. The drawback of this approach is low volumetric protein yields which hamper the wide-spread application of the thermostable nucleoside phosphorylases in large scale. High cell density (HCD) cultivations allow the production of recombinant proteins with high volumetric yields, as final optical densities >100 can be achieved. Therefore, in this study, we developed a suitable protocol for HCD cultivations of ApMTAP. Initially, optimum expression conditions were determined in 24-well plates using a fed-batch medium. Subsequently, HCD cultivations were performed using E. coli BL21-Gold cells, by employing a glucose-limited fed-batch strategy. Comparing different growth rates in stirred-tank bioreactors, cultivations revealed that growth at maximum growth rates until induction resulted in the highest yields of ApMTAP. On a 500-mL scale, final cell dry weights of 87.1-90.1 g L-1 were observed together with an overproduction of ApMTAP in a 1.9%-3.8% ratio of total protein. Compared to initially applied shake flask cultivations with terrific broth (TB) medium the volumetric yield increased by a factor of 136. After the purification of ApMTAP via heat treatment and affinity chromatography, a purity of more than 90% was determined. Activity testing revealed specific activities in the range of 0.21 ± 0.11 (low growth rate) to 3.99 ± 1.02 U mg-1 (growth at maximum growth rate). Hence, growth at maximum growth rate led to both an increased expression of the target protein and an increased specific enzyme activity. This study paves the way towards the application of thermostable nucleoside phosphorylases in industrial applications due to an improved heterologous expression in Escherichia coli.
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Affiliation(s)
- Julia Schollmeyer
- Technische Universität Berlin, Faculty III Process Sciences, Institute of Biotechnology, Chair of Bioprocess Engineering, Berlin, Germany
- BioNukleo GmbH, Berlin, Germany
| | - Saskia Waldburger
- Technische Universität Berlin, Faculty III Process Sciences, Institute of Biotechnology, Chair of Bioprocess Engineering, Berlin, Germany
| | - Kendra Njo
- Technische Universität Berlin, Faculty III Process Sciences, Institute of Biotechnology, Chair of Bioprocess Engineering, Berlin, Germany
- BioNukleo GmbH, Berlin, Germany
| | - Heba Yehia
- Technische Universität Berlin, Faculty III Process Sciences, Institute of Biotechnology, Chair of Bioprocess Engineering, Berlin, Germany
- Department of Chemistry of Natural and Microbial Products, Pharmaceutical and Drug Industries Research Institute, National Research Centre, Dokki, Cairo, Egypt
| | - Anke Kurreck
- Technische Universität Berlin, Faculty III Process Sciences, Institute of Biotechnology, Chair of Bioprocess Engineering, Berlin, Germany
- BioNukleo GmbH, Berlin, Germany
| | - Peter Neubauer
- Technische Universität Berlin, Faculty III Process Sciences, Institute of Biotechnology, Chair of Bioprocess Engineering, Berlin, Germany
| | - Sebastian L Riedel
- Technische Universität Berlin, Faculty III Process Sciences, Institute of Biotechnology, Chair of Bioprocess Engineering, Berlin, Germany
- Berliner Hochschule für Technik, Department VIII - Mechanical Engineering, Event Technology and Process Engineering, Environmental and Bioprocess Engineering Laboratory, Berlin, Germany
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2
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Dyzma A, Wielgus-Kutrowska B, Girstun A, Matošević ZJ, Staroń K, Bertoša B, Trylska J, Bzowska A. Trimeric Architecture Ensures the Stability and Biological Activity of the Calf Purine Nucleoside Phosphorylase: In Silico and In Vitro Studies of Monomeric and Trimeric Forms of the Enzyme. Int J Mol Sci 2023; 24:ijms24032157. [PMID: 36768477 PMCID: PMC9916683 DOI: 10.3390/ijms24032157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 01/13/2023] [Accepted: 01/16/2023] [Indexed: 01/24/2023] Open
Abstract
Mammalian purine nucleoside phosphorylase (PNP) is biologically active as a homotrimer, in which each monomer catalyzes a reaction independently of the others. To answer the question of why the native PNP forms a trimeric structure, we constructed, in silico and in vitro, the monomeric form of the enzyme. Molecular dynamics simulations showed different geometries of the active site in the non-mutated trimeric and monomeric PNP forms, which suggested that the active site in the isolated monomer could be non-functional. To confirm this hypothesis, six amino acids located at the interface of the subunits were selected and mutated to alanines to disrupt the trimer and obtain a monomer (6Ala PNP). The effects of these mutations on the enzyme structure, stability, conformational dynamics, and activity were examined. The solution experiments confirmed that the 6Ala PNP mutant occurs mainly as a monomer, with a secondary structure almost identical to the wild type, WT PNP, and importantly, it shows no enzymatic activity. Simulations confirmed that, although the secondary structure of the 6Ala monomer is similar to the WT PNP, the positions of the amino acids building the 6Ala PNP active site significantly differ. These data suggest that a trimeric structure is necessary to stabilize the geometry of the active site of this enzyme.
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Affiliation(s)
- Alicja Dyzma
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
| | - Beata Wielgus-Kutrowska
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
- Correspondence: (B.W.-K.); (A.B.)
| | - Agnieszka Girstun
- Department of Molecular Biology, Institute of Biochemistry, Faculty of Biology University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland
| | - Zoe Jelić Matošević
- Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, HR-10000 Zagreb, Croatia
| | - Krzysztof Staroń
- Department of Molecular Biology, Institute of Biochemistry, Faculty of Biology University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland
| | - Branimir Bertoša
- Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, HR-10000 Zagreb, Croatia
| | - Joanna Trylska
- Centre of New Technologies, University of Warsaw, Banacha 2c, 02-097 Warsaw, Poland
| | - Agnieszka Bzowska
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
- Correspondence: (B.W.-K.); (A.B.)
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3
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Holanda RJ, Deves C, Moreira-Dill LS, Guimarães CL, Marttinelli LKB, Fernandes CFC, Medeiros PSM, Pereira SS, Honda ER, Stábeli RG, Santos DS, Soares AM, Pereira da Silva LH. Plasmodium falciparum purine nucleoside phosphorylase as a model in the search for new inhibitors by high throughput screening. Int J Biol Macromol 2020; 165:1832-1841. [PMID: 33075341 DOI: 10.1016/j.ijbiomac.2020.10.062] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 09/28/2020] [Accepted: 10/09/2020] [Indexed: 10/23/2022]
Abstract
Studies have shown that inhibition of Plasmodium falciparum Purine Nucleoside Phosphorylase (PfPNP) blocks the purine salvage pathway in vitro and in vivo. In this study, PfPNP was evaluated as a model in the search for new inhibitors using surface plasmon resonance (SPR). Its expression, purification, oligomeric state, kinetic constants, calorimetric parameters and kinetic mechanisms were obtained. PfPNP was immobilized on a CM5 sensor chip and sensorgrams were produced through binding the enzyme to the substrate MESG and interactions between molecules contained in 10 fractions of natural extracts. The oligomeric state showed that recombinant PfPNP is a hexamer. The true steady-state kinetic parameters for the substrate inosine were: KM 17 μM, kcat 1.2 s-1, VMax 2.2 U/mg and kcat/KM 7 × 10-4; for MESG they were: KM 131 μM, kcat 2.4 s-1, VMax 4.4 U/mg and kcat/KM 1.8 × 10-4. The thermodynamic parameters for the substrate Phosphate were: ΔG - 5.8 cal mol-1, ΔH - 6.5 cal mol-1 and ΔS - 2.25 cal mol-1/degree. The ITC results demonstrated that the binding of phosphate to free PfPNP led to a significant change in heat and association constants and thermodynamic parameters. A sequential ordered mechanism was proposed as the kinetic mechanism. Three plant extracts contained molecules capable of interacting with PfPNP, showing different levels of affinity. The identification of plant extract fractions containing molecules that interact with recombinant PfPNP using SRP validates this target as a model in the search for new inhibitors. In this study, we showed for the first time the true steady-state kinetic parameters for reactions catalyzed by PfPNP and a model using PfPNP as a target for High-throughput Screening for new inhibitors through SPR. This knowledge will allow for the development of more efficient research methods in the search for new drugs against malaria.
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Affiliation(s)
- Rudson J Holanda
- Universidade Federal do Amazonas, UFAM, campus Humaitá, Amazonas, Brazil; Laboratório de Biotecnologia de Proteínas e Compostos Bioativos da Amazônia Ocidental, LABIOPROT, Centro de Estudos de Biomoléculas Aplicadas à Saúde, CEBio, Fundação Oswaldo Cruz, FIOCRUZ, Fiocruz Rondônia e Universidade Federal de Rondônia, UNIR, Porto Velho, Rondônia, Brazil.
| | - Candida Deves
- Centro de Pesquisa em Biologia Molecular e Funcional, PUCRS, Porto Alegre, Rio Grande do Sul, Brazil
| | - Leandro S Moreira-Dill
- Laboratório de Biotecnologia de Proteínas e Compostos Bioativos da Amazônia Ocidental, LABIOPROT, Centro de Estudos de Biomoléculas Aplicadas à Saúde, CEBio, Fundação Oswaldo Cruz, FIOCRUZ, Fiocruz Rondônia e Universidade Federal de Rondônia, UNIR, Porto Velho, Rondônia, Brazil
| | - Cesar L Guimarães
- Laboratório de Biotecnologia de Proteínas e Compostos Bioativos da Amazônia Ocidental, LABIOPROT, Centro de Estudos de Biomoléculas Aplicadas à Saúde, CEBio, Fundação Oswaldo Cruz, FIOCRUZ, Fiocruz Rondônia e Universidade Federal de Rondônia, UNIR, Porto Velho, Rondônia, Brazil
| | - Leonardo K B Marttinelli
- Centro de Pesquisa em Biologia Molecular e Funcional, PUCRS, Porto Alegre, Rio Grande do Sul, Brazil
| | - Carla F C Fernandes
- Laboratório de Biotecnologia de Proteínas e Compostos Bioativos da Amazônia Ocidental, LABIOPROT, Centro de Estudos de Biomoléculas Aplicadas à Saúde, CEBio, Fundação Oswaldo Cruz, FIOCRUZ, Fiocruz Rondônia e Universidade Federal de Rondônia, UNIR, Porto Velho, Rondônia, Brazil; Laboratório de Engenharia de Anticorpos, Fiocruz Rondônia, Porto Velho, Rondônia, Brazil; Fundação Oswaldo Cruz, FIOCRUZ, Fiocruz Ceará, Fortaleza, Ceará, Brazil
| | - Patrícia S M Medeiros
- Laboratório de Biotecnologia de Proteínas e Compostos Bioativos da Amazônia Ocidental, LABIOPROT, Centro de Estudos de Biomoléculas Aplicadas à Saúde, CEBio, Fundação Oswaldo Cruz, FIOCRUZ, Fiocruz Rondônia e Universidade Federal de Rondônia, UNIR, Porto Velho, Rondônia, Brazil
| | - Soraya S Pereira
- Laboratório de Biotecnologia de Proteínas e Compostos Bioativos da Amazônia Ocidental, LABIOPROT, Centro de Estudos de Biomoléculas Aplicadas à Saúde, CEBio, Fundação Oswaldo Cruz, FIOCRUZ, Fiocruz Rondônia e Universidade Federal de Rondônia, UNIR, Porto Velho, Rondônia, Brazil; Laboratório de Engenharia de Anticorpos, Fiocruz Rondônia, Porto Velho, Rondônia, Brazil
| | - Eduardo R Honda
- Instituto de Pesquisa em Patologias Tropicais de Rondônia, IPEPATRO e Laboratório Central, LACEN, Porto Velho, Rondônia, Brazil
| | - Rodrigo G Stábeli
- Laboratório de Biotecnologia de Proteínas e Compostos Bioativos da Amazônia Ocidental, LABIOPROT, Centro de Estudos de Biomoléculas Aplicadas à Saúde, CEBio, Fundação Oswaldo Cruz, FIOCRUZ, Fiocruz Rondônia e Universidade Federal de Rondônia, UNIR, Porto Velho, Rondônia, Brazil; Fundação Oswaldo Cruz, FIOCRUZ, Plataforma Bi-institucional de Medicina Translacional, Ribeirão Preto, São Paulo, Brazil
| | - Diógenes S Santos
- Centro de Pesquisa em Biologia Molecular e Funcional, PUCRS, Porto Alegre, Rio Grande do Sul, Brazil
| | - Andreimar M Soares
- Laboratório de Biotecnologia de Proteínas e Compostos Bioativos da Amazônia Ocidental, LABIOPROT, Centro de Estudos de Biomoléculas Aplicadas à Saúde, CEBio, Fundação Oswaldo Cruz, FIOCRUZ, Fiocruz Rondônia e Universidade Federal de Rondônia, UNIR, Porto Velho, Rondônia, Brazil; Centro Universitário São Lucas, UniSL, Porto Velho, Rondônia, Brazil; Instituto Nacional de Ciência e Tecnologia de Epidemiologia da Amazônia Ocidental, INCT-EpiAmO, Brazil.
| | - Luiz H Pereira da Silva
- Laboratório de Biotecnologia de Proteínas e Compostos Bioativos da Amazônia Ocidental, LABIOPROT, Centro de Estudos de Biomoléculas Aplicadas à Saúde, CEBio, Fundação Oswaldo Cruz, FIOCRUZ, Fiocruz Rondônia e Universidade Federal de Rondônia, UNIR, Porto Velho, Rondônia, Brazil
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Stachelska-Wierzchowska A, Wierzchowski J, Górka M, Bzowska A, Stolarski R, Wielgus-Kutrowska B. Tricyclic Nucleobase Analogs and Their Ribosides as Substrates and Inhibitors of Purine-Nucleoside Phosphorylases III. Aminopurine Derivatives. Molecules 2020; 25:E681. [PMID: 32033464 PMCID: PMC7037862 DOI: 10.3390/molecules25030681] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 01/24/2020] [Accepted: 01/30/2020] [Indexed: 11/16/2022] Open
Abstract
Etheno-derivatives of 2-aminopurine, 2-aminopurine riboside, and 7-deazaadenosine (tubercidine) were prepared and purified using standard methods. 2-Aminopurine reacted with aqueous chloroacetaldehyde to give two products, both exhibiting substrate activity towards bacterial (E. coli) purine-nucleoside phosphorylase (PNP) in the reverse (synthetic) pathway. The major product of the chemical synthesis, identified as 1,N2-etheno-2-aminopurine, reacted slowly, while the second, minor, but highly fluorescent product, reacted rapidly. NMR analysis allowed identification of the minor product as N2,3-etheno-2-aminopurine, and its ribosylation product as N2,3-etheno-2-aminopurine-N2--D-riboside. Ribosylation of 1,N2-etheno-2-aminopurine led to analogous N2--d-riboside of this base. Both enzymatically produced ribosides were readily phosphorolysed by bacterial PNP to the respective bases. The reaction of 2-aminopurine-N9- -D-riboside with chloroacetaldehyde gave one major product, clearly distinct from that obtained from the enzymatic synthesis, which was not a substrate for PNP. A tri-cyclic 7-deazaadenosine (tubercidine) derivative was prepared in an analogous way and shown to be an effective inhibitor of the E. coli, but not of the mammalian enzyme. Fluorescent complexes of amino-purine analogs with E. coli PNP were observed.
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Affiliation(s)
| | - Jacek Wierzchowski
- Department of Physics and Biophysics, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland;
| | - Michał Górka
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, 5 Pasteura St., 02-093 Warsaw, Poland; (M.G.); (A.B.); (R.S.)
- Biological and Chemical Research Centre, University of Warsaw, 101 Zwirki i Wigury St., 02-089 Warsaw, Poland
| | - Agnieszka Bzowska
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, 5 Pasteura St., 02-093 Warsaw, Poland; (M.G.); (A.B.); (R.S.)
| | - Ryszard Stolarski
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, 5 Pasteura St., 02-093 Warsaw, Poland; (M.G.); (A.B.); (R.S.)
| | - Beata Wielgus-Kutrowska
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, 5 Pasteura St., 02-093 Warsaw, Poland; (M.G.); (A.B.); (R.S.)
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5
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Tri-Cyclic Nucleobase Analogs and their Ribosides as Substrates of Purine-Nucleoside Phosphorylases. II Guanine and Isoguanine Derivatives. Molecules 2019; 24:molecules24081493. [PMID: 30995785 PMCID: PMC6514686 DOI: 10.3390/molecules24081493] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 03/27/2019] [Accepted: 04/09/2019] [Indexed: 11/17/2022] Open
Abstract
Etheno-derivatives of guanine, O6-methylguanine, and isoguanine were prepared and purified using standard methods. The title compounds were examined as potential substrates of purine-nucleoside phosphorylases from various sources in the reverse (synthetic) pathway. It was found that 1,N2-etheno-guanine and 1,N6-etheno-isoguanine are excellent substrates for purine-nucleoside phosphorylase (PNP) from E. coli, while O6-methyl-N2,3-etheno-guanine exhibited moderate activity vs. this enzyme. The latter two compounds displayed intense fluorescence in neutral aqueous medium, and so did the corresponding ribosylation products. By contrast, PNP from calf spleens exhibited only modest activity towards 1,N6-etheno-isoguanine; the remaining compounds were not ribosylated by this enzyme. The enzymatic ribosylation of 1,N6-etheno-isoguanine using two forms of calf PNP (wild type and N243D) and E. coli PNP (wild type and D204N) gave three different products, which were identified on the basis of NMR analysis and comparison with the product of the isoguanosine reaction with chloroacetic aldehyde, which gave an essentially single compound, identified unequivocally as N9-riboside. With the wild-type E. coli enzyme as a catalyst, N9--d- and N7--d-ribosides are obtained in proportion ~1:3, while calf PNP produced another riboside, tentatively identified as N6--d-riboside. The potential application of various forms of PNP for synthesis of the tri-cyclic nucleoside analogs is discussed.
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Stachelska-Wierzchowska A, Wierzchowski J, Bzowska A, Wielgus-Kutrowska B. Tricyclic nitrogen base 1,N 6-ethenoadenine and its ribosides as substrates for purine-nucleoside phosphorylases: Spectroscopic and kinetic studies. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2018; 37:89-101. [PMID: 29376769 DOI: 10.1080/15257770.2017.1419255] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The title compound is an excellent substrate for E. coli PNP, as well as for its D204N mutant. The main product of the synthetic reaction is N9-riboside, but some amount of N7-riboside is also present. Surprisingly, 1,N6-ethenoadenine is also ribosylated by both wild-type and mutated (N243D) forms of calf PNP, which catalyze the synthesis of a different riboside, tentatively identified as N6-β-D-ribosyl-1,N6-ethenoadenine. All ribosides are susceptible to phosphorolysis by the E. coli PNP (wild type). All the ribosides are fluorescent and can be utilized as analytical probes.
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Affiliation(s)
| | - Jacek Wierzchowski
- a Department of Biophysics , University of Varmia & Masuria in Olsztyn , 4 Oczapowskiego St, Olsztyn , Poland
| | - Agnieszka Bzowska
- b Division of Biophysics, Institute of Experimental Physics, Faculty of Physics , University of Warsaw , 5 Pasteura St., Warsaw , Poland
| | - Beata Wielgus-Kutrowska
- b Division of Biophysics, Institute of Experimental Physics, Faculty of Physics , University of Warsaw , 5 Pasteura St., Warsaw , Poland
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7
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Stachelska-Wierzchowska A, Wierzchowski J, Bzowska A, Wielgus-Kutrowska B. Site-Selective Ribosylation of Fluorescent Nucleobase Analogs Using Purine-Nucleoside Phosphorylase as a Catalyst: Effects of Point Mutations. Molecules 2015; 21:E44. [PMID: 26729076 PMCID: PMC6274182 DOI: 10.3390/molecules21010044] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Revised: 12/07/2015] [Accepted: 12/09/2015] [Indexed: 01/31/2023] Open
Abstract
Enzymatic ribosylation of fluorescent 8-azapurine derivatives, like 8-azaguanine and 2,6-diamino-8-azapurine, with purine-nucleoside phosphorylase (PNP) as a catalyst, leads to N9, N8, and N7-ribosides. The final proportion of the products may be modulated by point mutations in the enzyme active site. As an example, ribosylation of the latter substrate by wild-type calf PNP gives N7- and N8-ribosides, while the N243D mutant directs the ribosyl substitution at N9- and N7-positions. The same mutant allows synthesis of the fluorescent N7-β-d-ribosyl-8-azaguanine. The mutated form of the E. coli PNP, D204N, can be utilized to obtain non-typical ribosides of 8-azaadenine and 2,6-diamino-8-azapurine as well. The N7- and N8-ribosides of the 8-azapurines can be analytically useful, as illustrated by N7-β-d-ribosyl-2,6-diamino-8-azapurine, which is a good fluorogenic substrate for mammalian forms of PNP, including human blood PNP, while the N8-riboside is selective to the E. coli enzyme.
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Affiliation(s)
- Alicja Stachelska-Wierzchowska
- Department of Physics and Biophysics, University of Varmia & Masuria in Olsztyn, 4 Oczapowskiego St., 10-719 Olsztyn, Poland.
| | - Jacek Wierzchowski
- Department of Physics and Biophysics, University of Varmia & Masuria in Olsztyn, 4 Oczapowskiego St., 10-719 Olsztyn, Poland.
| | - Agnieszka Bzowska
- Division of Biophysics, Institute of Experimental Physics, University of Warsaw, Zwirki i Wigury 93, 02-089 Warsaw, Poland.
| | - Beata Wielgus-Kutrowska
- Division of Biophysics, Institute of Experimental Physics, University of Warsaw, Zwirki i Wigury 93, 02-089 Warsaw, Poland.
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Purine nucleoside phosphorylase activity decline is linked to the decay of the trimeric form of the enzyme. Arch Biochem Biophys 2014; 549:40-8. [DOI: 10.1016/j.abb.2014.03.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 03/17/2014] [Accepted: 03/19/2014] [Indexed: 10/25/2022]
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9
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Wielgus-Kutrowska B, Breer K, Hashimoto M, Hikishima S, Yokomatsu T, Narczyk M, Dyzma A, Girstun A, Staroń K, Bzowska A. Trimeric purine nucleoside phosphorylase: Exploring postulated one-third-of-the-sites binding in the transition state. Bioorg Med Chem 2012; 20:6758-69. [DOI: 10.1016/j.bmc.2012.08.045] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Accepted: 08/24/2012] [Indexed: 11/28/2022]
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10
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Chojnowski G, Breer K, Narczyk M, Wielgus-Kutrowska B, Czapinska H, Hashimoto M, Hikishima S, Yokomatsu T, Bochtler M, Girstun A, Staroń K, Bzowska A. 1.45Å resolution crystal structure of recombinant PNP in complex with a pM multisubstrate analogue inhibitor bearing one feature of the postulated transition state. Biochem Biophys Res Commun 2010; 391:703-8. [DOI: 10.1016/j.bbrc.2009.11.124] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2009] [Accepted: 11/19/2009] [Indexed: 10/20/2022]
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11
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Breer K, Wielgus-Kutrowska B, Girstun A, Staroń K, Hashimoto M, Hikishima S, Yokomatsu T, Bzowska A. Overexpressed proteins may act as mops removing their ligands from the host cells: a case study of calf PNP. Biochem Biophys Res Commun 2009; 391:1203-9. [PMID: 20005207 DOI: 10.1016/j.bbrc.2009.12.037] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2009] [Accepted: 12/08/2009] [Indexed: 10/20/2022]
Abstract
Calf purine nucleoside phosphorylase (PNP) was overexpressed in Escherichia coli. The basic kinetic parameters of recombinant PNP were found to be similar to the values published previously for non-recombinant PNP from calf spleen. However, upon titration of the recombinant enzyme with the tight-binding multisubstrate analogue inhibitor DFPP-DG, endothermic as well as exothermic signals were obtained. This was not the case for PNP isolated from calf spleen for which only the endothermic process was observed. Further calorimetric titrations of the recombinant and non-recombinant enzyme with its potent and moderate ligands, and studied involving partial inactivation of the enzyme, lead to the conclusion that a part of the recombinant enzyme forms a complex with its product, hypoxanthine, although hypoxanthine was not present at any purification stage except for its natural occurrence in E. coli cells. Binding of hypoxanthine is accompanied with a large negative change of the free enthalpy, and therefore the replacement of this compound by DFPP-DG yields positive heat signal. Our data obtained with calf PNP indicate that similar processes--moping of ligands from the host cells--may take place in the case of other proteins with high overexpression yield.
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Affiliation(s)
- Katarzyna Breer
- Department of Biophysics, Institute of Experimental Physics, University of Warsaw, Zwirki i Wigury 93, 02-089 Warsaw, Poland
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