The molecular structure of Schistosoma mansoni PNP isoform 2 provides insights into the nucleoside selectivity of PNPs

Autor(es):Mostrar menos -

Torini, Juliana Roberta ^[1] ; Romanello, Larissa ^[1] ; Heleno Batista, Fernanda Aparecida ^{[2, 3]} ; Balasco Serrao, Vitor Hugo ^[1] ; Faheem, Muhammad ^{[4, 5]} ; Zeraik, Ana Eliza ^[1] ; Bird, Louise ^[6] ; Nettleship, Joanne ^[6] ; Reddivari, Yamini ^[6] ; Owens, Ray ^[6] ; DeMarco, Ricardo ^[1] ; Borges, Julio Cesar ^[2] ; Brandao-Neto, Jose ^[7] ; Pereira, Humberto D'Muniz ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Fis Sao Carlos, Lab Biol Estrutural, Sao Carlos, SP - Brazil

^[2] Univ Sao Paulo, Inst Quim Sao Carlos, Sao Carlos, SP - Brazil

^[3] Ctr Nacl Pesquisa Energia & Mat, Lab Nacl Biociencias, Campinas, SP - Brazil

^[4] Univ Catolica Brasilia, Programa Pos Grad Ciencias Genom & Biotecnol, Brasilia, DF - Brazil

^[5] Univ Brasilia, Dept Biol Celular, Lab Biofis Mol, Brasilia, DF - Brazil

^[6] Rutherford Appleton Lab, OPPF UK, Res Complex Harwell, Oxford - England

^[7] Harwell Sci & Innovat Campus, Diamond Light Source, Didcot, Oxon - England

• Tipo de documento: Artigo Científico
• Fonte: PLoS One; v. 13, n. 9 SEP 7 2018.
• Citações Web of Science: 2

Resumo

Purine nucleoside phosphorylases (PNPs) play an important role in the blood fluke parasite Schistosoma mansoni as a key enzyme of the purine salvage pathway. Here we present the structural and kinetic characterization of a new PNP isoform from S. mansoni, SmPNP2. Thermofluorescence screening of different ligands suggested cytidine and cytosine are potential ligands. The binding of cytosine and cytidine were confirmed by isothermal titration calorimetry, with a K-D of 27 mu M for cytosine, and a K-M of 76.3 mu M for cytidine. SmPNP2 also displays catalytic activity against inosine and adenosine, making it the first described PNP with robust catalytic activity towards both pyrimidines and purines. Crystal structures of SmPNP2 with different ligands were obtained and comparison of these structures with the previously described S. mansoni PNP (SmPNP1) provided clues for the unique capacity of SmPNP2 to bind pyrimidines. When compared with the structure of SmPNP1, substitutions in the vicinity of SmPNP2 active site alter the architecture of the nucleoside base binding site thus permitting an alternative binding mode for nucleosides, with a 180 degrees rotation from the canonical binding mode. The remarkable plasticity of this binding site enhances our understanding of the correlation between structure and nucleotide selectivity, thus suggesting new ways to analyse PNP activity. (AU)

• Processo FAPESP: 12/14223-9 - Estudos estruturais e cinéticos das enzimas da via de salvação de purina de Schistosoma mansoni
• Beneficiário: Humberto D'Muniz Pereira
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 12/10213-9 - Determinação estrutural e funcional das enzimas Metiltioadenosina Fosforilase, Purina Nucleosídeo Fosforilase isoforma 2 e das enzimas participantes da produção de GTP da via de salvação de purinas em Schistosoma mansoni.
• Beneficiário: Juliana Roberta Torini de Souza Oliveira
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 12/23730-1 - Caracterização das interações macromoleculares das proteínas envolvidas na síntese de selenocisteínas em escherichia coli
• Beneficiário: Vitor Hugo Balasco Serrão
• Modalidade de apoio: Bolsas no Brasil - Doutorado