Assembly stoichiometry of bacterial selenocysteine synthase and SelC (tRNA(sec))

Autor(es)

Manzine, Livia Regina ^[1] ; Balasco Serrao, Vitor Hugo ^[1] ; Trambaioli da Rocha e Lima, Luis Mauricio ^{[2, 3]} ; de Souza, Marcos Michel ^[1] ; Bettini, Jefferson ^[4] ; Portugal, Rodrigo Villares ^[4] ; van Heel, Marin ^{[5, 6]} ; Thiemann, Otavio Henrique ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Phys Sao Carlos, Dept Phys & Informat, BR-13560970 Sao Carlos, SP - Brazil

^[2] Brazilian Natl Inst Metrol Qual & Technol INMETRO, Lab Biotechnol LaBio DIPRO, Rio De Janeiro - Brazil

^[3] Univ Fed Rio de Janeiro, Natl Inst Sci & Technol Struct Biol & Bioimaging, BR-21941590 Rio De Janeiro - Brazil

^[4] Ctr Nacl Pesquisa Energia Mat CNPEM, Brazilian Nanotechnol Natl Lab LNNano, BR-13083970 Campinas, SP - Brazil

^[5] Univ London Imperial Coll Sci Technol & Med, London SW7 2AZ - England

^[6] Leiden Univ, Gorlaeus Labs, Leiden Inst Chem, NL-9502 Leiden - Netherlands

• Tipo de documento: Artigo Científico
• Fonte: FEBS Letters; v. 587, n. 7, p. 906-911, APR 2 2013.
• Citações Web of Science: 4

Resumo

In bacteria selenocysteyl-tRNA(sec) (SelC) is synthesized by selenocysteine synthase (SelA). Here we show by fluorescence anisotropy binding assays and electron microscopical symmetry analysis that the SelA-tRNA(sec) binding stoichiometry is of one tRNA(sec) molecule per SelA monomer (1: 1) rather than the 1: 2 value proposed previously. Negative stain transmission electron microscopy revealed a D5 pointgroup symmetry for the SelA-tRNA(sec) assembly both with and without tRNA(sec) bound. Furthermore, SelA can associate forming a supramolecular complex of stacked decamer rings, which does not occur in the presence of tRNA(sec). We discuss the structure-function relationships of these assemblies and their regulatory role in bacterial selenocysteyl-tRNA(sec) synthesis. (C) 2013 Published by Elsevier B. V. on behalf of the Federation of European Biochemical Societies. (AU)

• Processo FAPESP: 06/53904-0 - Identificação de elementos estruturais no tRNASecUCA determinantes da ligação com proteínas
• Beneficiário: Livia Regina Manzine Margarido
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 98/14138-2 - Center for Structural Molecular Biotechnology
• Beneficiário: Glaucius Oliva
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs