| Texto completo | |
| Autor(es): |
da Silva, Carolina A. P. T.
[1]
;
Lourenco, Rogerio F.
[2]
;
Mazzon, Ricardo R.
[1, 3]
;
Ribeiro, Rodolfo A.
[1]
;
Marques, Marilis V.
[1]
Número total de Autores: 5
|
| Afiliação do(s) autor(es): | [1] Univ Sao Paulo, Inst Ciencias Biomed, Dept Microbiol, Ave Prof Lineu Prestes 1374, BR-05508000 Sao Paulo, SP - Brazil
[2] Univ Sao Paulo, Inst Quim, Dept Bioquim, Ave Prof Lineu Prestes 748, BR-05508000 Sao Paulo, SP - Brazil
[3] Univ Fed Santa Catarina, Ctr Ciencias Biol, Dept Microbiol Imunol & Parasitol, Campus Univ Trindade, Caixa Postal 476, BR-88040900 Florianopolis, SC - Brazil
Número total de Afiliações: 3
|
| Tipo de documento: | Artigo Científico |
| Fonte: | BMC Microbiology; v. 16, APR 12 2016. |
| Citações Web of Science: | 6 |
| Resumo | |
Background: As bacterial cells enter stationary phase, they adjust their growth rate to comply with nutrient restriction and acquire increased resistance to several stresses. These events are regulated by controlling gene expression at this phase, changing the mode of exponential growth into that of growth arrest, and increasing the expression of proteins involved in stress resistance. The two-component system SpdR/SpdS is required for the activation of transcription of the Caulobacter crescentus cspD gene at the onset of stationary phase. Results: In this work, we showed that both SpdR and SpdS are also induced upon entry into stationary phase, and this induction is partly mediated by ppGpp and it is not auto-regulated. Global transcriptional analysis at early stationary phase of a spdR null mutant strain compared to the wild type strain was carried out by DNA microarray. Twenty-three genes showed at least twofold decreased expression in the spdR deletion mutant strain relative to its parental strain, including cspD, while five genes showed increased expression in the mutant. The expression of a set of nine genes was evaluated by quantitative real time PCR, validating the microarray data, and indicating an important role for SpdR at stationary phase. Several of the differentially expressed genes can be involved in modulating gene expression, including four transcriptional regulators, and the RNA regulatory protein Hfq. The ribosomal proteins NusE and NusG, which also have additional regulatory functions in transcription and translation, were also downregulated in the spdR mutant, as well as the ParE1 toxin. The purified SpdR protein was shown to bind to the regulatory region of CC0517 by Electrophoretic Mobility Shift Assay, and the SpdR-regulated gene CC0731 was shown to be expressed at a lower level in the null cspD mutant, suggesting that at least part of the effect of SpdR on the expression of this gene is indirect. Conclusions: The results indicate that SpdR regulates several genes encoding proteins of regulatory function, which in turn may be required for the expression of other genes important for the transition to stationary phase. (AU) | |
| Processo FAPESP: | 14/04046-8 - Sistemas regulatórios da resposta bacteriana a estresses |
| Beneficiário: | Marilis Do Valle Marques |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |
| Processo FAPESP: | 11/18847-4 - Identificação de genes regulados em resposta a carência de zinco em Caulobacter crescentus |
| Beneficiário: | Ricardo Ruiz Mazzon |
| Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |
| Processo FAPESP: | 12/10563-0 - Sistemas regulatórios e fisiológicos da resposta bacteriana a estresses |
| Beneficiário: | Marilis Do Valle Marques |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |
| Processo FAPESP: | 11/17513-5 - Determinação dos genes regulados pelo fator de transcrição SpdR e seu envolvimento na adaptação a fase estacionária em Caulobacter crescentus |
| Beneficiário: | Carolina Antunes Do Prado Tavares da Silva |
| Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |
| Processo FAPESP: | 11/50604-4 - Caracterizacao bioquimica e estrutural das interacoes da proteina rrp43 com outras subunidades do exossomos de levedura. |
| Beneficiário: | Rogério Ferreira Lourenço |
| Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |