The alternative sigma factor SigF is a key player in the control of secretion mechanisms in Synechocystis sp. PCC 6803.
Environ Microbiol
; 21(1): 343-359, 2019 01.
Article
em En
| MEDLINE
| ID: mdl-30394639
ABSTRACT
Cyanobacterial alternative sigma factors are crucial players in environmental adaptation processes, which may involve bacterial responses related to maintenance of cell envelope and control of secretion pathways. Here, we show that the Group 3 alternative sigma factor F (SigF) plays a pleiotropic role in Synechocystis sp. PCC 6803 physiology, with a major impact on growth and secretion mechanisms, such as the production of extracellular polysaccharides, vesiculation and protein secretion. Although ΔsigF growth was significantly impaired, the production of released polysaccharides (RPS) increased threefold to fourfold compared with the wild-type. ΔsigF exhibits also impairment in formation of outer-membrane vesicles (OMVs) and pili, as well as several other cell envelope alterations. Similarly, the exoproteome composition of ΔsigF differs from the wild-type both in amount and type of proteins identified. Quantitative proteomics (iTRAQ) and an in silico analysis of SigF binding motifs revealed possible targets/pathways under SigF control. Besides changes in protein levels involved in secretion mechanisms, our results indicated that photosynthesis, central carbon metabolism and protein folding/degradation mechanisms are altered in ΔsigF. Overall, this work provided new evidences about the role of SigF on Synechocystis physiology and associates this regulatory element with classical and non-classical secretion pathways.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fator sigma
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Proteínas de Bactérias
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Fímbrias Bacterianas
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Vesículas Secretórias
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Synechocystis
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Environ Microbiol
Assunto da revista:
MICROBIOLOGIA
/
SAUDE AMBIENTAL
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Portugal