The alternative sigma factor SigF is a key player in the control of secretion mechanisms in Synechocystis sp. PCC 6803

• Type: Article in International Scientific Journal
• Date: 2019

Authors

Flores, C (Author) Other; Santos, M (Author) Other; Pereira, SB (Author) Other; Mota, R (Author) Other; Rossi, F (Author) Other; De Philippis, R (Author) Other; Couto, N (Author) Other; Karunakaran, E (Author) Other; Wright, PC (Author) Other; Oliveira, P (Author) Other; Paula Tamagnini (Author) FCUP

Journal

Title: Environmental Microbiology

Vol. 21

Pages: 343-359

ISSN: 1462-2912

Publisher: Wiley-Blackwell

Indexing

ISI Web of Knowledge - 20 Citations

Scopus - 24 Citations

Other information

Authenticus ID: P-00Q-040

DOI: 10.1111/1462-2920.14465

Abstract (EN): 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 Delta sigF growth was significantly impaired, the production of released polysaccharides (RPS) increased threefold to fourfold compared with the wild-type. Delta sigF 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 Delta sigF 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 Delta sigF. 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.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 17