Open AccessSucrose favors Pseudomonas aeruginosa pellicle production through the extracytoplasmic function sigma factor SigX
Author(s) -
Bouffartigues Emeline,
Duchesne Rachel,
Bazire Alexis,
Simon Marjolaine,
Maillot Olivier,
Dufour Alain,
Feuilloley Marc,
Orange Nicole,
Chevalier Sylvie
Publication year - 2014
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/1574-6968.12482
Subject(s) - sucrose , sigma factor , chemistry , pseudomonas aeruginosa , osmotic concentration , biochemistry , maltose , strain (injury) , biofilm , microbiology and biotechnology , biology , food science , bacteria , gene expression , gene , promoter , genetics , anatomy
Pseudomonas aeruginosa biofilm formation was increased by addition of sucrose to Luria–Bertani medium, whereas addition of NaCl to a final similar osmolarity and use of maltose instead of sucrose, were ineffective. In a previous study, we showed that the extracytoplasmic sigma factor SigX is activated in the presence of sucrose. The sucrose‐mediated pellicle increase was abolished in a sigX mutant strain. Sucrose addition led to an increase in pel expression and cyclic‐diguanylate (c‐di‐GMP) pool level production. Interestingly, these two phenotypes were strongly decreased in a sigX mutant. Since pel is not known as a SigX‐target, we suspect SigX to be involved in the c‐di‐GMP production. We found that expression of the diguanylate cyclase PA4843 gene was increased in the presence of sucrose at least partly through SigX activity. Our study shows that sucrose itself rather than osmolarity favours the biofilm mode of P. aeruginosa through the activation of SigX.