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Updated: Jun 30, 2026

Generation of Marked and Markerless Mutants in Model Cyanobacterial Species
Published on: May 29, 2016
SigF controls carotenoid pigment production and affects transformation efficiency and hydrogen peroxide sensitivity
Roberta Provvedi1, Dana Kocíncová, Valentina Donà
1Dipartimento di Biologia, Universitá di Padova, Padua, Italy.
Abstract:
Carotenoids are complex lipids that are known for acting against photodynamic injury and free radicals. We demonstrate here that sigma(F) is required for carotenoid pigment production in Mycobacterium smegmatis. We further show that a sigF mutant exhibits a transformation efficiency 10(4)-fold higher than that of the parental strain, suggesting that sigma(F) regulates the production of components affecting cell wall permeability. In addition, a sigF mutant showed an increased sensitivity to hydrogen peroxide. An in silico search of the M. smegmatis genome identified a number of SigF consensus sites, including sites upstream of the carotenoid synthesis locus, which explains its SigF regulation.
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