Multiple signals modulate the activity of the complex sensor kinase TodS.
Bottom Line: In the presence of toluene, menadione reduced TodS activity whereas toluene did not stimulate activity in the presence of menadione.The opposing effects of menadione on glucose and toluene metabolism may be partially responsible for the interwoven regulation of both catabolic pathways.This work provides mechanistic detail on how complex sensor kinases integrate different types of signal molecules.
Affiliation: Department of Environmental Protection, Consejo Superior de Investigaciones Científicas, Estación Experimental del Zaidín, C/ Prof. Albareda 1, Granada, 18008, Spain.Show MeSH
Related in: MedlinePlus
Mentions: Subsequent experiments were aimed at determining the role of cysteine residues in the menadione-mediated inhibition. TodS was treated with 1 mM N-ethylmaleimide (NEM), a reagent that modifies sulfhydryl groups with high specificity (Smyth et al., 1964; Paulech et al., 2013). Whereas NEM-untreated protein showed the expected menadione-dependent reduction in autophosphorylation (Fig. 6A), NEM-treated protein was inactive in the absence and presence of menadione, suggesting that cysteines play a central role in TodS activity.
Affiliation: Department of Environmental Protection, Consejo Superior de Investigaciones Científicas, Estación Experimental del Zaidín, C/ Prof. Albareda 1, Granada, 18008, Spain.