PhyT is a negative regulator of GSR in vivo.

β-galactosidase activity of the EcfG-dependent nhaA2p-lacZ fusion in indicated S. melonis Fr1 mutant backgrounds upon overnight overexpression of phyT from the cumate-inducible pQH vector with 25 μM cumate. Empty pQH vector was used as a negative control. Black bars and gray bars represent β-galactosidase activity pre- and 1 h post-induction with the chemical stress mixture (1% ethanol, 80 mM NaCl and 50 μM TBHP). Values are given as mean ±SD of three independent experiments.