Table 1.

Hfq-dependent sRNAs involved in the stress response of E. coli growing in bioreactor

Stressor	RNA	Length	Regulation	Physiological response	References
Temperature	MicC	109	Increased at low temperature	Repression of porin synthesis OmpC	[25]
	MicF	93	Increased at high temperature	Repression of translation and stability of porin OmpF	[26]
	DsrA	87	Increased at low temperature	Activation of translation of rpoS and inhibition of translation of hns	[27–30]
Osmolarity	MicF	93	Induced by high osmolarity	Repression of translation and stability of porin OmpF	[31, 32]
	RprA	105	Induced by high osmolarity	Activation of translation of rpoS	[32–34]
Iron	RyhB	90	Induced by limited iron	Repression of iron enzymes, TCA cycle and respiratory chain	[35, 36]
Oxygen	OxyS	109	Induced by oxidative stress (H2O2); activated by OxyR	Repression of unneeded activities and protection against mutagenesis	[37]
	FnrS	113	Induced under anaerobic conditions; activated by FNR, ArcA and CRP	Repression of genes from anaerobic metabolism and oxidative stress	[38, 39]
Glucose	SgrS	227	Induced by glucose-phosphate or analogs; activated by SgrR	Prevent sugar uptake, reduce accumulated sugar-phosphates by repressing ptsG synthesis	[40, 41]
	CyaR	87	Induced by low glucose; activated by CRP	Repression of porin synthesis, membrane proteins, and synthetase enzymes	[42]
	Spot42	109	Induced by glucose; repressed by CRP	Decrease galactose utilization and non-preferred carbon source metabolism	[43, 44]
pH	GadY	105, 90, 59	Induced by low pH	Activation of acid resistance genes from the GDS	[45, 46]
	RprA	105	Induced by low pH	Activation of translation of rpoS	[47]
	DsrA	87	Increased at low pH	Activation of translation of rpoS	[47, 48]