4.4.1.28	2-mercaptoethanol	0.5 mM, enhances activity	34507	
4.4.1.28	dithiothreitol	the air-inactivated enzyme is activated by reaction with Fe2+ and dithiothreitol in the absence of air	726942	
4.4.1.28	methyl viologen	4 mM, 40% stimulation	726942	
4.4.1.28	NH4Cl	levels of ammonium content and total enzyme activity are increased in a dose-dependent manner after NH4Cl treatment	748920