6.3.1.8	2 glutathione + spermidine + 2 ATP	trypanothione synthase overall reaction	Crithidia fasciculata	N1,N8-bis(glutathionyl)spermidine + 2 ADP + 2 phosphate	-	?	378685	
6.3.1.8	gamma-Glu-Gly-Gly + spermidine + ATP	at 14% of the activity with gamma-L-Glu-L-Cys-Gly	Crithidia fasciculata	N1-(gamma-Glu-Gly-Gly)-spermidine + ADP + phosphate	-	?	389	
6.3.1.8	gamma-Glu-L-Cys(S-butyl)-Gly + spermidine + ATP	at 24% of the activity with gamma-L-Glu-L-Cys-Gly	Crithidia fasciculata	N1-(gamma-Glu-L-Cys(S-butyl)-Gly)-spermidine + ADP + phosphate	-	?	387	
6.3.1.8	gamma-Glu-L-Cys(S-ethyl)-Gly + spermidine + ATP	at 77% of the activity with gamma-L-Glu-L-Cys-Gly	Crithidia fasciculata	N1-(gamma-Glu-L-Cys(S-ethyl)-Gly)-spermidine + ADP + phosphate	-	?	385	
6.3.1.8	gamma-Glu-L-Cys(S-propyl)-Gly + spermidine + ATP	at 56% of the activity with gamma-L-Glu-L-Cys-Gly	Crithidia fasciculata	N1-(gamma-Glu-L-Cys(S-propyl)-Gly)-spermidine + ADP + phosphate	-	?	386	
6.3.1.8	gamma-Glu-L-Ser-Gly + spermidine + ATP	at 16% of the activity with gamma-L-Glu-L-Cys-Gly	Crithidia fasciculata	N1-(gamma-Glu-L-Ser-Gly)-spermidine + ADP + phosphate	-	?	388	
6.3.1.8	gamma-L-Glu-L-Ala-Gly + spermidine + ATP	at 28% of the activity with gamma-L-Glu-L-Cys-Gly	Crithidia fasciculata	N1-(gamma-L-Glu-L-Ala-Gly)-spermidine + ADP + phosphate	-	?	390	
6.3.1.8	gamma-L-Glu-L-alpha-aminobutyryl-Gly + spermidine + ATP	gamma-L-Glu-L-alpha-aminobutyryl-Gly i.e. ophthalmic acid	Crithidia fasciculata	N1-(gamma-L-Glu-L-alpha-aminobutyryl-Gly)-spermidine	-	?	393	
6.3.1.8	gamma-L-Glu-L-Cys(S-methyl)-Gly + spermidine + ATP	at 74% of the activity with gamma-L-Glu-L-Cys-Gly	Crithidia fasciculata	N1-(gamma-L-Glu-L-Cys(S-methyl)-Gly)-spermidine + ADP + phosphate	-	?	384	
6.3.1.8	gamma-L-Glu-L-Cys-Gly + spermidine + ATP	-	Escherichia coli	N1-(gamma-L-Glu-L-Cys-Gly)-spermidine + ADP + phosphate	-	?	383	
6.3.1.8	gamma-L-Glu-L-Cys-Gly + spermidine + ATP	-	Crithidia fasciculata	N1-(gamma-L-Glu-L-Cys-Gly)-spermidine + ADP + phosphate	-	?	383	
6.3.1.8	gamma-L-Glu-L-Cys-Gly + spermidine + MgATP2-	-	Crithidia fasciculata	N1-(gamma-L-Glu-L-Cys-Gly)-spermidine + MgADP- + phosphate	-	?	369024	
6.3.1.8	gamma-L-Glu-L-Cys-Gly + spermidine + MgATP2-	substitution of the glycine part abolishes activity	Crithidia fasciculata	N1-(gamma-L-Glu-L-Cys-Gly)-spermidine + MgADP- + phosphate	-	?	369024	
6.3.1.8	gamma-L-Glu-L-Ile-Gly + spermidine + ATP	at 70% of the activity with gamma-L-Glu-L-Cys-Gly	Crithidia fasciculata	N1-(gamma-L-Glu-L-Ile-Gly)-spermidine + ADP + phosphate	-	?	392	
6.3.1.8	gamma-L-Glu-L-Val-Gly + spermidine + ATP	at 88% of the activity with gamma-L-Glu-L-Cys-Gly	Crithidia fasciculata	N1-(gamma-L-Glu-L-Val-Gly)-spermidine + ADP + phosphate	-	?	391	
6.3.1.8	gamma-L-Glutamyl-L-cysteinyl-glycine + spermidine + ATP	synthesis of trypanothione, which is involved in maintaining intracellular thiol redox and in defense against oxidants	Crithidia fasciculata	?	-	?	369299	
6.3.1.8	gamma-L-Glutamyl-L-cysteinyl-glycine + spermidine + ATP	key enzyme that participates in the first of two similar steps of trypanothione biosynthesis	Escherichia coli	?	-	?	369299	
6.3.1.8	gamma-L-Glutamyl-L-cysteinyl-glycine + spermidine + ATP	the enzyme is involved in the biosynthesis of the trypanosomatid-specific dithiol trypanothione	Crithidia fasciculata	?	-	?	369299	
6.3.1.8	glutathione + spermidine + ATP	-	Crithidia fasciculata	glutathionylspermidine + ADP + phosphate	-	?	378684	
6.3.1.8	glutathione + spermidine + ATP	-	Escherichia coli	glutathionylspermidine + ADP + phosphate	-	?	378684	
6.3.1.8	glutathione + spermidine + ATP	-	Leishmania infantum	glutathionylspermidine + ADP + phosphate	-	?	378684	
6.3.1.8	glutathione + spermidine + ATP	trypanothione synthase	Crithidia fasciculata	glutathionylspermidine + ADP + phosphate	-	?	378684	
6.3.1.8	glutathione + spermidine + ATP	trypanothione synthase catalyzes both the reaction of glutathionylspermidine synthase, EC 6.3.1.8, and of trypanothione synthase, EC 6.3.1.9, in Trypanosoma brucei	Trypanosoma brucei	glutathionylspermidine + ADP + phosphate	-	?	378684	
6.3.1.8	glutathione + spermidine + ATP	specific for, the enzyme is distinct from the trypanothione synthase, which also catalyzes the reaction but converts glutathionylsperimidine further to trypanothione	Crithidia fasciculata	glutathionylspermidine + ADP + phosphate	-	?	378684	
6.3.1.8	glutathione + spermidine + ATP	glutathionylspermidine is an intermediate formed in the biosynthesis of trypanothione, an essential metabolite in defence against chemical and oxidative stress in the kinetoplastida	Crithidia fasciculata	glutathionylspermidine + ADP + phosphate	-	?	378684	
6.3.1.8	glutathione + spermidine + ATP	-	Leishmania infantum MHOM / MA / 67 / ITMAP263	glutathionylspermidine + ADP + phosphate	-	?	378684	
6.3.1.8	glutathionylspermidine + H2O	amidase activity	Crithidia fasciculata	glutathione + spermidine	-	?	17772	
6.3.1.8	additional information	important reaction in defense against chemical and oxidant stress, thiol redox homeostasis, ribonucleotide metabolism, and drug resistance in parasitic kinetoplastids	Trypanosoma brucei	?	-	?	89	
6.3.1.8	additional information	the enzyme is important for several functions, e.g. for detoxification of H2O2 and organic hyperoxids, and ribonucleotide reduction	Trypanosoma brucei	?	-	?	89	
6.3.1.8	additional information	the trypanothione synthase also converts glutathionylspermidine further to trypanothione catalyzing the reaction of EC 6.3.1.9	Crithidia fasciculata	?	-	?	89	
6.3.1.8	additional information	model of ter-reactant mechanism of GspS catalysis and postulated overview	Crithidia fasciculata	?	-	?	89	
6.3.1.8	additional information	Escherichia coli proteins YgiC and YjfC, encoded by genes ygiC and yjfC, cannot synthesize G-Sp, GSH, or GSH intermediates, they are no glutathionylspermidine synthetase/amidases, but show ATP-hydrolysis activity	Escherichia coli	?	-	?	89