2.8.1.B3	additional information	ThiI is responsible for the formation of the modified base 4-thiouridine found at position 8 in some prokaryotic tRNAs. This base acts as a sensitive trigger for the response mechanism to UV exposure, providing protection against its damaging effects	Bacillus anthracis	?	-	?	89	
2.8.1.B3	additional information	the enzyme also catalyzes the transfer of sulfur from thiosulfate to cyanide (EC 2.8.1.1)	Escherichia coli	?	-	?	89	
2.8.1.B3	additional information	the RLD-containing protein ThiI also acts as a sulfur carrier for generating ThiS-COSH. ThiI accepts a persulfide sulfur from IscS, then transfers the sulfur for thiocarboxylate formation to the C-terminus of ThiS which is catalyzed by ThiF	Escherichia coli	?	-	?	89	
2.8.1.B3	additional information	the enzyme is not able to enhance cysteine desulfurase NifZ activity of sulfide or alanine formation	Bacillus subtilis	?	-	?	89	
2.8.1.B3	additional information	three domains of ThiI are essential for the thiolation of tRNA: a THUMP domain that binds tRNA, an AANH domain that activates the uridine residue by adenylylation, and a rhodanese domain that transfers sulfur to the activated uridine residue. Only the rhodanese domain of the ThiI protein is required for a key thiolation reaction in the synthesis of thiamine, while the other two domains (THUMP and AANH) are dispensable	Escherichia coli	?	-	?	89	
2.8.1.B3	additional information	the enzyme also displays an ATP diphosphatase activity for the adenylation of uridine	Escherichia coli	?	-	?	89	
2.8.1.B3	additional information	the enzyme is not able to enhance cysteine desulfurase NifZ activity of sulfide or alanine formation	Bacillus subtilis PS832	?	-	?	89	
2.8.1.B3	sulfide + adenylated-tRNA-uridine(position8)	sulfide is able to replace IscS/cysteine as a substrate for 4-thiouridine synthesis	Escherichia coli	tRNA-4-thiouridine(position8) + ?	-	?	401982	
2.8.1.B3	sulfurtransferase IscS-SSH + adenylated-tRNA-uridine(position8)	-	Bacillus subtilis	sulfurtransferase IscS-SH + tRNA-4-thiouridine(position8) + AMP	-	?	399029	
2.8.1.B3	sulfurtransferase IscS-SSH + adenylated-tRNA-uridine(position8)	-	Escherichia coli	sulfurtransferase IscS-SH + tRNA-4-thiouridine(position8) + AMP	-	?	399029