N(6)-L-threonylcarbamoyladenosine(37) in tRNA + (sulfur carrier)-SH + AH2 + S-adenosyl-L-methionine = 2-sulfanyl-N(6)-L-threonylcarbamoyladenosine(37) in tRNA + (sulfur carrier)-H + 5'-deoxyadenosine + L-methionine + A + H(+)
n(6)-l-threonylcarbamoyladenosine(37) in trna + (sulfur carrier)-sh + ah2 + s-adenosyl-l-methionine = 2-sulfanyl-n(6)-l-threonylcarbamoyladenosine(37) in trna + (sulfur carrier)-h + 5'-deoxyadenosine + l-methionine + a + h(+)