Transferases;
Transferring sulfur-containing groups;
Transferring alkylthio groups
BRITE hierarchy

tRNA (N6-L-threonylcarbamoyladenosine37):sulfur-(sulfur carrier),S-adenosyl-L-methionine C2-(methylsulfanyl)transferase

N6-L-threonylcarbamoyladenine37 in tRNA + sulfur-(sulfur carrier) + 2 S-adenosyl-L-methionine + reduced electron acceptor = 2-(methylsulfanyl)-N6-L-threonylcarbamoyladenine37 in tRNA + S-adenosyl-L-homocysteine + (sulfur carrier) + L-methionine + 5'-deoxyadenosine + electron acceptor (overall reaction) [RN:R10649];
(1a) N6-L-threonylcarbamoyladenine37 in tRNA + sulfur-(sulfur carrier) + S-adenosyl-L-methionine + reduced electron acceptor = 2-sulfanyl-N6-L-threonylcarbamoyladenine37 in tRNA + (sulfur carrier) + L-methionine + 5'-deoxyadenosine + electron acceptor [RN:R10650];
(1b) S-adenosyl-L-methionine + 2-sulfanyl-N6-L-threonylcarbamoyladenine37 in tRNA = S-adenosyl-L-homocysteine + 2-(methylsulfanyl)-N6-L-threonylcarbamoyladenine37 in tRNA [RN:R10651]

R10649 R10650 R10651
Reaction

N6-L-threonylcarbamoyladenine37 in tRNA;
sulfur-(sulfur carrier);
S-adenosyl-L-methionine [CPD:C00019];
reduced electron acceptor;
2-sulfanyl-N6-L-threonylcarbamoyladenine37 in tRNA

The enzyme, which is a member of the S-adenosyl-L-methionine-dependent radical (radical AdoMet) enzymes superfamily, binds two [4Fe-4S] clusters as well as the transferred sulfur. The sulfur donor is believed to be one of the [4Fe-4S] clusters, which is sacrificed in the process, so that in vitro the reaction is a single turnover. The identity of the electron donor is not known.

EC 2.8.4.5 created 2014, modified 2015