Identification of a bifunctional enzyme MnmC involved in the biosynthesis of a hypermodified uridine in the wobble position of tRNA.
The gene encoding the bifunctional enzyme MnmC that catalyzes the two last steps in the biosynthesis of 5-methylaminomethyl-2-thiouridine (mnm5s2U) in tRNA has been previously mapped at about 50 min on the Escherichia coli K12 chromosome, but to date the identity of the corresponding enzyme has not been correlated with any of the known open reading frames (ORFs). Using the protein fold-recognition approach, we predicted that the 74-kDa product of the yfcK ORF located at 52.6 min and annotated as "putative peptidase" comprises a methyltransferase domain and a FAD-dependent oxidoreductase domain. We have cloned, expressed, and purified the YfcK protein and demonstrated that it catalyzes the formation of mnm5s2U in tRNA. Thus, we suggest to rename YfcK as MnmC.
Bujnicki
Janusz M
JM
Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology, Warsaw, Poland.
Oudjama
Yamina
Y
Roovers
Martine
M
Owczarek
Sylwia
S
Caillet
Joël
J
Droogmans
Louis
L
D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D019295:Computational Biology; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D029968:Escherichia coli Proteins / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D009097:Multienzyme Complexes / Q000235:genetics* / Q000378:metabolism; D012343:RNA, Transfer / Q000096:biosynthesis*; D016415:Sequence Alignment; D013891:Thiouridine / Q000031:analogs & derivatives* / Q000378:metabolism*
D029968:Escherichia coli Proteins; C488767:MnmC protein, E coli; D009097:Multienzyme Complexes; D013891:Thiouridine; C011916:5-methylaminomethyl-2-thiouridine; D012343:RNA, Transfer