Mitochondrial methionyl-tRNA transformylase from bovine liver.
Substrate specificities of mammalian mitochondrial methionyl-tRNA transformylase (MTFmt) toward tRNA substrates were characterized in vitro. The MTFmt is able to formylate E. coli initiator methionyl-tRNA (Met-tRNA(fMet)) as efficiently as mammalian mitochondrial methionyl-tRNA. Furthermore, E. coli elongator methionyl-tRNA (Met-tRNA(mMet)) also serves as a substrate for mt MTF, whereas E. coli MTF rigorously excludes E. coli Met-tRNA(mMet) from formylation reaction. Thus, mammal mt MTF is suggested to have recognition mechanism different from E. coli MTF. To pursue the relationship between protein structure and unexpected substrate specificity of mammalian MTFmt, the nucleotide sequence of MTFmt gene was determined and its amino acids sequence was compared to other MTFs of prokaryotic origin.
Takeuchi
N
N
Department of Chemistry and Biotechnology, School of Engineering, University of Tokyo, Japan.
Kawakami
M
M
Ueda
T
T
Spremulli
L L
LL
Watanabe
K
K
D000818:Animals; D002417:Cattle; D004926:Escherichia coli; D019877:Hydroxymethyl and Formyl Transferases / Q000378:metabolism*; D007700:Kinetics; D008930:Mitochondria, Liver / Q000201:enzymology*; D012329:RNA, Bacterial / Q000378:metabolism; D012358:RNA, Transfer, Met / Q000378:metabolism; D013379:Substrate Specificity
D012329:RNA, Bacterial; D012358:RNA, Transfer, Met; D019877:Hydroxymethyl and Formyl Transferases; C021561:methionyl-tRNA formyltransferase