Identification of a gene involved in the generation of 4-thiouridine in tRNA.
All organisms modify the bases of their RNA after transcription. Relatively little is known about the functions that these chemical alterations serve and, with very few exceptions, even less has been established regarding the enzymology involved. One modified base of known function is 4-thiouridine at position 8 of certain bacterial tRNAs, which serves as a photosensor for near-UV light. A gene involved in the conversion of uridine at position 8 into 4-thiouridine has been identified by genetic screening and its role in 4-thiouridine generation has been confirmed biochemically. This same gene, thiI , has recently been shown to play a role in thiamin biosynthesis. The purification and characteristics of the purified protein are also reported.
Mueller
E G
EG
Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA. emueller@udel.edu
Buck
C J
CJ
Palenchar
P M
PM
Barnhart
L E
LE
Paulson
J L
JL
D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics; D001483:Base Sequence; D002417:Cattle; D004926:Escherichia coli / Q000235:genetics* / Q000528:radiation effects; D029968:Escherichia coli Proteins; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D012343:RNA, Transfer; D013466:Sulfurtransferases; D013891:Thiouridine / Q000378:metabolism*; D014466:Ultraviolet Rays
D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D013891:Thiouridine; D012343:RNA, Transfer; D013466:Sulfurtransferases; C107110:ThiI protein, bacteria; C491479:thiI protein, E coli