HMM Summary Page: TIGR00432

FunctiontRNA-guanine(15) transglycosylase
Gene SymboltgtA
Trusted Cutoff350.00
Domain Trusted Cutoff350.00
Noise Cutoff200.00
Domain Noise Cutoff200.00
Isology Typeequivalog
EC Number2.4.2.48
HMM Length637
Mainrole CategoryProtein synthesis
Subrole CategorytRNA and rRNA base modification
Gene Ontology TermGO:0006400: tRNA modification biological_process
GO:0016763: transferase activity, transferring pentosyl groups molecular_function
AuthorHaft DH
Entry DateApr 20 1999 2:06PM
Last ModifiedDec 21 2011 12:30PM
CommentThis tRNA-guanine transglycosylase (tgt) differs from the tgt of E. coli and other Bacteria in the site of action and the modification that results. It exchanges 7-cyano-7-deazaguanine (preQ0) with guanine at position 15 of archaeal tRNA; this nucleotide is subsequently converted to archaeosine, found exclusively in the Archaea. This enzyme from Haloferax volcanii has been purified, characterized, and partially sequenced and is the basis for identifying this family. In contrast, bacterial tgt (TIGR00430) catalyzes the exchange of preQ0 or preQ1 for the guanine base at position 34; this nucleotide is subsequently modified to queuosine. Archeoglobus fulgidus has both enzymes, while some other Archaea have just this one.
ReferencesRM Medline; 97390456 SE TIGR GA hmmls AL clustalw DR HAMAP; MF_01634; 19 of 32