title: Evolution of tRNAPhe:imG2 methyltransferases involved in the biosynthesis of wyosine derivatives in Archaea.
abstract: Tricyclic wyosine derivatives are found at position 37 of eukaryotic and archaeal tRNAPheIn Archaea, the intermediate imG-14 is targeted by three different enzymes that catalyze the formation of yW-86, imG, and imG2. We have suggested previously that a peculiar methyltransferase (aTrm5a/Taw22) likely catalyzes two distinct reactions: N1-methylation of guanosine to yield m1G; and C7-methylation of imG-14 to yield imG2. Here we show that the recombinant aTrm5a/Taw22-like enzymes from both Pyrococcus abyssi and Nanoarchaeum equitans indeed possess such dual specificity. We also show that substitutions of individual conservative amino acids of P. abyssi Taw22 (P260N, E173A, and R174A) have a differential effect on the formation of m1G/imG2, while replacement of R134, F165, E213, and P262 with alanine abolishes the formation of both derivatives of G37. We further demonstrate that aTrm5a-type enzyme SSO2439 from Sulfolobus solfataricus, which has no N1-methyltransferase activity, exhibits C7-methyltransferase activity, thereby producing imG2 from imG-14. We thus suggest renaming such aTrm5a methyltransferases as Taw21 to distinguish between monofunctional and bifunctional aTrm5a enzymes.
authors.affiliation: Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Vilnius University, Vilnius 10222, Lithuania.|Department of Chemistry and Bioengineering, Vilnius Gediminas Technical University, Vilnius 10223, Lithuania.
authors.forename: Jaunius
authors.initials: J
authors.lastname: Urbonavičius
authors.affiliation: Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Vilnius University, Vilnius 10222, Lithuania.
authors.forename: Rasa
authors.initials: R
authors.lastname: Rutkienė
authors.affiliation: Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Vilnius University, Vilnius 10222, Lithuania.|Department of Chemistry and Bioengineering, Vilnius Gediminas Technical University, Vilnius 10223, Lithuania.
authors.forename: Anželika
authors.initials: A
authors.lastname: Lopato
authors.affiliation: Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Vilnius University, Vilnius 10222, Lithuania.
authors.forename: Daiva
authors.initials: D
authors.lastname: Tauraitė
authors.affiliation: Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Vilnius University, Vilnius 10222, Lithuania.
authors.forename: Jonita
authors.initials: J
authors.lastname: Stankevičiūtė
authors.affiliation: Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Vilnius University, Vilnius 10222, Lithuania.
authors.forename: Agota
authors.initials: A
authors.lastname: Aučynaitė
authors.affiliation: Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Vilnius University, Vilnius 10222, Lithuania.
authors.forename: Laura
authors.initials: L
authors.lastname: Kaliniene
authors.affiliation: Institut de Biologie Intégrative de la Cellule, I2BC, CNRS Université Paris-Sud UMR9198, Orsay, France.
authors.forename: Herman
authors.initials: H
authors.lastname: van Tilbeurgh
authors.affiliation: Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Vilnius University, Vilnius 10222, Lithuania.
authors.forename: Rolandas
authors.initials: R
authors.lastname: Meškys
mesh_terms: D000595:Amino Acid Sequence; D001105:Archaea / Q000378:metabolism*; D006151:Guanosine / Q000031:analogs & derivatives* / Q000096:biosynthesis; D008780:Methyltransferases / Q000737:chemistry / Q000378:metabolism*; D012360:RNA, Transfer, Phe / Q000737:chemistry / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid
chemical_list: D012360:RNA, Transfer, Phe; D006151:Guanosine; C012100:wyosine; D008780:Methyltransferases
keywords: Archaea; bifunctional enzyme; evolution; tRNA modification; wyosine