title: The flavoprotein Mcap0476 (RlmFO) catalyzes m5U1939 modification in Mycoplasma capricolum 23S rRNA.
abstract: Efficient protein synthesis in all organisms requires the post-transcriptional methylation of specific ribosomal ribonucleic acid (rRNA) and transfer RNA (tRNA) nucleotides. The methylation reactions are almost invariably catalyzed by enzymes that use S-adenosylmethionine (AdoMet) as the methyl group donor. One noteworthy exception is seen in some bacteria, where the conserved tRNA methylation at m5U54 is added by the enzyme TrmFO using flavin adenine dinucleotide together with N5,N10-methylenetetrahydrofolate as the one-carbon donor. The minimalist bacterium Mycoplasma capricolum possesses two homologs of trmFO, but surprisingly lacks the m5U54 tRNA modification. We created single and dual deletions of the trmFO homologs using a novel synthetic biology approach. Subsequent analysis of the M. capricolum RNAs by mass spectrometry shows that the TrmFO homolog encoded by Mcap0476 specifically modifies m5U1939 in 23S rRNA, a conserved methylation catalyzed by AdoMet-dependent enzymes in all other characterized bacteria. The Mcap0476 methyltransferase (renamed RlmFO) represents the first folate-dependent flavoprotein seen to modify ribosomal RNA.
authors.affiliation: INRA, UMR 1332 de Biologie du Fruit et Pathologie, F-33140 Villenave d'Ornon, France Université de Bordeaux, UMR 1332 de Biologie du Fruit et Pathologie, F-33140 Villenave d'Ornon, France.
authors.forename: Carole
authors.initials: C
authors.lastname: Lartigue
authors.affiliation: INRA, UMR 1332 de Biologie du Fruit et Pathologie, F-33140 Villenave d'Ornon, France Université de Bordeaux, UMR 1332 de Biologie du Fruit et Pathologie, F-33140 Villenave d'Ornon, France.
authors.forename: Anne
authors.initials: A
authors.lastname: Lebaudy
authors.affiliation: INRA, UMR 1332 de Biologie du Fruit et Pathologie, F-33140 Villenave d'Ornon, France Université de Bordeaux, UMR 1332 de Biologie du Fruit et Pathologie, F-33140 Villenave d'Ornon, France.
authors.forename: Alain
authors.initials: A
authors.lastname: Blanchard
authors.affiliation: Department of Microbiology and Cell Science, University of Florida, FL 32611, USA.
authors.forename: Basma
authors.initials: B
authors.lastname: El Yacoubi
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Southern Denmark, DK-5230 Odense M, Denmark.
authors.forename: Simon
authors.initials: S
authors.lastname: Rose
authors.affiliation: Centre de Génétique Moléculaire, UPR3404, CNRS, Associée à l'Université Paris Sud 11, FRC 3115, F-91190 Gif-sur-Yvette, France henri.grosjean@cgm.cnrs-gif.fr.
authors.forename: Henri
authors.initials: H
authors.lastname: Grosjean
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Southern Denmark, DK-5230 Odense M, Denmark srd@bmb.sdu.dk.
authors.forename: Stephen
authors.initials: S
authors.lastname: Douthwaite
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D055162:Biocatalysis; D005420:Flavoproteins / Q000235:genetics / Q000378:metabolism*; D008745:Methylation; D008780:Methyltransferases / Q000235:genetics / Q000378:metabolism*; D045623:Mycoplasma capricolum / Q000201:enzymology* / Q000235:genetics; D012338:RNA, Ribosomal, 23S / Q000737:chemistry / Q000378:metabolism*; D012343:RNA, Transfer / Q000378:metabolism; D014529:Uridine / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D005420:Flavoproteins; D012338:RNA, Ribosomal, 23S; D012343:RNA, Transfer; D008780:Methyltransferases; D014529:Uridine