{PDOC00871} {PS01131; RRNA_A_DIMETH} {BEGIN} ************************************************ * Ribosomal RNA adenine dimethylases signature * ************************************************ A number of enzymes responsible for the dimethylation of adenosines in ribosomal RNAs (EC 2.1.1.48) have been found [1,2] to be evolutionary related. These enzymes are: - Bacterial 16S rRNA dimethylase (gene ksgA), which acts in the biogenesis of ribosomes by catalyzing the dimethylation of two adjacent adenosines in the loop of a conserved hairpin near the 3'-end of 16S rRNA. Inactivation of ksgA leads to resistance to the aminoglycoside antibiotic kasugamycin. - Yeast 18S rRNA dimethylase (gene DIM1), which is functionally similar to ksgA and that dimethylates twin adenosines in the 3'-end of 18S rRNA. - Bacterial 'erm' methylases. These enzymes confer resistance to macrolide- lincosamide-streptogramin B (MLS) antibiotics - such as erythromycin - by dimethylating the adenine residue at position 2058 of 23S rRNA thus resulting in a reduced affinity between ribosomes and the MLS antibiotics. - Caenorhabditis elegans hypothetical protein EO2H1.1. The best conserved region in these enzymes is located in the N-terminal section and corresponds to a region that is probably involved in S-adenosyl methionine (SAM) binding. -Consensus pattern: [LIVMAC]-[LIVMFYWT]-[DE]-x-G-[STAPVLCG]-G-x-[GAS]-x- [LIVMF]-[ST]-x(2,3)-[LIVMA]-x(5,8)-[LIVMYF]-x-[STAGVLC]- [LIVMFYHCS]-E-x-D -Sequences known to belong to this class detected by the pattern: ALL. -Other sequence(s) detected in Swiss-Prot: NONE. -Last update: April 2006 / Pattern revised. [ 1] van Gemen B., van Knippenberg P.H. (In) Nucleic acid methylation, Clawson G.A., Willis D.B., Weissbach A., Jones P.A., Eds., pp.19-36, Alan R. Liss Inc, New-York, (1990). [ 2] Lafontaine D., Delcour J., Glasser A.L., Desgres J., Vandenhaute J. "The DIM1 gene responsible for the conserved m6(2)Am6(2)A dimethylation in the 3'-terminal loop of 18 S rRNA is essential in yeast." J. Mol. Biol. 241:492-497(1994). PubMed=8064863; -------------------------------------------------------------------------------- PROSITE is copyrighted by the SIB Swiss Institute of Bioinformatics and distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives (CC BY-NC-ND 4.0) License, see https://prosite.expasy.org/prosite_license.html -------------------------------------------------------------------------------- {END}