Premium
Acquisition of a bacterial RumA‐type tRNA(uracil‐54, C5)‐methyltransferase by Archaea through an ancient horizontal gene transfer
Author(s) -
Urbonavičius Jaunius,
Auxilien Sylvie,
Walbott Hélène,
Trachana Kalliopi,
GolinelliPimpaneau Béatrice,
BrochierArmanet Céline,
Grosjean Henri
Publication year - 2008
Publication title -
molecular microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.857
H-Index - 247
eISSN - 1365-2958
pISSN - 0950-382X
DOI - 10.1111/j.1365-2958.2007.06047.x
Subject(s) - biology , transfer rna , gene , genetics , 23s ribosomal rna , methyltransferase , escherichia coli , horizontal gene transfer , ribosomal rna , microbiology and biotechnology , rna , genome , ribosome , methylation
Summary The Pyrococcus abyssi genome displays two genes possibly coding for S‐adenosyl‐ l ‐methionine‐dependent RNA(uracil, C5)‐methyltransferases (PAB0719 and PAB0760). Their amino acid sequences are more closely related to Escherichia coli RumA catalysing the formation of 5‐methyluridine (m 5 U)‐1939 in 23S rRNA than to E. coli TrmA ( tR NA m ethyltransferase A ) methylating uridine‐54 in tRNA. Comparative genomic and phylogenetic analyses show that homologues of PAB0719 and PAB0760 occur only in a few Archaea, these genes having been acquired via a single horizontal gene transfer from a bacterial donor to the common ancestor of Thermococcales and Nanoarchaea. This transfer event was followed by a duplication event in Thermococcales leading to two closely related genes. None of the gene products of the two P. abyssi paralogues catalyses in vitro the formation of m 5 U in a P. abyssi rRNA fragment homologous to the bacterial RumA substrate. Instead, PAB0719 enzyme (renamed Pab TrmU54) displays an identical specificity to TrmA, as it catalyses the in vitro formation of m 5 U‐54 in tRNA. Thus, during evolution, at least one of the two P. abyssi RumA‐type enzymes has changed of target specificity. This functional shift probably occurred in an ancestor of all Thermococcales. This study also provides new evidence in favour of a close relationship between Thermococcales and Nanoarchaea.