Substrate specificity of the pseudouridine synthase RluD in Escherichia coli

FEBS J. 2007 Nov;274(21):5759-66. doi: 10.1111/j.1742-4658.2007.06101.x. Epub 2007 Oct 12.


Pseudouridine synthase RluD converts uridines at positions 1911, 1915, and 1917 of 23S rRNA to pseudouridines. These nucleotides are located in the functionally important helix-loop 69 of 23S rRNA. RluD is the only pseudouridine synthase that is required for normal growth in Escherichia coli. We have analyzed substrate specificity of RluD in vivo. Mutational analyses have revealed: (a) RluD isomerizes uridine in vivo only at positions 1911, 1915, and 1917, regardless of the presence of uridine at other positions in the loop of helix 69 of 23S rRNA variants; (b) substitution of one U by C has no effect on the conversion of others (i.e. formation of pseudouridines at positions 1911, 1915, and 1917 are independent of each other); (c) A1916 is the only position in the loop of helix 69, where mutations affect the RluD specific pseudouridine formation. Pseudouridines were determined in the ribosomal particles from a ribosomal large subunit defective strain (RNA helicase DeaD(-)). An absence of pseudouridines in the assembly precursor particles suggests that RluD directed isomerization of uridines occurs as a late step during the assembly of the large ribosomal subunit.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Escherichia coli / enzymology*
  • Escherichia coli Proteins / chemistry*
  • Escherichia coli Proteins / metabolism*
  • Hydro-Lyases / chemistry*
  • Hydro-Lyases / metabolism*
  • Molecular Sequence Data
  • Nucleic Acid Conformation
  • Point Mutation
  • Pseudouridine / biosynthesis*
  • RNA, Ribosomal, 23S / genetics
  • RNA, Ribosomal, 23S / metabolism
  • Substrate Specificity


  • Escherichia coli Proteins
  • RNA, Ribosomal, 23S
  • Pseudouridine
  • Hydro-Lyases
  • RluD protein, E coli