Premium
Stall no more at polyproline stretches with the translation elongation factors EF‐P and IF‐5A
Author(s) -
Lassak Jürgen,
Wilson Daniel N.,
Jung Kirsten
Publication year - 2016
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/mmi.13233
Subject(s) - biology , elongation factor , ribosome , polyproline helix , eukaryotic translation , translation (biology) , escherichia coli , biochemistry , transfer rna , microbiology and biotechnology , protein biosynthesis , rna , messenger rna , gene , peptide
Summary Synthesis of polyproline proteins leads to translation arrest. To overcome this ribosome stalling effect, bacteria depend on a specialized translation elongation factor P ( EF‐P ), being orthologous and functionally identical to eukaryotic/archaeal elongation factor e/a IF ‐5 A (recently renamed ‘ EF 5’). EF ‐ P binds to the stalled ribosome between the peptidyl‐t RNA binding and t RNA ‐exiting sites, and stimulates peptidyl‐transferase activity, thus allowing translation to resume. In their active form, both EF ‐ P and e/a IF ‐5 A are post‐translationally modified at a positively charged residue, which protrudes toward the peptidyl‐transferase center when bound to the ribosome. While archaeal and eukaryotic IF ‐5 A strictly depend on (deoxy‐) hypusination (hypusinylation) of a conserved lysine, bacteria have evolved diverse analogous modification strategies to activate EF ‐ P . In E scherichia coli and S almonella enterica a lysine is extended by β‐lysinylation and subsequently hydroxylated, whereas in P seudomonas aeruginosa and S hewanella oneidensis an arginine in the equivalent position is rhamnosylated. Inactivation of EF ‐ P , or the corresponding modification systems, reduces not only bacterial fitness, but also impairs virulence. Here, we review the function of EF ‐ P and IF ‐5 A and their unusual posttranslational protein modifications.