Post-translational modification by β-lysylation is required for activity of Escherichia coli elongation factor P (EF-P).

Bacterial elongation factor P (EF-P) is the ortholog of archaeal and eukaryotic initiation factor 5A (eIF5A). EF-P shares sequence homology and crystal structure with eIF5A, but unlike eIF5A, EF-P does not undergo hypusine modification. Recently, two bacterial genes, yjeA and yjeK, encoding truncated homologs of class II lysyl-tRNA synthetase and of lysine-2,3-aminomutase, respectively, have been implicated in the modification of EF-P to convert a specific lysine to a hypothetical β-lysyl-lysine.

Ribosome-dependent ATPase interacts with conserved membrane protein in Escherichia coli to modulate protein synthesis and oxidative phosphorylation.

Elongation factor RbbA is required for ATP-dependent deacyl-tRNA release presumably after each peptide bond formation; however, there is no information about the cellular role. Proteomic analysis in Escherichia coli revealed that RbbA reciprocally co-purified with a conserved inner membrane protein of unknown function, YhjD. Both proteins are also physically associated with the 30S ribosome and with members of the lipopolysaccharide transport machinery.

In vivo investigation of protein-protein interactions for helicases using tandem affinity purification.

A key component in determining the functional role of any protein is the elucidation of its binding partners using protein-protein interaction (PPI) data. Here we examine the use of tandem affinity purification (TAP) tagging to study RNA/DNA helicase PPIs in Escherichia coli. The tag, which consists of a calmodulin-binding region, a TEV protease recognition sequence, and an IgG-binding domain, is introduced into E.

Interactions of elongation factor EF-P with the Escherichia coli ribosome.

EF-P (eubacterial elongation factor P) is a highly conserved protein essential for protein synthesis. We report that EF-P protects 16S rRNA near the G526 streptomycin and the S12 and mRNA binding sites (30S T-site). EF-P also protects domain V of the 23S rRNA proximal to the A-site (50S T-site) and more strongly the A-site of 70S ribosomes.

Investigating the in vivo activity of the DeaD protein using protein-protein interactions and the translational activity of structured chloramphenicol acetyltransferase mRNAs.

Here, we report the use of an in vivo protein-protein interaction detection approach together with focused follow-up experiments to study the function of the DeaD protein in Escherichia coli. In this method, functions are assigned to proteins based on the interactions they make with others in the living cell. The assigned functions are further confirmed using follow-up experiments.