|Title||The Fic protein Doc uses an inverted substrate to phosphorylate and inactivate EF-Tu.|
|Publication Type||Journal Article|
|Year of Publication||2013|
|Authors||Castro-Roa, D., Garcia-Pino A., De Gieter S., van Nuland N. A. J., Loris R., and Zenkin N.|
|Journal||Nat Chem Biol|
|Date Published||2013 Dec|
|Type of Article||ta|
|Keywords||Escherichia coli Proteins, Gene Expression Regulation, Bacterial, Guanosine Triphosphate, Models, Molecular, Mutation, Nucleotidyltransferases, Peptide Elongation Factor Tu, Phosphorylation, Protein Folding, RNA, Transfer|
Fic proteins are ubiquitous in all of the domains of life and have critical roles in multiple cellular processes through AMPylation of (transfer of AMP to) target proteins. Doc from the doc-phd toxin-antitoxin module is a member of the Fic family and inhibits bacterial translation by an unknown mechanism. Here we show that, in contrast to having AMPylating activity, Doc is a new type of kinase that inhibits bacterial translation by phosphorylating the conserved threonine (Thr382) of the translation elongation factor EF-Tu, rendering EF-Tu unable to bind aminoacylated tRNAs. We provide evidence that EF-Tu phosphorylation diverged from AMPylation by antiparallel binding of the NTP relative to the catalytic residues of the conserved Fic catalytic core of Doc. The results bring insights into the mechanism and role of phosphorylation of EF-Tu in bacterial physiology as well as represent an example of the catalytic plasticity of enzymes and a mechanism for the evolution of new enzymatic activities.
|Alternate Journal||Nat. Chem. Biol.|
|PubMed Central ID||PMC3836179|
|Grant List||202994 / / European Research Council / International |
BB/J006378/1 / / Biotechnology and Biological Sciences Research Council / United Kingdom
/ / Biotechnology and Biological Sciences Research Council / United Kingdom
The Fic protein Doc uses an inverted substrate to phosphorylate and inactivate EF-Tu.