Ornithine capture by a translating ribosome controls bacterial polyamine synthesis

Autor: Alba Herrero del Valle, C. Axel Innis, Britta Seip, Guénaël Sacheau, Iñaki Cervera-Marzal, A. Carolin Seefeldt
Rok vydání: 2020
Předmět:
Microbiology (medical)
Models
Molecular

Ornithine
Salmonella typhimurium
Immunology
Ornithine Decarboxylase
Applied Microbiology and Biotechnology
Microbiology
Ribosome
Article
Ornithine decarboxylase
03 medical and health sciences
chemistry.chemical_compound
Bacterial Proteins
RNA
Transfer

Genetics
Protein biosynthesis
Enterococcus faecalis
Escherichia coli
Polyamines
Protein Interaction Domains and Motifs
Amino Acid Sequence
Phylogeny
030304 developmental biology
0303 health sciences
Binding Sites
Base Sequence
Sequence Homology
Amino Acid

Virulence
030306 microbiology
Chemistry
Effector
Thermus thermophilus
Translation (biology)
Cell Biology
Cell biology
Transcription antitermination
Protein Biosynthesis
Release factor
Polyamine
Ribosomes
Sequence Alignment
Peptide Termination Factors
Protein Binding
Zdroj: Nature Microbiology
Nature microbiology
ISSN: 2058-5276
DOI: 10.1038/s41564-020-0669-1
Popis: Polyamines are essential metabolites that play an important role in cell growth, stress adaptation, and microbial virulence1–3. In order to survive and multiply within a human host, pathogenic bacteria adjust the expression and activity of polyamine biosynthetic enzymes in response to different environmental stresses and metabolic cues2. Here, we show that ornithine capture by the ribosome and the nascent peptide SpeFL controls polyamine synthesis in γ-proteobacteria by inducing the expression of the ornithine decarboxylase SpeF4, via a mechanism involving ribosome stalling and transcription antitermination. In addition, we present the cryo-EM structure of an Escherichia coli (E. coli) ribosome stalled during translation of speFL in the presence of ornithine. The structure shows how the ribosome and the SpeFL sensor domain form a highly selective binding pocket that accommodates a single ornithine molecule but excludes near-cognate ligands. Ornithine pre-associates with the ribosome and is then held in place by the sensor domain, leading to the compaction of the SpeFL effector domain and blocking the action of release factor RF1. Thus, our study not only reveals basic strategies by which nascent peptides assist the ribosome in detecting a specific metabolite, but also provides a framework for assessing how ornithine promotes virulence in several human pathogens.
Databáze: OpenAIRE