Bacteria's Secret Weapon: YebC!

The field of bacterial translation has long been a focal point for understanding fundamental biological processes and identifying potential targets for antimicrobial strategies. While the core machinery of protein synthesis, the ribosome, is well-understood, the nuanced roles of various accessory factors that fine-tune this process are continuously being uncovered. These factors include RNA-binding proteins (RBPs), a diverse group of molecules critical for regulating gene expression at the post-transcriptional level. However, it remains hard to fully understand many RBPs and their specific functions in bacterial physiology and pathogenesis are still being clarified. A paper of the Molecular Microbiology Group (Marc Erhardt) delves into this fascinating area by identifying novel RBPs in the human pathogen Streptococcus pyogenes and uncovers the role of the conserved protein YebC in optimizing the translation of challenging amino acid sequences. They also studied its effect on physiology and virulence of the bacteria. If you want to know everything about YebC in bacteria, read the Nature Communications Article.

Abstract

The ribosome employs a set of highly conserved translation factors to efficiently synthesise proteins. Some translation factors interact with the ribosome in a transient manner and are thus challenging to identify. However, proteins involved in translation can be specifically identified by their interaction with ribosomal RNAs. Using a combination of proteomics approaches, we identified 30 previously uncharacterized RNA-binding proteins in the pathogenic bacterium Streptococcus pyogenes. One of these, a widely conserved protein YebC, was shown to transiently interact with 23S rRNA near the peptidyl-transferase centre. Deletion of yebC moderately affected the physiology and virulence of S. pyogenes. We performed ribosome profiling and detected increased pausing at proline-rich amino acid motifs in the absence of functional YebC. Further experiments in S. pyogenes and Salmonella Typhimurium and using an in vitro translation system suggested that YebC is a translation factor required for efficient translation of proteins with proline-rich motifs.