A Microscale Platform for the Comprehensive Analysis of Bacterial Translation Initiation

Area of Science:

• Molecular Biology
• Biochemistry
• Microbiology

Background:

• Prokaryotic translation initiation involves complex interactions between ribosomes, mRNA, initiator tRNA, and initiation factors.
• Traditional methods for studying these interactions face safety and methodological limitations.

Purpose of the Study:

• To present a novel fluorescence-based analytical platform integrating microscale thermophoresis (MST) for comprehensive analysis of bacterial translation initiation.
• To quantify assembly pathways and equilibria of translation initiation complexes.
• To provide a versatile framework for discovering novel protein synthesis inhibitors.

Main Methods:

• Development of a fluorescence-based platform using microscale thermophoresis (MST).
• Labeling of key components including initiator tRNA, mRNAs, initiation factors, and 70S ribosomes with fluorescent dyes (e.g., BODIPY).
• Validation of ribosome integrity and function using nano differential scanning fluorimetry, stopped-flow kinetics, and peptide synthesis assays.

Main Results:

• Quantification of assembly pathways and equilibria in multi-component translation initiation complexes.
• Demonstration of the platform's ability to probe initiation steps, including the role of magnesium ions and initiation factors.
• Characterization of the effects of antibiotics (e.g., streptomycin dissociation constant) and antimicrobial peptides (e.g., rumicidin-1) on translation initiation.
• Successful labeling of 70S ribosomes with BODIPY while preserving structural integrity and function.

Conclusions:

• The developed fluorescence-based MST platform offers a cost-effective, high-sensitivity alternative for studying bacterial translation initiation.
• This approach enhances mechanistic understanding of prokaryotic protein synthesis.
• The platform provides a versatile framework for the discovery and characterization of novel protein synthesis inhibitors.