The RNA cargo of Myxococcus outer membrane vesicles

Area of Science:

• Microbiology
• Bacterial genetics
• Molecular biology

Background:

• Gram-negative bacteria release outer membrane vesicles (OMVs) containing RNA that can influence target cells.
• Predatory myxobacteria utilize OMVs, but the role of their RNA cargo in prey killing is unknown.

Purpose of the Study:

• To investigate the RNA cargo of antimicrobial OMVs from predatory myxobacteria.
• To determine if specific RNA molecules are packaged into OMVs for potential delivery to prey cells.

Main Methods:

• Purification of OMVs and cells from four *Myxococcus* spp. strains.
• RNA-sequencing (RNA-seq) for transcriptome analysis of both cellular and OMV RNA.
• Comparative analysis of RNA abundance between cellular and OMV fractions.

Main Results:

• Myxobacterial OMVs contain distinct RNA profiles, with some transcripts showing non-specific packaging but others exclusively found in OMVs.
• A consistent set of 'core' OMV transcripts were identified across replicates and strains, sometimes enriched compared to cellular levels.
• Five specific core transcripts, including those for alkyl hydroperoxidases, ribosome-associated inhibitors, and a protease, were highlighted for further investigation.

Conclusions:

• Myxobacterial OMV RNA cargo is not solely a random sample of the cellular transcriptome, indicating selective packaging.
• The identified core OMV transcripts may play a functional role in inter-bacterial interactions, potentially contributing to prey cell killing.
• Further research is warranted to elucidate the biological function of these specific OMV-associated transcripts in prey cells.