Genomics, Proteomics, Bioinformatics

Evolutionary Flexibility of Ribosome Biogenesis in Bacteria

By Keith Cowing

Status Report

Molecular Biology and Evolution

December 11, 2025

Filed under evolution, genomics, Metabolism, Molecular Biology and Evolution, origin of life, Patescibacteria, protein synthesis, ribosome

Evolutionary Flexibility of Ribosome Biogenesis in Bacteria — Ribosome biogenesis processes and sets of RBFs in bacteria. a)Schematic view of multi-step ribosome biogenesis including the list of RBFs and tertiary structure of RPs, 70S, 50S and 30S subunits (PDB code: 4YBB, 5UYN, 6ENF, and 1RQU). The structure was visualized using CueMol. b) Boxplot representation of the number of BFs across different phyla in bacteria. Firmicutes are divided into seven groups in the AnnoTree database. * indicates fau-1, recently designated as a gene of RNase W (Vayssières et al. 2024). ** indicates a P-value of ≤ 0.01. — Molecular Biology and Evolution

Ribosomes are essential for protein synthesis and require ribosome biogenesis factors for assembly.

To uncover the evolutionary diversity of ribosome biogenesis, we analyzed over 30,000 bacterial genomes and revealed that Candidate Phyla Radiation, also known as the phylum Patescibacteria, characterized by reduced genomes and smaller ribosomes, has about half the average number of ribosome biogenesis factors compared with non-Candidate Phyla Radiation bacteria.

Notably, key ribosome biogenesis factors such as der, obgE, and rbfA, considered indispensable, are conserved in only around 20%-70% of Candidate Phyla Radiation genomes. Since such repertoires were not observed in reduced genomes of other phyla, Candidate Phyla Radiation presumably diverged early in bacterial evolution.

We further confirmed that ribosomal structural changes correlate with reduced ribosome biogenesis factor, evidencing co-evolution between ribosome biogenesis factor and the ribosome.

These findings suggest that ribosomal biogenesis is more flexible than recognized, and the small cell and genome sizes of Candidate Phyla Radiation bacteria and their early divergence may influence the unusual repertoires of ribosome biogenesis factors.

Evolutionary Flexibility of Ribosome Biogenesis in Bacteria, Molecular Biology and Evolution via PubMed (open access)
Evolutionary Flexibility of Ribosome Biogenesis in Bacteria, Molecular Biology and Evolution (open access)

Astrobiology,

Keith Cowing

Explorers Club Fellow, ex-NASA Space Station Payload manager/space biologist, Away Teams, Journalist, Lapsed climber, Synaesthete, Na’Vi-Jedi-Freman-Buddhist-mix, ASL, Devon Island and Everest Base Camp veteran, (he/him) 🖖🏻

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