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bioRxiv · 10.1101/2024.06.12.598653

Spaceflight Shifts in Community rRNA Copy Number in the Salivary Microbiome of Astronauts

Williamson, M. R.
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Abstract

The oral microbiome is stable, easily sampled, and can indicate disease. Using metagenomic data from GeneLab, I examined the effects of spaceflight on the human salivary microbiome using a composite community measure, average rRNA copy number. A higher copy number is associated with a faster growth rate and primary microbial succession. I found a significant increase in community weighted mean copy number between pre-spaceflight and during-spaceflight samples (p=0.0082). Furthermore, changes in abundance suggest a greater impact on individual species rather than phyla-level changes. Finally, a robustness analysis highlighted the importance of accurate copy number estimates and species-level identification. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=93 SRC="FIGDIR/small/598653v1_ufig1.gif" ALT="Figure 1"> View larger version (20K): org.highwire.dtl.DTLVardef@f079d9org.highwire.dtl.DTLVardef@1cfc53aorg.highwire.dtl.DTLVardef@19d7b5borg.highwire.dtl.DTLVardef@dcda3_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Williamson, M. R.. 2024-06-12. Spaceflight Shifts in Community rRNA Copy Number in the Salivary Microbiome of Astronauts. https://doi.org/10.1101/2024.06.12.598653

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