Phyloproteomic and functional analyses do not support a split in the genus Borrelia (phylum Spirochaetes)

Area of Science:

• Microbiology
• Evolutionary Biology
• Bioinformatics

Background:

• Phylogenetic trees from molecular sequences lack functional information.
• Assessing functional relationships within Spirochaetes phylum using protein data.
• Hypothesis: Borrelia genus may require splitting into two distinct genera.

Purpose of the Study:

• To evaluate functional relationships among Spirochaetes bacteria.
• To test the hypothesis of splitting the Borrelia genus.
• To determine if functional data supports taxonomic reclassification.

Main Methods:

• Analyzed biological processes of 42,489 proteins from 34 Spirochaetes species reference proteomes.
• Utilized detrended canonical analysis and phyloproteomic networks.
• Constructed dendrograms based on protein presence/absence in reference proteomes.

Main Results:

• Borrelia species showed strong functional similarity, not separating them from other Spirochaetes.
• Borrelia were more similar to each other than to free-living or pathogenic non-vector Spirochaetes.
• Functional innovation in Borrelia was low compared to other Spirochaetes genera.

Conclusions:

• Marginal functional differences were observed among Borrelia species.
• Phyloproteomic networks proved effective for evaluating evolutionary relationships.
• Current data does not support splitting arthropod-transmitted spirochaetes into Borrelia and Borreliella genera.