Pluralibacter now joins the (very) selected group of genera from which obligate nutritional symbionts of leeches have evolved from. As the previously known Providencia, this novel symbiont displays strong genome reduction w/convergent retention of B vitamin biosynthetic pathways. This discovery was surprising, as no change in bacteriome structure is observed (in leeches new symbiont=new bacteriome). Genomic features from the novel symbiont suggest it likely represents a symbiont replacement event, but future work should help clarify symbiont turnover in this leech genus.
This was a great collaboration with friends and work colleagues Alejandro Oceguera Figueroa (IB UNAM, Mexico) and Sebastian Kvist (Naturhistoriska riksmuseet, Sweden).
Reference: 10.1101/2023.12.21.572949
*Version of record: 10.1128/spectrum.04286-23