Genome comparison
Genome synteny was analyzed using ProgressiveMauve (Darling, Mau, & Perna, 2010). The complete closed genome of the Neisseria -related symbiont from H. acanthopus was aligned to the 39 contigs of theNeisseria -related symbiont from P. serrata , yielding 27 Locally Collinear Blocks (Figure 1). The resulting synteny regions are explored in more detail in SupplementaryData1. To provide a comparison of selected metabolic pathways, we extended the analysis from our previous work on Legionella polyplacis (Rihova, Novakova, Husnik, & Hypsa, 2017) which followed the selection of genes published by Moran, McCutcheon and Nakabachi (2008). The comparison was based on the RAST annotation for the two Neisseria -related symbionts, and the KEGG database (Kanehisa, Sato, Kawashima, Furumichi, & Tanabe, 2016) for our other bacteria.