Table 1. Major genome characteristics of the six taxa of the genus Polynucleobacter compared in this study .
The upper four strains are currently classified as P. necessarius subsp. asymbioticus strains (Hahn et al., 2009), the obligate endosymbiont STIR1 is classified as P. necessarius subsp. necessarius (Boscaro et al., 2013), and strain ‘beta proteobacterium’ CB is lacking a sound classification (Hao et al., 2013) but clusters in 16S rRNA gene (Wang et al., 2009) and other phylogenetic trees (Figs 1 and 2) with P. necessarius strains.
| Strain | Lifestyle | Genome size (Mbp) | DNA G+C content (mol%) | DDBJ/EMBL/GenBank accession number | IMG Genome ID | Reference |
|---|---|---|---|---|---|---|
| MWH-HuW1T (=DSM 21492T) | Free-living | 2.32 | 45.5 | LOJJ00000000 | 2630969031 | This study |
| MWH-JaK3T (=DSM 21493T) | Free-living | 2.05 | 45.4 | LOJI00000000 | 2608642177 | This study |
| QLW-P1DMWA-1T (=DSM 18221T) | Free-living | 2.16 | 44.8 | CP000655 | 640427129 | Meincke et al. (2012) |
| MWH-MoK4T (=DSM 21495T) | Free-living | 2.03 | 45.2 | CP007501 | 2505313000 | Hahn et al. (2016) |
| 'beta proteobacterium' CB | Free-living | 2.05 | 46.1 | CP004348 | 2565956558 | Hao et al. (2013) |
| STIR1 (Euplotes aediculatus) | Endosymbiont | 1.56 | 45.6 | CP001010 | 2503982034 | Boscaro et al. (2013) |