Table S1.

General genome characteristics of N. moscoviensis and N. defluvii

Genome feature	N. moscoviensis	N. defluvii
Genome size, bp	4,589,485	4,317,083
Average G+C content, %	62	59
No. of CDS	4,863	4,274
Coding density, %	90.6	89.4
CDS with predicted function	2,391 (56%)	2,154 (50%)
rRNA operon	1	1
tRNA genes	47	46
Species-specific CDS*	2,161 (44%)	1,695 (40%)
Species-specific CDS with unknown function	1,547	1,216

CDS, coding sequences.

^*CDS with no homolog in the respective other Nitrospira genome were considered to be species-specific. Homologous proteins were defined as ≥30% identical over ≥80% of the amino acid sequence length.