Table 1. Number of transposases per genome in, based on the taxonomic annotation of the metagenomic reads, strains most closely related to the Baltic Sea and Skagerrak Synechococcus populations.

Strain	Transposase count	Genome size (Mbp)	Transposases/Mbp	Strain origin
Coastal (Baltic Sea)
Synechococcus sp. CB0101	15	2,7	5,6	Chesapeake Bay
Synechococcus sp. CB0205	9	2,4	3,7	Chesapeake Bay
Synechococcus sp. RS9917	22	2,6	8,5	Red Sea
Synechococcus sp. WH5701	50	3,0	16,4	Long Island Sound
Marine (Skagerrak)
Synechococcus sp. BL107	0	2,3	0	Blanes Bay, Mediterranean Sea
Synechococcus sp. CC9311	0	2,6	0	California Current
Synechococcus sp. CC9902	0	2,2	0	California Current