| 'DNA uptake and release' T4SSs |
| # | Name | Organism | Replicon | Location | Function |
| 1 | ComB  | Helicobacter pylori 26695 | chromosome [NC_000915] | 13702..16611; 36556..40581 | DNA uptake |
| 2 | ComB | Helicobacter pylori B38 | chromosome [NC_012973] | 13578..16487; 36264..40300 | DNA uptake |
| 3 | ComB | Helicobacter pylori B8 | chromosome [NC_014256] | 1551606..1555642; 1575414..1578323 | DNA uptake |
| 4 | ComB | Helicobacter pylori G27 | chromosome [NC_011333] | 13476..16385; 36329..40365 | DNA uptake |
| 5 | ComB | Helicobacter pylori J99 | chromosome [NC_000921] | 13859..16768; 36686..40719 | DNA uptake |
| 6 | ComB | Helicobacter pylori P12 | chromosome [NC_011498] | 13587..16496; 36339..40378 | DNA uptake |
| 7 | ComB | Helicobacter pylori Shi470 | chromosome [NC_010698] | 13456..16365; 34441..38459 | DNA uptake |
| 8 | Tra_F | Neisseria gonorrhoeae NCCP11945 | chromosome [NC_011035] | 866326..886920 | DNA release |
| T4SS derived from experimental literature | |||||