Sequence Cluster id id2 desc organism isHeteromeric 1 Cluster1 TCDB::A2RKA7 3.A.1.2.17 Purine/cytidine ABC transporter ATP-binding protein, component of General nucleoside uptake porter, NupABC/BmpA (transports all common nucleosides as well as 5-fluorocytidine, inosine, deoxyuridine and xanthosine) (Martinussen et al., 2010) (Most similar to 3.A.1.2.12). NupA is 506aas with two ABC (C) domains. NupB has 8 predicted TMSs, NupC has 9 or 10 predicted TMSs in a 4 + 1 (or 2) + 4 arrangement Lactococcus lactis subsp. cremoris (strain MG1363) heteromer 2 Cluster1 TCDB::Q8DU37 3.A.1.2.12 RnsB, component of The (deoxy)ribonucleoside permease; probably takes up all deoxy- and ribonucleosides (cytidine, uridine, adenosine and toxic analogues, fluorocytidine and fluorouridine tested), but not ribose or nucleobases Streptococcus mutans heteromer