Transmembrane structure binding sites (TMD). The transmembrane structure binding sites include ABC transmembrane type-1, ABC transporter, ABC_tran_Xtn, ABC_transp_aux, ABC2_membrane domains. ABC transmembrane type-1 (Interpro entry: IPR011527) represents the transmembrane domain when the TMD and ABC regions are found in the same protein . ABC_transp_aux (Interpro entry: IPR019196, Pfam: PF09822) belongs to the ABC type non-characteristic transport system. This domain is found in various eukaryotic and prokaryotic intraflagellar transporters and several hypothetical proteins involved in a gliding motion. ABC2_membrane (Pfam: PF01061, Interpro entry: IPR013525) belongs to the transmembrane structure of the ABC-2 transporter . ABC transporter (Pfam: PF00005, Interpro entry: IPR003439) belongs to the ATP-binding cassette (ABC) superfamily, which uses the hydrolysis of ATP to provide energy for various biological systems . The ABC transporter comprises at least two conserved regions: the highly conserved ATP-binding cassette (ABC) and the less conserved transmembrane domain (TMD). ABC_tran_Xtn (Interpro entry: IPR032781) is the ABC-transporter extension domain bound to the ribosome to stabilize the interaction . In summary, the ABC transmembrane domain (TMD) of ORF7a in Table is at sites 1-110, and the first half of the sequence overlaps with the two ATP binding sites.