We downloaded ABC protein-related sequences from the Uniprot database with the keyword "Bacterial+ABC+transporter". Then used the local MEME tool to search for the conserved domains of these proteins and ORF7a protein. In the initial search results, there were too many motif fragments for one domain. For the convenience of analysis, we had merged the motif sequences by domain. The search results of domains and motifs related to the ABC transport system are shown in Table . ORF7a has ATP binding domains (AAA, AAA_15, CBIO, CBS, OppC_N, STAS, TOBE_2) and transmembrane domains (ABC transmembrane type-1, ABC transporter, ABC_tran_Xtn, ABC_transp_aux, ABC2_membrane). AMP-binding (Interpro entry: IPR000873) is the AMP binding region . The ATP binding domain overlaps the transmembrane domain."MKIILFLALITLATCELYHYQECVRGTTVLLKEPCSSGTYEGNSPFHPLADNKFAL TCFSTQFAFACPDGVKHVYQLRARSVSPKLFIRQEEVQELYSPIFLIVAAIVFI" (residues 1 -110) motif has the function of ATP binding and ABC transmembrane transport.