Immunogen sequence: MREYKVVVLG SGGVGKSALT VQFVTGSFIE KYDPTIEDFY RKEIEVDSSP SVLEILDTAG TEQFASMRDL YIKNGQGFIL VYSLVNQQSF QDIKPMRDQI IRVKRYERVP MILVGNKVDL EGEREVSYGE GKALAEEWSC PFMETSAKNK ASVDELFAEI VRQMNYAAQP NGDEGCCSAC VIL. This intronless gene belongs to