Potassium-transporting ATPase subunit beta (Gastric H(+)/K(+) ATPase subunit beta) (Proton pump beta chain)
1_MAALQ 6_ EKKTC 11_ GQRME 16_ EFQRY 21_ CWNPD 26_ TGQML 31_ GRTLS 36_ RWVWI 41_ SLYYV 46_ AFYVV 51_ MTGLF 56_ ALCLY 61_ VLMQT 66_ VDPYT 71_ PDYQD 76_ QLRSP 81_ GVTLR 86_ PDVYG 91_ EKGLE 96_ IVYNV 101_ SDNRT 106_ WADLT 111_ QTLHA 116_ FLAGY 121_ SPAAQ 126_ EDSIN 131_ CTSEQ 136_ YFFQE 141_ SFRAP 146_ NHTKF 151_ SCKFT 156_ ADMLQ 161_ NCSGL 166_ ADPNF 171_ GFEEG 176_ KPCFI 181_ IKMNR 186_ IVKFL 191_ PSNGS 196_ APRVD 201_ CAFLD 206_ QPREL 211_ GQPLQ 216_ VKYYP 221_ PNGTF 226_ SLHYF 231_ PYYGK 236_ KAQPH 241_ YSNPL 246_ VAAKL 251_ LNIPR 256_ NAEVA 261_ IVCKV 266_ MAEHV 271_ TFNNP 276_ HDPYE 281_ GKVEF 286_KLKIE
1: The beta subunit of the gastric H(+)/K(+) ATPase pump which transports H(+) ions in exchange for K(+) ions across the apical membrane of parietal cells. Plays a structural and regulatory role in the assembly and membrane targeting of a functionally active pump (By similarity). Within a transport cycle, the transfer of a H(+) ion across the membrane is coupled to ATP hydrolysis and is associated with a transient phosphorylation of the alpha subunit that shifts the pump conformation from inward-facing (E1) to outward-facing state (E2). Interacts with the phosphorylation domain of the alpha subunit and functions as a ratchet, stabilizing the lumenal-open E2 conformation and preventing the reverse reaction of the transport cycle (By similarity)