ID   MJK1_METJA              Reviewed;         333 AA.
AC   Q57604;
DT   01-NOV-1997, integrated into UniProtKB/Swiss-Prot.
DT   01-NOV-1997, sequence version 1.
DT   25-MAY-2022, entry version 125.
DE   RecName: Full=Potassium channel protein 1;
DE   AltName: Full=MjK1;
GN   OrderedLocusNames=MJ0138.1;
OS   Methanocaldococcus jannaschii (strain ATCC 43067 / DSM 2661 / JAL-1 / JCM
OS   10045 / NBRC 100440) (Methanococcus jannaschii).
OC   Archaea; Euryarchaeota; Methanomada group; Methanococci; Methanococcales;
OC   Methanocaldococcaceae; Methanocaldococcus.
OX   NCBI_TaxID=243232;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=ATCC 43067 / DSM 2661 / JAL-1 / JCM 10045 / NBRC 100440;
RX   PubMed=8688087; DOI=10.1126/science.273.5278.1058;
RA   Bult C.J., White O., Olsen G.J., Zhou L., Fleischmann R.D., Sutton G.G.,
RA   Blake J.A., FitzGerald L.M., Clayton R.A., Gocayne J.D., Kerlavage A.R.,
RA   Dougherty B.A., Tomb J.-F., Adams M.D., Reich C.I., Overbeek R.,
RA   Kirkness E.F., Weinstock K.G., Merrick J.M., Glodek A., Scott J.L.,
RA   Geoghagen N.S.M., Weidman J.F., Fuhrmann J.L., Nguyen D., Utterback T.R.,
RA   Kelley J.M., Peterson J.D., Sadow P.W., Hanna M.C., Cotton M.D.,
RA   Roberts K.M., Hurst M.A., Kaine B.P., Borodovsky M., Klenk H.-P.,
RA   Fraser C.M., Smith H.O., Woese C.R., Venter J.C.;
RT   "Complete genome sequence of the methanogenic archaeon, Methanococcus
RT   jannaschii.";
RL   Science 273:1058-1073(1996).
RN   [2]
RP   FUNCTION.
RC   STRAIN=ATCC 43067 / DSM 2661 / JAL-1 / JCM 10045 / NBRC 100440;
RX   PubMed=12860407; DOI=10.1016/s0014-5793(03)00706-3;
RA   Hellmer J., Zeilinger C.;
RT   "MjK1, a K+ channel from M. jannaschii, mediates K+ uptake and K+
RT   sensitivity in E. coli.";
RL   FEBS Lett. 547:165-169(2003).
CC   -!- FUNCTION: Potassium channel protein. Seems to conduct potassium at low
CC       membrane potentials. {ECO:0000269|PubMed:12860407}.
CC   -!- SUBUNIT: Homotetramer. {ECO:0000305}.
CC   -!- SUBCELLULAR LOCATION: Cell membrane {ECO:0000305}; Multi-pass membrane
CC       protein {ECO:0000305}.
CC   -!- MISCELLANEOUS: Inhibited by barium and cesium.
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DR   EMBL; L77117; AAB98130.1; -; Genomic_DNA.
DR   PIR; D64317; D64317.
DR   RefSeq; WP_010869633.1; NC_000909.1.
DR   AlphaFoldDB; Q57604; -.
DR   SMR; Q57604; -.
DR   STRING; 243232.MJ_0138.1; -.
DR   TCDB; 1.A.1.13.8; the voltage-gated ion channel (vic) superfamily.
DR   PRIDE; Q57604; -.
DR   EnsemblBacteria; AAB98130; AAB98130; MJ_0138.1.
DR   GeneID; 1450981; -.
DR   KEGG; mja:MJ_0138.1; -.
DR   eggNOG; arCOG01958; Archaea.
DR   HOGENOM; CLU_050982_0_1_2; -.
DR   InParanoid; Q57604; -.
DR   OMA; VFEGIWW; -.
DR   OrthoDB; 80000at2157; -.
DR   PhylomeDB; Q57604; -.
DR   Proteomes; UP000000805; Chromosome.
DR   GO; GO:0016021; C:integral component of membrane; IEA:UniProtKB-KW.
DR   GO; GO:0005886; C:plasma membrane; IEA:UniProtKB-SubCell.
DR   GO; GO:0005267; F:potassium channel activity; IEA:UniProtKB-KW.
DR   Gene3D; 3.30.70.1450; -; 1.
DR   InterPro; IPR003280; 2pore_dom_K_chnl.
DR   InterPro; IPR013099; K_chnl_dom.
DR   InterPro; IPR036291; NAD(P)-bd_dom_sf.
DR   InterPro; IPR006037; RCK_C.
DR   InterPro; IPR036721; RCK_C_sf.
DR   InterPro; IPR003148; RCK_N.
DR   Pfam; PF07885; Ion_trans_2; 1.
DR   Pfam; PF02080; TrkA_C; 1.
DR   Pfam; PF02254; TrkA_N; 1.
DR   PRINTS; PR01333; 2POREKCHANEL.
DR   SUPFAM; SSF116726; SSF116726; 1.
DR   SUPFAM; SSF51735; SSF51735; 1.
DR   PROSITE; PS51202; RCK_C; 1.
DR   PROSITE; PS51201; RCK_N; 1.
PE   4: Predicted;
KW   Cell membrane; Ion channel; Ion transport; Membrane; Potassium;
KW   Potassium channel; Potassium transport; Reference proteome; Transmembrane;
KW   Transmembrane helix; Transport.
FT   CHAIN           1..333
FT                   /note="Potassium channel protein 1"
FT                   /id="PRO_0000054099"
FT   TOPO_DOM        1..6
FT                   /note="Cytoplasmic"
FT                   /evidence="ECO:0000255"
FT   TRANSMEM        7..27
FT                   /note="Helical"
FT                   /evidence="ECO:0000255"
FT   TOPO_DOM        28..60
FT                   /note="Extracellular"
FT                   /evidence="ECO:0000255"
FT   TRANSMEM        61..81
FT                   /note="Helical"
FT                   /evidence="ECO:0000255"
FT   TOPO_DOM        82..333
FT                   /note="Cytoplasmic"
FT                   /evidence="ECO:0000255"
FT   DOMAIN          109..233
FT                   /note="RCK N-terminal"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00543"
FT   DOMAIN          246..331
FT                   /note="RCK C-terminal"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00544"
FT   MOTIF           46..51
FT                   /note="Selectivity filter"
FT                   /evidence="ECO:0000250"
SQ   SEQUENCE   333 AA;  37150 MW;  7CC082675F96B06A CRC64;
     METYEKIELG IIVIILLILI ESVILMTVEG WDFFTAFYTA VVTISTVGYG DYTPQTFLGK
     LSVIIYIFAG VGAVAYTMGN IASFFIEGHF RKYFRLRKMM DRIKKLNNHY IICGYGRLGK
     VIAEEFKKCN IPFVIIDSDE KLLEEALEKD PNLICIVGDA TSDDILKKAK IEKAKGLISV
     VSSDAENVFI TLSAKKLNPN IYIVAKAEKP STLDKLIKAG ADRAVCPYIV GGMEIARIAI
     NPDIVEFIHS LVATEEDMEV RRYIVKNKEL DNKLLKDSGI REKTGATILA VKKGDKTITS
     PPPDTVINIG DIIYAFGTKE QLEKLKRYVE GVE