ID   NAPA_ENTHR              Reviewed;         383 AA.
AC   P26235;
DT   01-MAY-1992, integrated into UniProtKB/Swiss-Prot.
DT   01-MAY-1992, sequence version 1.
DT   25-MAY-2022, entry version 90.
DE   RecName: Full=Na(+)/H(+) antiporter;
GN   Name=napA;
OS   Enterococcus hirae.
OC   Bacteria; Firmicutes; Bacilli; Lactobacillales; Enterococcaceae;
OC   Enterococcus.
OX   NCBI_TaxID=1354;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA], FUNCTION, SUBCELLULAR LOCATION, AND GENE
RP   NAME.
RX   PubMed=1312090; DOI=10.1016/s0021-9258(18)42779-2;
RA   Waser M., Hess-Bienz D., Davies K., Solioz M.;
RT   "Cloning and disruption of a putative NaH-antiporter gene of Enterococcus
RT   hirae.";
RL   J. Biol. Chem. 267:5396-5400(1992).
RN   [2]
RP   SIMILARITY TO KEFC.
RX   PubMed=1325937; DOI=10.1016/0378-1097(92)90601-j;
RA   Reizer J., Reizer A., Saier M.H. Jr.;
RT   "The putative Na+/H+ antiporter (NapA) of Enterococcus hirae is homologous
RT   to the putative K+/H+ antiporter (KefC) of Escherichia coli.";
RL   FEMS Microbiol. Lett. 73:161-163(1992).
RN   [3]
RP   FUNCTION, BIOPHYSICOCHEMICAL PROPERTIES, AND SUBCELLULAR LOCATION.
RX   PubMed=8253756; DOI=10.1016/s0021-9258(19)74319-1;
RA   Strausak D., Waser M., Solioz M.;
RT   "Functional expression of the Enterococcus hirae NaH-antiporter in
RT   Escherichia coli.";
RL   J. Biol. Chem. 268:26334-26337(1993).
CC   -!- FUNCTION: Na(+)/H(+) antiporter that extrudes sodium in exchange for
CC       external protons. Can also transport lithium.
CC       {ECO:0000269|PubMed:1312090, ECO:0000269|PubMed:8253756}.
CC   -!- BIOPHYSICOCHEMICAL PROPERTIES:
CC       Kinetic parameters:
CC         KM=1 mM for sodium {ECO:0000269|PubMed:8253756};
CC         KM=0.1 mM for lithium {ECO:0000269|PubMed:8253756};
CC   -!- SUBCELLULAR LOCATION: Cell membrane {ECO:0000269|PubMed:1312090,
CC       ECO:0000269|PubMed:8253756}; Multi-pass membrane protein
CC       {ECO:0000269|PubMed:1312090, ECO:0000269|PubMed:8253756}.
CC   -!- SIMILARITY: Belongs to the monovalent cation:proton antiporter 2 (CPA2)
CC       transporter (TC 2.A.37) family. {ECO:0000305}.
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DR   EMBL; M81961; AAA24781.1; -; Genomic_DNA.
DR   PIR; A42111; A42111.
DR   RefSeq; WP_010737630.1; NZ_MJDO01000027.1.
DR   AlphaFoldDB; P26235; -.
DR   SMR; P26235; -.
DR   STRING; 1354.A6P53_06565; -.
DR   TCDB; 2.A.37.2.1; the monovalent cation:proton antiporter-2 (cpa2) family.
DR   PATRIC; fig|1354.25.peg.1787; -.
DR   GO; GO:0016021; C:integral component of membrane; IDA:UniProtKB.
DR   GO; GO:0005886; C:plasma membrane; IEA:UniProtKB-SubCell.
DR   GO; GO:0015297; F:antiporter activity; IDA:UniProtKB.
DR   GO; GO:0015081; F:sodium ion transmembrane transporter activity; IDA:UniProtKB.
DR   GO; GO:0015299; F:solute:proton antiporter activity; IEA:InterPro.
DR   GO; GO:0035725; P:sodium ion transmembrane transport; IDA:UniProtKB.
DR   Gene3D; 1.20.1530.20; -; 1.
DR   InterPro; IPR006153; Cation/H_exchanger.
DR   InterPro; IPR004771; K/H_exchanger.
DR   InterPro; IPR038770; Na+/solute_symporter_sf.
DR   Pfam; PF00999; Na_H_Exchanger; 1.
DR   TIGRFAMs; TIGR00932; 2a37; 1.
PE   1: Evidence at protein level;
KW   Antiport; Cell membrane; Ion transport; Membrane; Sodium; Sodium transport;
KW   Transmembrane; Transmembrane helix; Transport.
FT   CHAIN           1..383
FT                   /note="Na(+)/H(+) antiporter"
FT                   /id="PRO_0000196615"
FT   TRANSMEM        1..21
FT                   /note="Helical"
FT                   /evidence="ECO:0000255"
FT   TRANSMEM        24..44
FT                   /note="Helical"
FT                   /evidence="ECO:0000255"
FT   TRANSMEM        51..71
FT                   /note="Helical"
FT                   /evidence="ECO:0000255"
FT   TRANSMEM        83..103
FT                   /note="Helical"
FT                   /evidence="ECO:0000255"
FT   TRANSMEM        112..132
FT                   /note="Helical"
FT                   /evidence="ECO:0000255"
FT   TRANSMEM        145..165
FT                   /note="Helical"
FT                   /evidence="ECO:0000255"
FT   TRANSMEM        186..206
FT                   /note="Helical"
FT                   /evidence="ECO:0000255"
FT   TRANSMEM        216..236
FT                   /note="Helical"
FT                   /evidence="ECO:0000255"
FT   TRANSMEM        262..282
FT                   /note="Helical"
FT                   /evidence="ECO:0000255"
FT   TRANSMEM        291..311
FT                   /note="Helical"
FT                   /evidence="ECO:0000255"
FT   TRANSMEM        323..343
FT                   /note="Helical"
FT                   /evidence="ECO:0000255"
FT   TRANSMEM        353..373
FT                   /note="Helical"
FT                   /evidence="ECO:0000255"
SQ   SEQUENCE   383 AA;  41555 MW;  C21E6A150EBB692C CRC64;
     MEFIGILCLI LVATTIGSHI SRRFGIPAVI GQLLVGVLLG QAGLGWVHPN ILVHDFSEIG
     VILLMFLAGL ESDLSLLKKY FKPGMFVALL GILFPVFFGW LTGEAFQVAN NEAIFFGIIL
     AATSVSISVE VLKELNVVNT KEGSTILGAS VVDDILVVLV LSFSLSFLTG KSTSNLPLPL
     LLLEQLFYFL FIFLLVKWIA PFLMSLAEKI YANSAIIIMS LVICLGMSYL ADLIGLSSVI
     GAFFAGIAVS QTKVKHEVYN NVEALGYAVF IPVFFVSVGL EVDFSKFSEQ ILFILILTLV
     AILTKLIGGY IGAKFSSFSS NSALMVGAGM ISRGEMALII LQIGQQSNLI ENHYYSPLVI
     VVLLSTLISP LILKYFTKKV YAN