KA171_MESMA
ID KA171_MESMA Reviewed; 55 AA.
AC Q95NJ8; Q3L666;
DT 26-SEP-2003, integrated into UniProtKB/Swiss-Prot.
DT 01-DEC-2001, sequence version 1.
DT 25-MAY-2022, entry version 85.
DE RecName: Full=Potassium channel toxin alpha-KTx 17.1;
DE AltName: Full=BmKK4;
DE AltName: Full=Toxin Kk4;
DE AltName: Full=Toxin TXKs4;
DE Flags: Precursor;
OS Mesobuthus martensii (Manchurian scorpion) (Buthus martensii).
OC Eukaryota; Metazoa; Ecdysozoa; Arthropoda; Chelicerata; Arachnida;
OC Scorpiones; Buthida; Buthoidea; Buthidae; Mesobuthus.
OX NCBI_TaxID=34649;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA].
RC TISSUE=Venom gland;
RX PubMed=11698110; DOI=10.1016/s0300-9084(01)01326-8;
RA Zeng X.-C., Peng F., Luo F., Zhu S.-Y., Liu H., Li W.-X.;
RT "Molecular cloning and characterization of four scorpion K(+)-toxin-like
RT peptides: a new subfamily of venom peptides (alpha-KTx14) and genomic
RT analysis of a member.";
RL Biochimie 83:883-889(2001).
RN [2]
RP NUCLEOTIDE SEQUENCE [MRNA].
RC TISSUE=Venom gland;
RA Zhu S.-Y., Li W.-X.;
RT "Full-length cDNA encoding a putative K+ channel blocker from BmK.";
RL Submitted (JUN-1999) to the EMBL/GenBank/DDBJ databases.
RN [3]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RA Luo F., Li W.X., Zeng X.C.;
RL Submitted (JUN-2004) to the EMBL/GenBank/DDBJ databases.
RN [4]
RP PROTEIN SEQUENCE OF 24-55, FUNCTION, AND AMIDATION AT THR-53.
RC TISSUE=Venom;
RX PubMed=12906891; DOI=10.1016/s0041-0101(03)00136-3;
RA Li M.-H., Zhang N.-X., Chen X.-Q., Wu G., Wu H.-M., Hu G.-Y.;
RT "BmKK4, a novel toxin from the venom of Asian scorpion Buthus martensi
RT Karsch, inhibits potassium currents in rat hippocampal neurons in vitro.";
RL Toxicon 42:199-205(2003).
RN [5]
RP STRUCTURE BY NMR OF 24-53, PYROGLUTAMATE FORMATION AT GLN-24, AND DISULFIDE
RP BONDS.
RX PubMed=15449936; DOI=10.1021/bi0490643;
RA Zhang N.-X., Chen X., Li M.-H., Cao C., Wang Y., Wu G., Hu G.-Y., Wu H.-M.;
RT "Solution structure of BmKK4, the first member of subfamily alpha-KTx 17 of
RT scorpion toxins.";
RL Biochemistry 43:12469-12476(2004).
CC -!- FUNCTION: Blocker of potassium channels, which inhibits both the
CC delayed rectifier and fast transient potassium current. The inhibition
CC is reversible and voltage-independent. It causes a depolarizing shift
CC of the steady-state activation curve of the currents, without changing
CC their steady-state inactivation behavior.
CC {ECO:0000269|PubMed:12906891}.
CC -!- SUBCELLULAR LOCATION: Secreted.
CC -!- TISSUE SPECIFICITY: Expressed by the venom gland.
CC -!- DOMAIN: Has the structural arrangement of an alpha-helix connected to a
CC beta-sheet by disulfide bonds (CSalpha/beta).
CC -!- SIMILARITY: Belongs to the short scorpion toxin superfamily. Potassium
CC channel inhibitor family. Alpha-KTx 17 subfamily. {ECO:0000305}.
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DR EMBL; AJ277729; CAC38038.1; -; mRNA.
DR EMBL; AF159974; AAK61821.1; -; mRNA.
DR EMBL; AY647145; AAV59462.1; -; Genomic_DNA.
DR PDB; 1S8K; NMR; -; A=24-53.
DR PDBsum; 1S8K; -.
DR AlphaFoldDB; Q95NJ8; -.
DR BMRB; Q95NJ8; -.
DR SMR; Q95NJ8; -.
DR EvolutionaryTrace; Q95NJ8; -.
DR GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR GO; GO:0015459; F:potassium channel regulator activity; IEA:UniProtKB-KW.
DR GO; GO:0090729; F:toxin activity; IEA:UniProtKB-KW.
PE 1: Evidence at protein level;
KW 3D-structure; Amidation; Direct protein sequencing; Disulfide bond;
KW Ion channel impairing toxin; Neurotoxin; Potassium channel impairing toxin;
KW Pyrrolidone carboxylic acid; Secreted; Signal; Toxin.
FT SIGNAL 1..23
FT /evidence="ECO:0000269|PubMed:12906891"
FT PEPTIDE 24..53
FT /note="Potassium channel toxin alpha-KTx 17.1"
FT /id="PRO_0000035336"
FT MOD_RES 24
FT /note="Pyrrolidone carboxylic acid"
FT /evidence="ECO:0000269|PubMed:15449936"
FT MOD_RES 53
FT /note="Threonine amide"
FT /evidence="ECO:0000269|PubMed:12906891"
FT DISULFID 27..43
FT /evidence="ECO:0000269|PubMed:15449936"
FT DISULFID 33..48
FT /evidence="ECO:0000269|PubMed:15449936"
FT DISULFID 37..50
FT /evidence="ECO:0000269|PubMed:15449936"
FT CONFLICT 13
FT /note="L -> F (in Ref. 2; AAV59462)"
FT /evidence="ECO:0000305"
FT CONFLICT 54
FT /note="G -> R (in Ref. 2; AAV59462)"
FT /evidence="ECO:0000305"
FT HELIX 30..36
FT /evidence="ECO:0007829|PDB:1S8K"
FT STRAND 38..44
FT /evidence="ECO:0007829|PDB:1S8K"
FT STRAND 47..51
FT /evidence="ECO:0007829|PDB:1S8K"
SQ SEQUENCE 55 AA; 6161 MW; BF0E5B205BED9FC7 CRC64;
MKFIIVLILI SVLIATIVPV NEAQTQCQSV RDCQQYCLTP DRCSYGTCYC KTTGK
