ID   PEPB_CANLF              Reviewed;         390 AA.
AC   Q8SQ41;
DT   16-AUG-2005, integrated into UniProtKB/Swiss-Prot.
DT   01-JUN-2002, sequence version 1.
DT   03-AUG-2022, entry version 97.
DE   RecName: Full=Pepsin B;
DE            EC=3.4.23.2 {ECO:0000269|PubMed:12147255};
DE   Flags: Precursor;
GN   Name=PGB; Synonyms=PGNB;
OS   Canis lupus familiaris (Dog) (Canis familiaris).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC   Eutheria; Laurasiatheria; Carnivora; Caniformia; Canidae; Canis.
OX   NCBI_TaxID=9615;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, CATALYTIC ACTIVITY, AND
RP   CHARACTERIZATION.
RX   PubMed=12147255; DOI=10.1016/s0003-9861(02)00209-6;
RA   Narita Y., Oda S., Moriyama A., Kageyama T.;
RT   "Primary structure, unique enzymatic properties, and molecular evolution of
RT   pepsinogen B and pepsin B.";
RL   Arch. Biochem. Biophys. 404:177-185(2002).
CC   -!- FUNCTION: Hydrolyzes various peptides including beta-endorphin, insulin
CC       B chain, dynorphin A, and neurokinin A, with high specificity for the
CC       cleavage of the Phe-Xaa bonds. {ECO:0000269|PubMed:12147255}.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=Degradation of gelatin, little activity on hemoglobin.
CC         Specificity on B chain of insulin more restricted than that of pepsin
CC         A. Does not cleave 1-Phe-|-Val-2, 4-Gln-|-His-5 or 23-Gly-|-Phe-24.;
CC         EC=3.4.23.2; Evidence={ECO:0000269|PubMed:12147255};
CC   -!- SUBCELLULAR LOCATION: Secreted.
CC   -!- SIMILARITY: Belongs to the peptidase A1 family. {ECO:0000305}.
CC   ---------------------------------------------------------------------------
CC   Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC   Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC   ---------------------------------------------------------------------------
DR   EMBL; AB082936; BAB86888.1; -; mRNA.
DR   RefSeq; NP_001003028.1; NM_001003028.1.
DR   AlphaFoldDB; Q8SQ41; -.
DR   SMR; Q8SQ41; -.
DR   STRING; 9612.ENSCAFP00000029216; -.
DR   MEROPS; A01.002; -.
DR   PaxDb; Q8SQ41; -.
DR   GeneID; 403552; -.
DR   KEGG; cfa:403552; -.
DR   CTD; 403552; -.
DR   eggNOG; KOG1339; Eukaryota.
DR   InParanoid; Q8SQ41; -.
DR   OrthoDB; 1619495at2759; -.
DR   Proteomes; UP000002254; Unplaced.
DR   GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR   GO; GO:0004190; F:aspartic-type endopeptidase activity; IEA:UniProtKB-KW.
DR   GO; GO:0007586; P:digestion; IEA:UniProtKB-KW.
DR   GO; GO:0006508; P:proteolysis; IEA:UniProtKB-KW.
DR   Gene3D; 2.40.70.10; -; 2.
DR   InterPro; IPR001461; Aspartic_peptidase_A1.
DR   InterPro; IPR001969; Aspartic_peptidase_AS.
DR   InterPro; IPR012848; Aspartic_peptidase_N.
DR   InterPro; IPR033121; PEPTIDASE_A1.
DR   InterPro; IPR021109; Peptidase_aspartic_dom_sf.
DR   PANTHER; PTHR47966; PTHR47966; 1.
DR   Pfam; PF07966; A1_Propeptide; 1.
DR   Pfam; PF00026; Asp; 1.
DR   PRINTS; PR00792; PEPSIN.
DR   SUPFAM; SSF50630; SSF50630; 1.
DR   PROSITE; PS00141; ASP_PROTEASE; 1.
DR   PROSITE; PS51767; PEPTIDASE_A1; 1.
PE   1: Evidence at protein level;
KW   Aspartyl protease; Digestion; Disulfide bond; Hydrolase; Protease;
KW   Reference proteome; Secreted; Signal; Zymogen.
FT   SIGNAL          1..16
FT                   /evidence="ECO:0000255"
FT   PROPEP          17..59
FT                   /note="Activation peptide"
FT                   /id="PRO_0000026048"
FT   CHAIN           60..390
FT                   /note="Pepsin B"
FT                   /id="PRO_0000026049"
FT   DOMAIN          74..387
FT                   /note="Peptidase A1"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU01103"
FT   ACT_SITE        92
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU10094"
FT   ACT_SITE        278
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU10094"
FT   DISULFID        105..110
FT                   /evidence="ECO:0000250"
FT   DISULFID        269..273
FT                   /evidence="ECO:0000250"
FT   DISULFID        312..345
FT                   /evidence="ECO:0000250"
SQ   SEQUENCE   390 AA;  43497 MW;  0AE3F4C05A7FC662 CRC64;
     MKIQVLVLVC LHLSEGVERI ILKKGKSIRQ VMEERGVLET FLRNHPKVDP AAKYLFNNDA
     VAYEPFTNYL DSYYFGEISI GTPPQNFLIL FDTGSSNLWV PSTYCQSQAC SNHNRFNPSR
     SSTYQSSEQT YTLAYGFGSL TVLLGYDTVT VQNIVIHNQL FGMSENEPNY PFYYSYFDGI
     LGMAYSNLAV DNGPTVLQNM MQQGQLTQPI FSFYFSPQPT YEYGGELILG GVDTQFYSGE
     IVWAPVTREM YWQVAIDEFL IGNQATGLCS QGCQGIVDTG TFPLTVPQQY LDSFVKATGA
     QQDQSGNFVV NCNSIQSMPT ITFVISGSPL PLPPSTYVLN NNGYCTLGIE VTYLPSPNGQ
     PLWILGDVFL REYYTVFDMA ANRVGFALSS