ID   DCAM_SPIOL              Reviewed;         363 AA.
AC   P46255;
DT   01-NOV-1995, integrated into UniProtKB/Swiss-Prot.
DT   01-NOV-1995, sequence version 1.
DT   25-MAY-2022, entry version 90.
DE   RecName: Full=S-adenosylmethionine decarboxylase proenzyme;
DE            Short=AdoMetDC;
DE            Short=SAMDC;
DE            EC=4.1.1.50;
DE   Contains:
DE     RecName: Full=S-adenosylmethionine decarboxylase alpha chain;
DE   Contains:
DE     RecName: Full=S-adenosylmethionine decarboxylase beta chain;
DE   Flags: Precursor;
GN   Name=SAMDC;
OS   Spinacia oleracea (Spinach).
OC   Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta;
OC   Spermatophyta; Magnoliopsida; eudicotyledons; Gunneridae; Pentapetalae;
OC   Caryophyllales; Chenopodiaceae; Chenopodioideae; Anserineae; Spinacia.
OX   NCBI_TaxID=3562;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA].
RC   STRAIN=cv. Monatol;
RX   PubMed=7770535; DOI=10.1104/pp.107.4.1461;
RA   Bolle C., Herrmann R.G., Oelmueller R.;
RT   "A spinach cDNA with homology to S-Adenosylmethionine decarboxylase.";
RL   Plant Physiol. 107:1461-1462(1995).
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=H(+) + S-adenosyl-L-methionine = CO2 + S-adenosyl 3-
CC         (methylsulfanyl)propylamine; Xref=Rhea:RHEA:15981, ChEBI:CHEBI:15378,
CC         ChEBI:CHEBI:16526, ChEBI:CHEBI:57443, ChEBI:CHEBI:59789; EC=4.1.1.50;
CC   -!- COFACTOR:
CC       Name=pyruvate; Xref=ChEBI:CHEBI:15361; Evidence={ECO:0000250};
CC       Note=Binds 1 pyruvoyl group covalently per subunit. {ECO:0000250};
CC   -!- PATHWAY: Amine and polyamine biosynthesis; S-adenosylmethioninamine
CC       biosynthesis; S-adenosylmethioninamine from S-adenosyl-L-methionine:
CC       step 1/1.
CC   -!- PTM: Is synthesized initially as an inactive proenzyme. Formation of
CC       the active enzyme involves a self-maturation process in which the
CC       active site pyruvoyl group is generated from an internal serine residue
CC       via an autocatalytic post-translational modification. Two non-identical
CC       subunits are generated from the proenzyme in this reaction, and the
CC       pyruvate is formed at the N-terminus of the alpha chain, which is
CC       derived from the carboxyl end of the proenzyme. The post-translation
CC       cleavage follows an unusual pathway, termed non-hydrolytic serinolysis,
CC       in which the side chain hydroxyl group of the serine supplies its
CC       oxygen atom to form the C-terminus of the beta chain, while the
CC       remainder of the serine residue undergoes an oxidative deamination to
CC       produce ammonia and the pyruvoyl group blocking the N-terminus of the
CC       alpha chain (By similarity). {ECO:0000250}.
CC   -!- SIMILARITY: Belongs to the eukaryotic AdoMetDC family. {ECO:0000305}.
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DR   EMBL; X81414; CAA57170.1; -; mRNA.
DR   PIR; S49222; S49222.
DR   AlphaFoldDB; P46255; -.
DR   SMR; P46255; -.
DR   UniPathway; UPA00331; UER00451.
DR   GO; GO:0004014; F:adenosylmethionine decarboxylase activity; IEA:UniProtKB-EC.
DR   GO; GO:0006557; P:S-adenosylmethioninamine biosynthetic process; IEA:UniProtKB-UniPathway.
DR   GO; GO:0008295; P:spermidine biosynthetic process; IEA:UniProtKB-KW.
DR   GO; GO:0006597; P:spermine biosynthetic process; IEA:InterPro.
DR   InterPro; IPR001985; S-AdoMet_decarboxylase.
DR   InterPro; IPR016067; S-AdoMet_deCO2ase_core.
DR   InterPro; IPR018166; S-AdoMet_deCO2ase_CS.
DR   PANTHER; PTHR11570; PTHR11570; 1.
DR   Pfam; PF01536; SAM_decarbox; 1.
DR   PIRSF; PIRSF001355; S-AdenosylMet_decarboxylase; 1.
DR   SUPFAM; SSF56276; SSF56276; 1.
DR   TIGRFAMs; TIGR00535; SAM_DCase; 1.
DR   PROSITE; PS01336; ADOMETDC; 1.
PE   2: Evidence at transcript level;
KW   Autocatalytic cleavage; Decarboxylase; Lyase; Polyamine biosynthesis;
KW   Pyruvate; S-adenosyl-L-methionine; Schiff base; Spermidine biosynthesis;
KW   Zymogen.
FT   CHAIN           1..68
FT                   /note="S-adenosylmethionine decarboxylase beta chain"
FT                   /evidence="ECO:0000250"
FT                   /id="PRO_0000030025"
FT   CHAIN           69..363
FT                   /note="S-adenosylmethionine decarboxylase alpha chain"
FT                   /evidence="ECO:0000250"
FT                   /id="PRO_0000030026"
FT   ACT_SITE        9
FT                   /evidence="ECO:0000250"
FT   ACT_SITE        12
FT                   /evidence="ECO:0000250"
FT   ACT_SITE        69
FT                   /note="Schiff-base intermediate with substrate; via pyruvic
FT                   acid"
FT                   /evidence="ECO:0000250"
FT   ACT_SITE        83
FT                   /note="Proton donor; for catalytic activity"
FT                   /evidence="ECO:0000250"
FT   ACT_SITE        232
FT                   /note="Proton acceptor; for processing activity"
FT                   /evidence="ECO:0000250"
FT   ACT_SITE        245
FT                   /note="Proton acceptor; for processing activity"
FT                   /evidence="ECO:0000250"
FT   SITE            68..69
FT                   /note="Cleavage (non-hydrolytic); by autolysis"
FT                   /evidence="ECO:0000250"
FT   MOD_RES         69
FT                   /note="Pyruvic acid (Ser); by autocatalysis"
FT                   /evidence="ECO:0000250"
SQ   SEQUENCE   363 AA;  39960 MW;  CE4D6DDE4E8A3220 CRC64;
     MAISAIGFEG FEKRLEITFF EPSIFVDPEG KGLRALCKAQ LDEILGPAEC TIVDSLANES
     VDSYVLSESS LFIYAYKIII KTCGTTKLLR AIPPILRLAG KLSLDVKSVR YTRGSFIFPG
     AQSYAHRSFS EEVAVLDGYF GKLAAGSKAF VMGDPAKPQK WHVYSASAET ISFEEPVYTL
     EMCMTGLKKE KASVFFKSQS PNAAVMTESS GIRKILPDSK ICDFDFEPCG YSMNAIEGPA
     ISTIHITPED GFSYASFEAV GYDLKKTDLN QLVERVLACF EPSEFSIAIH AEIAANSMEH
     NCYVNVNGYS REEGGIEELG FGAASVFYQK FCKASTGFGA TNKPKPALKC CWKEDKFEEE
     KDY