ID   HEM2_CHLRE              Reviewed;         390 AA.
AC   Q42682;
DT   01-NOV-1997, integrated into UniProtKB/Swiss-Prot.
DT   01-NOV-1997, sequence version 1.
DT   03-AUG-2022, entry version 96.
DE   RecName: Full=Delta-aminolevulinic acid dehydratase, chloroplastic;
DE            Short=ALADH;
DE            EC=4.2.1.24;
DE   AltName: Full=Porphobilinogen synthase;
DE   Flags: Precursor;
GN   Name=HEMB; Synonyms=ALAD;
OS   Chlamydomonas reinhardtii (Chlamydomonas smithii).
OC   Eukaryota; Viridiplantae; Chlorophyta; core chlorophytes; Chlorophyceae;
OC   CS clade; Chlamydomonadales; Chlamydomonadaceae; Chlamydomonas.
OX   NCBI_TaxID=3055;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA].
RC   STRAIN=NO-;
RX   PubMed=7894023; DOI=10.1007/bf00019326;
RA   Matters G.L., Beale S.I.;
RT   "Structure and expression of the Chlamydomonas reinhardtii alad gene
RT   encoding the chlorophyll biosynthetic enzyme, delta-aminolevulinic acid
RT   dehydratase (porphobilinogen synthase).";
RL   Plant Mol. Biol. 27:607-617(1995).
CC   -!- FUNCTION: Catalyzes an early step in the biosynthesis of tetrapyrroles.
CC       Binds two molecules of 5-aminolevulinate per subunit, each at a
CC       distinct site, and catalyzes their condensation to form porphobilinogen
CC       (By similarity). {ECO:0000250}.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=2 5-aminolevulinate = H(+) + 2 H2O + porphobilinogen;
CC         Xref=Rhea:RHEA:24064, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378,
CC         ChEBI:CHEBI:58126, ChEBI:CHEBI:356416; EC=4.2.1.24;
CC   -!- COFACTOR:
CC       Name=Mg(2+); Xref=ChEBI:CHEBI:18420; Evidence={ECO:0000250};
CC       Note=Binds 2 magnesium ions per monomer. The first magnesium ion is
CC       required for catalysis. The second functions as allosteric activator.
CC       {ECO:0000250};
CC   -!- PATHWAY: Porphyrin-containing compound metabolism; protoporphyrin-IX
CC       biosynthesis; coproporphyrinogen-III from 5-aminolevulinate: step 1/4.
CC   -!- SUBUNIT: Homooctamer. {ECO:0000250}.
CC   -!- SUBCELLULAR LOCATION: Plastid, chloroplast.
CC   -!- SIMILARITY: Belongs to the ALAD 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; U19876; AAA79515.1; -; mRNA.
DR   PIR; S53487; S53487.
DR   AlphaFoldDB; Q42682; -.
DR   SMR; Q42682; -.
DR   STRING; 3055.EDP06754; -.
DR   ProMEX; Q42682; -.
DR   eggNOG; KOG2794; Eukaryota.
DR   UniPathway; UPA00251; UER00318.
DR   GO; GO:0009507; C:chloroplast; IEA:UniProtKB-SubCell.
DR   GO; GO:0046872; F:metal ion binding; IEA:UniProtKB-KW.
DR   GO; GO:0004655; F:porphobilinogen synthase activity; IEA:UniProtKB-EC.
DR   GO; GO:0015995; P:chlorophyll biosynthetic process; IEA:UniProtKB-KW.
DR   GO; GO:0006782; P:protoporphyrinogen IX biosynthetic process; IEA:UniProtKB-UniPathway.
DR   Gene3D; 3.20.20.70; -; 1.
DR   InterPro; IPR001731; ALAD.
DR   InterPro; IPR030656; ALAD_AS.
DR   InterPro; IPR013785; Aldolase_TIM.
DR   PANTHER; PTHR11458; PTHR11458; 1.
DR   Pfam; PF00490; ALAD; 1.
DR   PRINTS; PR00144; DALDHYDRTASE.
DR   SMART; SM01004; ALAD; 1.
DR   PROSITE; PS00169; D_ALA_DEHYDRATASE; 1.
PE   2: Evidence at transcript level;
KW   Allosteric enzyme; Chlorophyll biosynthesis; Chloroplast;
KW   Heme biosynthesis; Lyase; Magnesium; Metal-binding; Plastid;
KW   Porphyrin biosynthesis; Transit peptide.
FT   TRANSIT         1..24
FT                   /note="Chloroplast"
FT                   /evidence="ECO:0000255"
FT   CHAIN           25..390
FT                   /note="Delta-aminolevulinic acid dehydratase,
FT                   chloroplastic"
FT                   /id="PRO_0000013315"
FT   REGION          34..69
FT                   /note="Disordered"
FT                   /evidence="ECO:0000256|SAM:MobiDB-lite"
FT   ACT_SITE        251
FT                   /note="Schiff-base intermediate with substrate"
FT                   /evidence="ECO:0000250"
FT   ACT_SITE        312
FT                   /note="Schiff-base intermediate with substrate"
FT                   /evidence="ECO:0000250"
FT   BINDING         261
FT                   /ligand="5-aminolevulinate"
FT                   /ligand_id="ChEBI:CHEBI:356416"
FT                   /ligand_label="1"
FT                   /evidence="ECO:0000250"
FT   BINDING         281
FT                   /ligand="5-aminolevulinate"
FT                   /ligand_id="ChEBI:CHEBI:356416"
FT                   /ligand_label="1"
FT                   /evidence="ECO:0000250"
FT   BINDING         297
FT                   /ligand="Mg(2+)"
FT                   /ligand_id="ChEBI:CHEBI:18420"
FT                   /evidence="ECO:0000250"
FT   BINDING         338
FT                   /ligand="5-aminolevulinate"
FT                   /ligand_id="ChEBI:CHEBI:356416"
FT                   /ligand_label="2"
FT                   /evidence="ECO:0000250"
FT   BINDING         377
FT                   /ligand="5-aminolevulinate"
FT                   /ligand_id="ChEBI:CHEBI:356416"
FT                   /ligand_label="2"
FT                   /evidence="ECO:0000250"
SQ   SEQUENCE   390 AA;  43046 MW;  6114C4E0325A4242 CRC64;
     MQMMQRNVVG QRPVAGSRRS LVVANVAEVT RPAVSTNGKH RTGVPEGTPI VTPQDLPSRP
     RRNRRSESFR ASVREVNVSP ANFILPIFIH EESNQNVPIA SMPGINRLAY GKNVIDYVAE
     PRSYGVNQVV VFPKTPDHLK TQTAEEAFNK NGLSQRTIRL LKDSFPDLEV YTDVALDPYN
     SDGHDGIVSD AGVILNDETI EYLCRQAVSQ AEAGADVVSP SDMMDGRVGA IRRALDREGF
     TNVSIMSYTA KYASAYYGPF RDALASAPKP GQAHRRIPPN KKTYQMDPAN YREAIREAKA
     DEAEGADIMM VKPGMPYLDV VRLLRETSPL PVAVYHVSGE YAMLKAAAER GWLNEKDAVL
     EAMTCFRRAG GDLILTYYGI EASKWLAGEK