AC   MF_00420;
DC   Protein; auto
TR   HAMAP; MF_00420; -; 1; level=0
XX
Names: PurL_2
XX
ID   PURL
DE   RecName: Full=Phosphoribosylformylglycinamidine synthase subunit PurL;
DE            Short=FGAM synthase;
DE            EC=6.3.5.3;
DE   AltName: Full=Formylglycinamide ribonucleotide amidotransferase subunit II;
DE            Short=FGAR amidotransferase II;
DE            Short=FGAR-AT II;
DE   AltName: Full=Phosphoribosylformylglycinamidine synthase subunit II;
DE   AltName: Full=Glutamine amidotransferase PurL;
GN   Name=purL;
XX
CC   -!- FUNCTION: Part of the phosphoribosylformylglycinamidine synthase
CC       complex involved in the purines biosynthetic pathway. Catalyzes the
CC       ATP-dependent conversion of formylglycinamide ribonucleotide (FGAR) and
CC       glutamine to yield formylglycinamidine ribonucleotide (FGAM) and
CC       glutamate. The FGAM synthase complex is composed of three subunits.
CC       PurQ produces an ammonia molecule by converting glutamine to glutamate.
CC       PurL transfers the ammonia molecule to FGAR to form FGAM in an ATP-
CC       dependent manner. PurS interacts with PurQ and PurL and is thought to
CC       assist in the transfer of the ammonia molecule from PurQ to PurL.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=ATP + H2O + L-glutamine + N(2)-formyl-N(1)-(5-phospho-beta-D-
CC         ribosyl)glycinamide = 2-formamido-N(1)-(5-O-phospho-beta-D-
CC         ribosyl)acetamidine + ADP + H(+) + L-glutamate + phosphate;
CC         Xref=Rhea:RHEA:17129, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378,
CC         ChEBI:CHEBI:29985, ChEBI:CHEBI:30616, ChEBI:CHEBI:43474,
CC         ChEBI:CHEBI:58359, ChEBI:CHEBI:147286, ChEBI:CHEBI:147287,
CC         ChEBI:CHEBI:456216; EC=6.3.5.3;
CC   -!- PATHWAY: Purine metabolism; IMP biosynthesis via de novo pathway; 5-
CC       amino-1-(5-phospho-D-ribosyl)imidazole from N(2)-formyl-N(1)-(5-
CC       phospho-D-ribosyl)glycinamide: step 1/2.
CC   -!- SUBUNIT: Monomer. Part of the FGAM synthase complex composed of 1 PurL,
CC       1 PurQ and 2 PurS subunits.
CC   -!- SUBCELLULAR LOCATION: Cytoplasm.
CC   -!- SIMILARITY: Belongs to the FGAMS family.
XX
DR   Pfam; PF00586; AIRS; 1; trigger=no
DR   Pfam; PF02769; AIRS_C; 1; trigger=no
DR   NCBIfam; TIGR01736; FGAM_synth_II; 1; trigger=no
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KW   ATP-binding
KW   Cytoplasm
KW   Ligase
KW   Metal-binding
KW   Magnesium
KW   Nucleotide-binding
KW   Purine biosynthesis
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GO   GO:0000287; F:magnesium ion binding
GO   GO:0005524; F:ATP binding
GO   GO:0004642; F:phosphoribosylformylglycinamidine synthase activity
GO   GO:0006189; P:'de novo' IMP biosynthetic process
GO   GO:0005737; C:cytoplasm
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FT   From: PURL_THEMA (Q9X0X3)
FT   BINDING         71..74
FT                   /ligand="substrate"
FT   Condition: S-H-N-H
FT   BINDING         280..282
FT                   /ligand="substrate"
FT   Condition: E-S-Q
FT   ACT_SITE        32
FT   Condition: H
FT   ACT_SITE        72
FT                   /note="Proton acceptor"
FT   Condition: H
FT   BINDING         70
FT                   /ligand="Mg(2+)"
FT                   /ligand_id="ChEBI:CHEBI:18420"
FT                   /ligand_label="1"
FT   Condition: E
FT   BINDING         94
FT                   /ligand="Mg(2+)"
FT                   /ligand_id="ChEBI:CHEBI:18420"
FT                   /ligand_label="2"
FT   Condition: D
FT   BINDING         236
FT                   /ligand="Mg(2+)"
FT                   /ligand_id="ChEBI:CHEBI:18420"
FT                   /ligand_label="2"
FT   Condition: D
FT   BINDING         478
FT                   /ligand="Mg(2+)"
FT                   /ligand_id="ChEBI:CHEBI:18420"
FT                   /ligand_label="1"
FT   Condition: N
FT   BINDING         35
FT                   /ligand="ATP"
FT                   /ligand_id="ChEBI:CHEBI:30616"
FT   Condition: Y
FT   BINDING         68
FT                   /ligand="ATP"
FT                   /ligand_id="ChEBI:CHEBI:30616"
FT   Condition: [KR]
FT   BINDING         93
FT                   /ligand="substrate"
FT   Condition: R
FT   BINDING         189
FT                   /ligand="substrate"
FT   Condition: R
FT   BINDING         208
FT                   /ligand="substrate"
FT   Condition: Q
FT   BINDING         442
FT                   /ligand="ATP"
FT                   /ligand_id="ChEBI:CHEBI:30616"
FT   Condition: [ND]
FT   BINDING         477
FT                   /ligand="ATP"
FT                   /ligand_id="ChEBI:CHEBI:30616"
FT   Condition: G
FT   BINDING         480
FT                   /ligand="substrate"
FT   Condition: S
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Size: 603-824;
Related: MF_00419;
Template: P12042; Q9X0X3; Q5SMH8;
Scope:
 Bacteria
 Archaea
Fusion:
 Nter: None
 Cter: None
Duplicate: None
Plasmid: None
Comments: FGAM synthase can be composed of a single polypeptide (large PurL, MF_00419),
 or it can be composed of three separate proteins: PurL (small PurL, MF_00420), PurQ (MF_00421)
 and PurS (MF_01926).
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# Revision 1.47 2023/06/01
//