AC   MF_01850;
DC   Protein; auto
TR   HAMAP; MF_01850; -; 1; level=0
XX
Names: TtcA
XX
ID   TTCA
DE   RecName: Full=tRNA-cytidine(32) 2-sulfurtransferase;
DE            EC=2.8.1.-;
DE   AltName: Full=Two-thiocytidine biosynthesis protein A;
DE   AltName: Full=tRNA 2-thiocytidine biosynthesis protein TtcA;
GN   Name=ttcA;
XX
CC   -!- FUNCTION: Catalyzes the ATP-dependent 2-thiolation of cytidine in
CC       position 32 of tRNA, to form 2-thiocytidine (s(2)C32). The sulfur atoms
CC       are provided by the cysteine/cysteine desulfurase (IscS) system.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=AH2 + ATP + cytidine(32) in tRNA + S-sulfanyl-L-cysteinyl-
CC         [cysteine desulfurase] = 2-thiocytidine(32) in tRNA + A + AMP +
CC         diphosphate + H(+) + L-cysteinyl-[cysteine desulfurase];
CC         Xref=Rhea:RHEA:57048, Rhea:RHEA-COMP:10288, Rhea:RHEA-COMP:12157,
CC         Rhea:RHEA-COMP:12158, Rhea:RHEA-COMP:14821, ChEBI:CHEBI:13193,
CC         ChEBI:CHEBI:15378, ChEBI:CHEBI:17499, ChEBI:CHEBI:29950,
CC         ChEBI:CHEBI:30616, ChEBI:CHEBI:33019, ChEBI:CHEBI:61963,
CC         ChEBI:CHEBI:82748, ChEBI:CHEBI:141453, ChEBI:CHEBI:456215;
CC       PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:57049;
CC   -!- COFACTOR:
CC       Name=[4Fe-4S] cluster; Xref=ChEBI:CHEBI:49883;
CC       Note=Binds 1 [4Fe-4S] cluster per subunit. The cluster is chelated by
CC       three Cys residues, the fourth Fe has a free coordination site that may
CC       bind a sulfur atom transferred from the persulfide of IscS
CC   -!- COFACTOR:
CC       Name=Mg(2+); Xref=ChEBI:CHEBI:18420;
CC   -!- PATHWAY: tRNA modification.
CC   -!- SUBUNIT: Homodimer.
CC   -!- SUBCELLULAR LOCATION: Cytoplasm.
CC   -!- MISCELLANEOUS: The thiolation reaction likely consists of two steps: a
CC       first activation step by ATP to form an adenylated intermediate of the
CC       target base of tRNA, and a second nucleophilic substitution step of the
CC       sulfur (S) atom supplied by the hydrosulfide attached to the Fe-S
CC       cluster.
CC   -!- SIMILARITY: Belongs to the TtcA family.
XX
DR   Pfam; PF01171; ATP_bind_3; 1; trigger=no
DR   PIRSF; PIRSF004976; ATPase_YdaO; 1; trigger=no
XX
KW   4Fe-4S
KW   ATP-binding
KW   Cytoplasm
KW   Iron
KW   Iron-sulfur
KW   Magnesium
KW   Metal-binding
KW   Nucleotide-binding
KW   RNA-binding
KW   Transferase
KW   tRNA processing
KW   tRNA-binding
XX
GO   GO:0000287; F:magnesium ion binding
GO   GO:0005524; F:ATP binding
GO   GO:0016783; F:sulfurtransferase activity
GO   GO:0051539; F:4 iron, 4 sulfur cluster binding
GO   GO:0034227; P:tRNA thio-modification
GO   GO:0005737; C:cytoplasm
XX
FT   From: TTCA_ECOLI (P76055)
FT   MOTIF           47..52
FT                   /note="PP-loop motif"
FT   Condition: S-G-G-K-D-S
FT   BINDING         122
FT                   /ligand="[4Fe-4S] cluster"
FT                   /ligand_id="ChEBI:CHEBI:49883"
FT   Group: 1; Condition: C
FT   BINDING         125
FT                   /ligand="[4Fe-4S] cluster"
FT                   /ligand_id="ChEBI:CHEBI:49883"
FT   Group: 1; Condition: C
FT   BINDING         213
FT                   /ligand="[4Fe-4S] cluster"
FT                   /ligand_id="ChEBI:CHEBI:49883"
FT   Group: 1; Condition: C
XX
Size: 251-381;
Related: None;
Template: P76055; Q8ZP88;
Scope:
 Bacteria; Bacteroidota
 Bacteria; Acaryochloris
 Bacteria; Deinococcota
 Bacteria; Pseudomonadota
Fusion:
 Nter: None
 Cter: None
Duplicate: in FRAP2, FRAT1, FRATF, FRATH, FRATN, FRATO, FRATT, FRATW, SHEB5
Plasmid: in SHEB5
Comments: None
XX
# Revision 1.16 2023/02/17
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