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Annotation rule MF_01850
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General rule information [?]

Accession MF_01850
Dates 15-JUL-2008 (Created)
9-OCT-2017 (Last updated, Version 9)
Name TtcA
Scope Bacteria; Bacteroidetes
Bacteria; Acaryochloris
Bacteria; Deinococcus-Thermus
Bacteria; Proteobacteria
Templates P76055 (TTCA_ECOLI); Q8ZP88 (TTCA_SALTY): [Recover all]

Propagated annotation [?]

Identifier, protein and gene names [?]

Protein name
RecName: Full=tRNA-cytidine(32) 2-sulfurtransferase;
AltName: Full=Two-thiocytidine biosynthesis protein A;
AltName: Full=tRNA 2-thiocytidine biosynthesis protein TtcA;
Gene name

Comments [?]

Function Catalyzes the ATP-dependent 2-thiolation of cytidine in position 32 of tRNA, to form 2-thiocytidine (s(2)C32). The sulfur atoms are provided by the cysteine/cysteine desulfurase (IscS) system.
Cofactor [4Fe-4S] cluster
Note: Binds 1 [4Fe-4S] cluster per subunit. The cluster is chelated by three Cys residues, the fourth Fe has a free coordination site that may bind a sulfur atom transferred from the persulfide of IscS
Pathway tRNA modification.
Subunit Homodimer.
Subcellular location Cytoplasm.
Miscellaneous The thiolation reaction likely consists of two steps: a first activation step by ATP to form an adenylated intermediate of the target base of tRNA, and a second nucleophilic substitution step of the sulfur (S) atom supplied by the hydrosulfide attached to the Fe-S cluster.
Similarity Belongs to the TtcA family.

Keywords [?]

Gene Ontology [?]

GO:0000287; Molecular function: magnesium ion binding.
GO:0005524; Molecular function: ATP binding.
GO:0016783; Molecular function: sulfurtransferase activity.
GO:0051539; Molecular function: 4 iron, 4 sulfur cluster binding.
GO:0034227; Biological process: tRNA thio-modification.
GO:0005737; Cellular component: cytoplasm.

Cross-references [?]

Pfam PF01171; ATP_bind_3; 1;
PIRSF PIRSF004976; ATPase_YdaO; 1;

Features [?]

From: TTCA_ECOLI (P76055)
Key     From     To       Description   Tag   Condition   FTGroup
MOTIF     47     52       PP-loop motif     S-G-G-K-D-S  
METAL     122     122       Iron-sulfur (4Fe-4S)     C   1
METAL     125     125       Iron-sulfur (4Fe-4S)     C   1
METAL     213     213       Iron-sulfur (4Fe-4S)     C   1

Additional information [?]

Size range 251-381 amino acids
Related rules None
Fusion None