Annotation rule MF_01261
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General rule information [?]

Accession MF_01261
Dates 29-JUL-2005 (Created)
28-JAN-2011 (Last updated, Version 12)
Name CCA_bact_type1
Scope Bacteria; Proteobacteria

Propagated annotation [?]


Identifier, protein and gene names [?]

Identifier
CCA
Protein name
RecName: Full=Multifunctional CCA protein;
Includes:
RecName: Full=CCA-adding enzyme;
EC=2.7.7.72;
AltName: Full=CCA tRNA nucleotidyltransferase;
AltName: Full=tRNA CCA-pyrophosphorylase;
AltName: Full=tRNA adenylyl-/cytidylyl-transferase;
AltName: Full=tRNA nucleotidyltransferase;
AltName: Full=tRNA-NT;
Includes:
RecName: Full=2'-nucleotidase;
EC=3.1.3.-;
Includes:
RecName: Full=2',3'-cyclic phosphodiesterase;
EC=3.1.4.-;
Includes:
RecName: Full=Phosphatase;
EC=3.1.3.-;
Gene name
cca

Comments [?]

Function Catalyzes the addition and repair of the essential 3'-terminal CCA sequence in tRNAs without using a nucleic acid template. Adds these three nucleotides in the order of C, C, and A to the tRNA nucleotide-73, using CTP and ATP as substrates and producing inorganic pyrophosphate. Also shows phosphatase, 2'-nucleotidase and 2',3'-cyclic phosphodiesterase activities. These phosphohydrolase activities are probably involved in the repair of the tRNA 3'-CCA terminus degraded by intracellular RNases (By similarity).
Catalytic activity A tRNA precursor + 2 CTP + ATP = a tRNA with a 3' CCA end + 3 diphosphate.
Cofactor Magnesium for nucleotidyltransferase activity (By similarity).
Nickel for phosphatase activity (By similarity).
Subunit Monomer. Can also form homodimers and oligomers (By similarity).
Domain Comprises two domains: an N-terminal domain containing the nucleotidyltransferase activity and a C-terminal HD domain associated with both phosphodiesterase and phosphatase activities (By similarity).
Miscellaneous A single active site specifically recognizes both ATP and CTP and is responsible for their addition (By similarity).
Similarity Belongs to the tRNA nucleotidyltransferase/poly(A) polymerase family. Bacterial CCA-adding enzyme type 1 subfamily.

Keywords [?]


Gene Ontology [?]

GO:0000049; Molecular function: tRNA binding.
GO:0000166; Molecular function: nucleotide binding.
GO:0000287; Molecular function: magnesium ion binding.
GO:0004112; Molecular function: cyclic-nucleotide phosphodiesterase activity.
GO:0004810; Molecular function: tRNA adenylyltransferase activity.
GO:0005524; Molecular function: ATP binding.
GO:0016437; Molecular function: tRNA cytidylyltransferase activity.
GO:0016791; Molecular function: phosphatase activity.
GO:0001680; Biological process: tRNA 3'-terminal CCA addition.

Cross-references [?]

Pfam PF01966; HD; 1;
PF01743; PolyA_pol; 1;

Features [?]

From: CCA_ECOLI (P06961)
Key     From     To       Description   Tag   Condition   FTGroup
METAL     21     21       Magnesium (By similarity)     [DE]  
METAL     23     23       Magnesium (By similarity)     D  
BINDING     8     8       ATP or CTP; via amide nitrogen (By similarity)     G  
BINDING     11     11       ATP or CTP (By similarity)     R  
BINDING     91     91       ATP or CTP (By similarity)     R  
BINDING     137     137       ATP or CTP (By similarity)     R  
BINDING     140     140       ATP or CTP (By similarity)     R  

Additional information [?]

Size range 368-429 amino acids
Related rules MF_01262 (CCA)
Templates P06961 (CCA_ECOLI); Q7SIB1 (CCA_GEOSE): [Recover all]
Fusion None
Comments The CCA-adding enzyme family consists of 4 different subfamilies: 3 bacterial subfamilies (MF_01261, MF_01262 and MF_01263) and 1 archaeal subfamily (MF_01264). FT lines are propagated from B.stearothermophilus CCA-adding enzyme (type 3 subfamily, MF_01263) whose X-ray structure is known.