HAMAP

Accession	MF_01264
Dates	29-JUL-2005 (Created) 28-JAN-2011 (Last updated, Version 8)

Data class

Protein

Predictors

HAMAP; MF_01264; [distribution of match scores in UniProtKB];[seed alignment for MF_01264]

Names

CCA_arch

Identifier

CCA

Protein name

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;

Gene name

cca

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 (By similarity).

CATALYTIC ACTIVITY: A tRNA precursor + 2 CTP + ATP = a tRNA with a 3' CCA end + 3 diphosphate.

COFACTOR: Magnesium (By similarity).

SUBUNIT: Homodimer (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. Archaeal CCA-adding enzyme subfamily.

Pfam	PF01909; NTP_transf_2; 1; PF09249; tRNA_NucTransf2; 1;
PIRSF	PIRSF005335; CCA_arch; 1;
TIGRFAMs	TIGR03671; Cca_archaeal; 1;

ATP-binding, Magnesium, Metal-binding, Nucleotide-binding, Nucleotidyltransferase, RNA repair, RNA-binding, Transferase, tRNA processing.

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

From: CCA_ARCFU (O28126)
Key		From		To		Description		Condition		FTGroup
METAL		59		59		Magnesium (By similarity)		[DE]
METAL		61		61		Magnesium (By similarity)		D
METAL		110		110		Magnesium (By similarity)		[DE]
BINDING		47		47		ATP or CTP (By similarity)		S
BINDING		50		50		ATP or CTP (By similarity)		[RK]
BINDING		133		133		ATP or CTP (By similarity)		H
BINDING		152		152		ATP or CTP (By similarity)		K
BINDING		161		161		ATP or CTP (By similarity)		Y

Size range:	392-485 amino acids
Related UniRules:	None
Template:	O28126 (CCA_ARCFU); P77978 (CCA_SULSH); Q58511 (CCA_METJA): [Recover all]
Scope:	Archaea
Fusion:	Nter: None; Cter: None
Duplicate:	None
Plasmid encoded:	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).