HAMAP

Accession	MF_00087
Dates	1-JUN-2001 (Created) 6-OCT-2011 (Last updated, Version 39)

Data class

Protein

Predictors

HAMAP; MF_00087; [distribution of match scores in UniProtKB];[seed alignment for MF_00087]

Names

Glu-tRNA_reductase

Identifier

HEM1

Protein name

RecName: Full=Glutamyl-tRNA reductase; Short=GluTR; EC=1.2.1.70;

Gene name

hemA

FUNCTION: Catalyzes the NADPH-dependent reduction of glutamyl-tRNA(Glu) to glutamate 1-semialdehyde (GSA) (By similarity).

CATALYTIC ACTIVITY: L-glutamate 1-semialdehyde + NADP(+) + tRNA(Glu) = L-glutamyl-tRNA(Glu) + NADPH.

PATHWAY: Porphyrin metabolism; protoporphyrin-IX biosynthesis; 5-aminolevulinate from L-glutamyl-tRNA(Glu): step 1/2.

PATHWAY: Porphyrin biosynthesis; chlorophyll biosynthesis.

SUBUNIT: Homodimer (By similarity).

SUBCELLULAR LOCATION: Plastid, chloroplast.

DOMAIN: Possesses an unusual extended V-shaped dimeric structure with each monomer consisting of three distinct domains arranged along a curved 'spinal' alpha-helix. The N-terminal catalytic domain specifically recognizes the glutamate moiety of the substrate. The second domain is the NADPH-binding domain, and the third C-terminal domain is responsible for dimerization (By similarity).

MISCELLANEOUS: During catalysis, the active site Cys acts as a nucleophile attacking the alpha-carbonyl group of tRNA-bound glutamate with the formation of a thioester intermediate between enzyme and glutamate, and the concomitant release of tRNA(Glu). The thioester intermediate is finally reduced by direct hydride transfer from NADPH, to form the product GSA (By similarity).

SIMILARITY: Belongs to the glutamyl-tRNA reductase family.

PROSITE	PS00747; GLUTR; 1;
Pfam	PF01488; Shikimate_DH; 1;
TIGRFAMs	TIGR01035; HemA; 1;

Porphyrin biosynthesis.

Chlorophyll biosynthesis.

Oxidoreductase, NADP.

GO:0008883; Molecular function: glutamyl-tRNA reductase activity.

GO:0015995; Biological process: chlorophyll biosynthetic process.

GO:0006779; Biological process: porphyrin-containing compound biosynthetic process.

GO:0009507; Cellular component: chloroplast.

From: HEM1_METKA (Q9UXR8)
Key		From		To		Description		Condition		FTGroup
NP_BIND		174		179		NADP (By similarity)
REGION		47		50		Substrate binding (By similarity)		T-C-x-R
REGION		99		101		Substrate binding (By similarity)		[ED]-x-[EDQ]
ACT_SITE		48		48		Nucleophile (By similarity)		C
BINDING		94		94		Substrate (By similarity)		S
BINDING		105		105		Substrate (By similarity)		Q
SITE (Optional)		84		84		Important for activity (By similarity)		H

Size range:	329-497 amino acids
Related UniRules:	None
Template:	P0A6X1 (HEM1_ECOLI); Q9UXR8 (HEM1_METKA); P28462 (HEM1_CHLP8); P42809 (HEM1_METTM); P28463 (HEM1_SYNY3); Q59292 (HEM1_CLOJO); P42808 (HEM1_XANCH): [Recover all]
Scope:	Bacteria Archaea Plastid
Fusion:	Nter: None; Cter: None
Duplicate:	in KORVE, ANADE, ANADF, CLOPH, FLAJ1, NOCSJ, PYRAR, PYRCJ
Plasmid encoded:	None
Comments:	STRAW and STRCO have an internal inserted domains of about 120 residues; sequence not included in alignment. Highly divergent CLOJO; sequence not included in alignment SORC5 has a long C-terminus; not included in alignment