EC 1.2.1.70     
Accepted name: glutamyl-tRNA reductase
Reaction: L-glutamate 1-semialdehyde + NADP+ + tRNAGlu = L-glutamyl-tRNAGlu + NADPH + H+
Systematic name: L-glutamate-semialdehyde:NADP+ oxidoreductase (L-glutamyl-tRNAGlu-forming)
Comments: This enzyme forms part of the pathway for the biosynthesis of 5-aminolevulinate from glutamate, known as the C5 pathway. The route shown in the diagram is used in most eubacteria, and in all archaebacteria, algae and plants. However, in the α-proteobacteria, EC 2.3.1.37, 5-aminolevulinate synthase, is used in an alternative route to produce the product 5-aminolevulinate from succinyl-CoA and glycine. This route is found in the mitochondria of fungi and animals, organelles that are considered to be derived from an endosymbiotic α-proteobacterium. Although higher plants do not possess EC 2.3.1.37, the protistan Euglena gracilis possesses both the C5 pathway and EC 2.3.1.37.
References:
1.  von Wettstein, D., Gough, S. and Kannangara, C.G. Chlorophyll biosynthesis. Plant Cell 7 (1995) 1039–1057. [PMID: 12242396]
2.  Pontoppidan, B. and Kannangara, C.G. Purification and partial characterisation of barley glutamyl-tRNAGlu reductase, the enzyme that directs glutamate to chlorophyll biosynthesis. Eur. J. Biochem. 225 (1994) 529–537. [PMID: 7957167]
3.  Schauer, S., Chaturvedi, S., Randau, L., Moser, J., Kitabatake, M., Lorenz, S., Verkamp, E., Schubert, W.D., Nakayashiki, T., Murai, M., Wall, K., Thomann, H.-U., Heinz, D.W., Inokuchi, H, Söll, D. and Jahn, D. Escherichia coli glutamyl-tRNA reductase. Trapping the thioester intermediate. J. Biol. Chem. 277 (2002) 48657–48663. [PMID: 12370189]
[EC 1.2.1.70 created 2004]
 
 
EC 5.4.3.8     
Accepted name: glutamate-1-semialdehyde 2,1-aminomutase
Reaction: L-glutamate 1-semialdehyde = 5-aminolevulinate
Glossary: L-glutamate 1-semialdehyde = (S)-4-amino-5-oxopentanoate
Other name(s): glutamate-1-semialdehyde aminotransferase
Systematic name: (S)-4-amino-5-oxopentanoate 4,5-aminomutase
Comments: Requires pyridoxal phosphate.
References:
1.  Gough, S.P. and Kannangara, C.G. Biosynthesis of δ-aminolevulinate in greening barley leaves: glutamate 1-semialdehyde aminotransferase. Carlsberg Res. Commun. 43 (1978) 185–194.
[EC 5.4.3.8 created 1983]