In enzymology, a glutamate-1-semialdehyde 2,1-aminomutase is an enzyme that catalyzes the chemical reaction Hence, this enzyme has one substrate, L-glutamate-1-semialdehyde, and one product, 5-aminolevulinate. This enzyme belongs to the family of isomerases, specifically those intramolecular transferases transferring amino groups. The systematic name of this enzyme class is (S)-4-amino-5-oxopentanoate 4,5-aminomutase. This enzyme is also called glutamate-1-semialdehyde aminotransferase. This enzyme participates in porphyrin and chlorophyll biosynthesis. It employs one cofactor, pyridoxal phosphate.

Structural studies

As of late 2007, 10 structures have been solved for this class of enzymes, with PDB accession codes, , , , , , , , , and.