Reaction: (1) D-galactaro-1,4-lactone = 5-dehydro-4-deoxy-D-glucarate
(2) D-glucaro-1,4-lactone = 5-dehydro-4-deoxy-D-glucarate
Other name(s): GCI
Systematic name: D-galactaro-1,4-lactone lyase (ring-opening)
Comments: The enzyme, characterized from the bacterium Agrobacterium fabrum strain C58, is involved in degradation of D-galacturonate and D-glucuronate. Activity with D-galactaro-1,4-lactone is 4-fold higher than with D-glucaro-1,4-lactone.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number:
1. Andberg, M., Maaheimo, H., Boer, H., Penttila, M., Koivula, A. and Richard, P. Characterization of a novel Agrobacterium tumefaciens galactarolactone cycloisomerase enzyme for direct conversion of D-galactarolactone to 3-deoxy-2-keto-L-threo-hexarate. J. Biol. Chem. 287 (2012) 17662-17671. [PMID: 22493433]
2. Bouvier, J.T., Groninger-Poe, F.P., Vetting, M., Almo, S.C. and Gerlt, J.A. Galactaro δ-lactone isomerase: lactone isomerization by a member of the amidohydrolase superfamily. Biochemistry 53 (2014) 614-616. [PMID: 24450804]