Reaction: (2S,3S)-2-methylcitrate = 2-methyl-trans-aconitate + H2O
Glossary: (2S,3S)-2-methylcitrate = (2S,3S)-2-hydroxybutane-1,2,3-tricarboxylate
2-methyl-trans-aconitate = (2E)-but-2-ene-1,2,3-tricarboxylate
Systematic name: (2S,3S)-2-hydroxybutane-1,2,3-tricarboxylate hydro-lyase (2-methyl-trans-aconitate forming)
Comments: Catalyses the dehydration of (2S,3S)-2-methylcitrate, forming the trans isomer of 2-methyl-aconitate (unlike EC 4.2.1.79, which forms only the cis isomer). Part of a propionate degradation pathway. The enzyme from Shewanella oneidensis can also accept citrate and cis-aconitate, but activity with (2S,3S)-2-methylcitrate was approximately 2.5-fold higher. 2-methylisocitrate and isocitrate were not substrates [1]. An iron-sulfur protein.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:
References:
1. Grimek, T.L. and Escalante-Semerena, J.C. The acnD genes of Shewenella oneidensis and Vibrio cholerae encode a new Fe/S-dependent 2-methylcitrate dehydratase enzyme that requires prpF function in vivo. J. Bacteriol. 186 (2004) 454-462. [PMID: 14702315]