Protein
Isopropylmalate/citramalate isomerase large subunit
Organism
Methanocaldococcus jannaschii (strain ATCC 43067 / DSM 2661 / JAL-1 / JCM 10045 / NBRC 100440)
Function
Enzyme with broad specificity that catalyzes reversible hydroxyacid isomerizations via dehydration/hydration reactions. Catalyzes the isomerization between 2-isopropylmalate and 3-isopropylmalate, via the formation of 2-isopropylmaleate, a step involved in leucine biosynthesis. Catalyzes the isomerization between 2-methylmalate and 3-methylmalate, via the formation of 2-methylmaleate (citraconate), a step involved in isoleucine biosynthesis. Also displays malease activity, i.e. catalyzes the hydration of maleate to form (R)-malate.
Similarity
Belongs to the aconitase/IPM isomerase family. LeuC type 2 subfamily.
Sequence
MGMTIVEKILAKASGKKEVSPGDIVMANIDVAMVHDITGPLTVNTLKEYGIEKVWNPEKIVILFDHQVPADSIKAAENHILMRKFVKEQGIKYFYDIREGVCHQVLPEKGHVAPGEVVVGADSHTCTHGAFGAFATGIGSTDMAHVFATGKLWFKVPETIYFNITGDLQPYVTSKDVILSIIGEVGVDGATYKACQFGGETVKKMSIASRMTMTNMAIEMGGKTGIIEPDEKTIQYVKEAMKKHGTERPFEVIKGDEDAEFAEVYEIEADKIEPVFACPHNVDNVKQAREVAGKPIDQVFIGSCTNGRLEDLRMAIKIIEKHGGIADDVRVVVTPASREEYLKALKEGIIEKFLKYGCVVTNPSCSACMGSLYGVLGPGEVCVSTSNRNFRGRQGSLEAEIYLASPITAAACAVKGELVDPRDL