title: Metabolic engineering of Corynebacterium glutamicum for the production of itaconate.
abstract: The capability of Corynebacterium glutamicum for glucose-based synthesis of itaconate was explored, which can serve as building block for production of polymers, chemicals, and fuels. C. glutamicum was highly tolerant to itaconate and did not metabolize it. Expression of the Aspergillus terreus CAD1 gene encoding cis-aconitate decarboxylase (CAD) in strain ATCC13032 led to the production of 1.4mM itaconate in the stationary growth phase. Fusion of CAD with the Escherichia coli maltose-binding protein increased its activity and the itaconate titer more than two-fold. Nitrogen-limited growth conditions boosted CAD activity and itaconate titer about 10-fold to values of 1440 mU mg(-1) and 30 mM. Reduction of isocitrate dehydrogenase activity via exchange of the ATG start codon to GTG or TTG resulted in maximal itaconate titers of 60 mM (7.8 g l(-1)), a molar yield of 0.4 mol mol(-1), and a volumetric productivity of 2.1 mmol l(-1) h(-1).
authors.affiliation: IBG-1: Biotechnology, Institute of Bio- and Geosciences, Forschungszentrum Jülich, 52425 Jülich, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Otten
authors.affiliation: IBG-1: Biotechnology, Institute of Bio- and Geosciences, Forschungszentrum Jülich, 52425 Jülich, Germany. Electronic address: m.brocker@fz-juelich.de.
authors.forename: Melanie
authors.initials: M
authors.lastname: Brocker
authors.affiliation: IBG-1: Biotechnology, Institute of Bio- and Geosciences, Forschungszentrum Jülich, 52425 Jülich, Germany. Electronic address: m.bott@fz-juelich.de.
authors.forename: Michael
authors.initials: M
authors.lastname: Bott
mesh_terms: D001230:Aspergillus / Q000201:enzymology / Q000235:genetics; D002262:Carboxy-Lyases / Q000096:biosynthesis / Q000235:genetics; D048230:Corynebacterium glutamicum / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000096:biosynthesis / Q000235:genetics; D005656:Fungal Proteins / Q000096:biosynthesis / Q000235:genetics; D058619:Maltose-Binding Proteins / Q000096:biosynthesis / Q000235:genetics; D060847:Metabolic Engineering / Q000379:methods*; D013386:Succinates / Q000378:metabolism*
chemical_list: D029968:Escherichia coli Proteins; D005656:Fungal Proteins; D058619:Maltose-Binding Proteins; D013386:Succinates; D002262:Carboxy-Lyases; C018742:aconitate decarboxylase; C005229:itaconic acid
keywords: Aconitase; Cis-aconitate decarboxylase; Corynebacterium glutamicum; Isocitrate dehydrogenase; MalE fusion protein; Nitrogen-limitation