title: Heterologous production and characterization of a chlorogenic acid esterase from Ustilago maydis with a potential use in baking.
abstract: Ustilago maydis, an edible mushroom growing on maize (Zea mays), is consumed as the food delicacy huitlacoche in Mexico. A chlorogenic acid esterase from this basidiomycete was expressed in good yields cultivating the heterologous host Pichia pastoris on the 5L bioreactor scale (reUmChlE; 45.9UL(-1)). In contrast to previously described chlorogenic acid esterases, the reUmChlE was also active towards feruloylated saccharides. The enzyme preferred substrates with the ferulic acid esterified to the O-5 position of arabinose residues, typical of graminaceous monocots, over the O-2 position of arabinose or the O-6 position of galactose residues. Determination of kcat/Km showed that the reUmChlE hydrolyzed chlorogenic acid 18-fold more efficiently than methyl ferulate, p-coumarate or caffeate. Phenolic acids were released by reUmChlE from natural substrates, such as destarched wheat bran, sugar beet pectin and coffee pulp. Treatment of wheat dough using reUmChlE resulted in a noticeable softening indicating a potential application of the enzyme in bakery and confectionery.
authors.affiliation: Institut für Lebensmittelchemie, Leibniz Universität Hannover, Callinstraße 5, 30167 Hannover, Germany. Electronic address: annabel.nieter@lci.uni-hannover.de.
authors.forename: Annabel
authors.initials: A
authors.lastname: Nieter
authors.affiliation: Institut für Lebensmittelchemie, Leibniz Universität Hannover, Callinstraße 5, 30167 Hannover, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Kelle
authors.affiliation: Institut für Lebensmittelchemie, Leibniz Universität Hannover, Callinstraße 5, 30167 Hannover, Germany.
authors.forename: Meike
authors.initials: M
authors.lastname: Takenberg
authors.affiliation: Institut für Lebensmittelchemie, Leibniz Universität Hannover, Callinstraße 5, 30167 Hannover, Germany.
authors.forename: Diana
authors.initials: D
authors.lastname: Linke
authors.affiliation: Institut für Angewandte Biowissenschaften, Karlsruher Institut für Technologie (KIT), Adenauerring 20A, 76131 Karlsruhe, Germany.
authors.forename: Mirko
authors.initials: M
authors.lastname: Bunzel
authors.affiliation: SternEnzym GmbH & Co. KG, Kurt-Fischer-Straße 55, 22926 Ahrensburg, Germany.
authors.forename: Lutz
authors.initials: L
authors.lastname: Popper
authors.affiliation: Institut für Lebensmittelchemie, Leibniz Universität Hannover, Callinstraße 5, 30167 Hannover, Germany.
authors.forename: Ralf G
authors.initials: RG
authors.lastname: Berger
mesh_terms: D002265:Carboxylic Ester Hydrolases / Q000378:metabolism*; D002726:Chlorogenic Acid / Q000378:metabolism*; D003296:Cooking; D004043:Dietary Fiber / Q000378:metabolism*; D006868:Hydrolysis; D062385:Hydroxybenzoates / Q000378:metabolism*; D008800:Mexico; D010843:Pichia / Q000201:enzymology*; D014588:Ustilago / Q000201:enzymology*
chemical_list: D004043:Dietary Fiber; D062385:Hydroxybenzoates; D002726:Chlorogenic Acid; D002265:Carboxylic Ester Hydrolases; C025374:chlorogenic acid esterase; C017616:phenolic acid
keywords: Baking; Basidiomycete; Chlorogenic acid; Coffee pulp; Esterase; Feruloylated saccharides; Heterologous expression; Pichia pastoris