title: Self-sufficient redox biotransformation of lignin-related benzoic acids with Aspergillus flavus.
abstract: Aromatic carboxylic acids are readily obtained from lignin in biomass processing facilities. However, efficient technologies for lignin valorization are missing. In this work, a microbial screening was conducted to find versatile biocatalysts capable of transforming several benzoic acids structurally related to lignin, employing vanillic acid as model substrate. The wild-type Aspergillus flavus growing cells exhibited exquisite selectivity towards the oxidative decarboxylation product, 2-methoxybenzene-1,4-diol. Interestingly, when assaying a set of structurally related substrates, the biocatalyst displayed the oxidative removal of the carboxyl moiety or its reduction to the primary alcohol whether electron withdrawing or donating groups were present in the aromatic ring, respectively. Additionally, A. flavus proved to be highly tolerant to vanillic acid increasing concentrations (up to 8 g/L), demonstrating its potential application in chemical synthesis. A. flavus growing cells were found to be efficient biotechnological tools to perform self-sufficient, structure-dependent redox reactions. To the best of our knowledge, this is the first report of a biocatalyst exhibiting opposite redox transformations of the carboxylic acid moiety in benzoic acid derivatives, namely oxidative decarboxylation and carboxyl reduction, in a structure-dependent fashion.
authors.affiliation: Area de Química Orgánica, Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, INTEQUI-CONICET, 5700, San Luis, Argentina.
authors.forename: Martín A
authors.initials: MA
authors.lastname: Palazzolo
authors.affiliation: Area de Química Orgánica, Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, INTEQUI-CONICET, 5700, San Luis, Argentina.|Laboratorio de Biología Molecular, Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, IMIBIO- SL CONICET, 5700, San Luis, Argentina.
authors.forename: María L
authors.initials: ML
authors.lastname: Mascotti
authors.affiliation: Laboratorio de Biotransformaciones, Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, 1876, Bernal, Argentina.
authors.forename: Elizabeth S
authors.initials: ES
authors.lastname: Lewkowicz
authors.affiliation: Area de Química Orgánica, Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, INTEQUI-CONICET, 5700, San Luis, Argentina. marcelakurina@gmail.com.
authors.forename: Marcela
authors.initials: M
authors.lastname: Kurina-Sanz
mesh_terms: D001231:Aspergillus flavus / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D001565:Benzoates / Q000378:metabolism* / Q000494:pharmacology; D001711:Biotransformation / Q000187:drug effects; D002396:Catechols / Q000378:metabolism; D006873:Hydroquinones / Q000378:metabolism; D008031:Lignin / Q000737:chemistry* / Q000378:metabolism*; D010084:Oxidation-Reduction / Q000187:drug effects; D014641:Vanillic Acid / Q000378:metabolism / Q000494:pharmacology
chemical_list: C000607138:2-methoxybenzene-1,4-diol; D001565:Benzoates; D002396:Catechols; D006873:Hydroquinones; D008031:Lignin; D014641:Vanillic Acid
keywords: Aspergillus flavus; Benzoic acids; Carboxyl reduction; Oxidative decarboxylation; Redox biotransformation