Biochemical characterization and substrate profiling of a reversible 2,3-dihydroxybenzoic acid decarboxylase for biocatalytic Kolbe-Schmitt reaction

Publication date: Available online 21 February 2018 Source:Enzyme and Microbial Technology Author(s): Xuemei Zhang, Jie Ren, Peiyuan Yao, Rui Gong, Min Wang, Qiaqing Wu, Dunming Zhu Reversible benzoic acid decarboxylases are versatile biocatalysts by taking advantage of both decarboxylation and carboxylation reactions, especially for the biocatalytic Kolbe-Schmitt reaction. In the course of developing a benzoic acid decarboxylase tool-box, a putative benzoic acid decarboxylase gene from Fusarium oxysporum was heterologously over-expressed in Escherichia coli, the recombinant protein was purified and characterized. The purified enzyme exhibited relatively high catalytic efficiencies for the decarboxylation of 2, 3-dihydroxybenzoic acid and carboxylation of catechol (k cat/K m = 2.03 × 102 and 1.88 mM−1 min−1, respectively), and thus characterized as 2, 3-dihydroxybenzoic acid decarboxylase (2, 3-DHBD_Fo). The enzyme also catalyzed the decarboxylation of various substituted salicylic acids with different groups at varied positions except 5-position and the carboxylation of phenol and the substituted phenols. In a preparative reaction, catechol was carboxylated into 2, 3-dihydroxybenoic acid with 95% conversion by adding dodecyldimethylbenzylammonium chloride into the reaction system, and the product was isolated in 72% yield. These results demonstrate that 2, 3-DHBD_Fo is a valuable addition to the benzoic acid decarboxylase tool-box with potential pra...
Source: Enzyme and Microbial Technology - Category: Biotechnology Source Type: research