Whole cell biocatalyst for the preparation of nitro compounds from amines

LUCAS MARCHESANO; ABIGAIL M. STRICKER; ADOLFO M. IRIBARREN; ELIZABETH S. LEWKOWICZ; NOBILE, MATIAS

Jornada; Biocatalysis Open day; 2020

Federacion Europea de Biotecnología

To date, several natural products containing nitro groups have been identified, many of them of huge therapeutic and commercial importance such as the bioactive agents aureothin and azomycin. The formation of dangerous by-products , in addition to the low yields and stereoselectivity involved in the synthesis of nitro derivatives, demand the development of new strategies. In this sense, several N-oxygenases from the genus Streptomyces have been isolated and studied. These kinds of reactions are characterized by the sequential addition of oxygen atoms into an amine, which is typically catalyzed by a non-heme di-iron monooxygenase like AurF from S. venezuelae. However these reactions are powered by the cofactor NADH, so its industrial application is economically limited. In this work the use of phylogenetically and in silico related Streptomyces strains as whole cells is proposed, which when stressed in a non-specific way, proved to be a useful biocatalyst to prepare nitro compounds from aromatic amines, avoiding the use of expensive energetic cofactors. The best results were obtained using co-cultures of bacterial strains capable of being natural competitors of Streptomyces such as Bacillus cereus. Conversions up to 45% were achieved for the N-oxygenation of p-aminobenzoic acid using S. griseus as whole cell biocatalyst.