Fecha de publicación: 09/12/2021 Fuente: WIPO "apis cerana" Described herein are engineered cells, enzymes, methods of use, and bee bread incorporating engineered cells and enzymes as described herein. In certain aspects, described herein are a bacterium containing therein one or more stably-expressing expression vectors for exogenous expression of one or more recombinant carboxylesterase enzymes or oxalate decarboxylase enzymes, thereby providing the engineered cell an exogenous pathway for hydrolyzing ester bonds or removing a carboxyl group. Engineered cells and recombinant enzymes as described herein can be incorporated into bee bread to be fed to a member of the Apidae family of bees or of the Apis or Bombus genus. In additional aspects, such bacteria can also be selected and amplified from the milieu of the hive microorganisms and in some cases they can be molecularly bred to enhance their metabolic capabilities without genetic engineering.