Salicin is a notable phenolic glycoside derived from
plants including
Salix
and
Populus
genus and has multiple
biological activities such as anti-inflammatory and antiarthritic,
anticancer, and antiaging effects. In this work, we engineered production
of salicin from cheap renewable carbon resources in
Escherichia coli
(
E. coli
) by extending the shikimate pathway. We first investigated enzymes
synthesizing salicylate from chorismate. Subsequently, carboxylic
acid reductases (CARs) from different resources were screened to achieve
efficient reduction of salicylate. Third, glucosyltransferases from
different sources were selected for constructing cell factories of
salicin. The enzymes including salicylate synthase AmS from
Amycolatopsis methanolica
, carboxylic acid reductase
CARse from
Segniliparus rotundus,
and
glucosyltransferase UGT71L1 from
Populous trichocarpa
were overexpressed in a modified
E. coli
strain MG1655-U7. The engineered strain produced 912.3 ± 12.7
mg/L salicin in 72 h of fermentation. These results demonstrated the
production of salicin in a microorganism and laid significant foundation
for its commercialization for pharmaceutical and nutraceutical applications.