Siderophores, such as enterobactin (Ent), are small molecules that can be selectively imported into bacteria along with iron by cognate transporters. Siderophore conjugates are thus a promising strategy for delivering functional reagents into bacteria. In this work, we present an easy-to-perform, one-pot chemoenzymatic synthesis of functionalized monoglucosylated enterobactin (MGE). When functionalized MGE is conjugated to a rhodamine fluorophore, which affords RhB-Glc-Ent, it can selectively label Gram-negative bacteria that utilize Ent, including some E. coli strains and P. aeruginosa. V. cholerae, a bacterium that utilizes linearized Ent, can also be weakly targeted. Moreover, the targeting is effective under iron-limiting but not iron-rich conditions. Our results suggest that the RhB-Glc-Ent probe is sensitive not only to the bacterial strain but also to the iron condition in the environment.

Siderophores,s uch as enterobactin (Ent), are small molecules that can be selectively imported into bacteria along with iron by cognate transporters.S iderophore conjugates are thus apromising strategy for delivering functional reagents into bacteria. In this work, we present an easy-to-perform, one-pot chemoenzymatic synthesis of functionalizedm onoglucosylated enterobactin (MGE). When functionalizedM GE is conjugated to ar hodamine fluorophore,w hich affords RhB-Glc-Ent, it can selectively label Gram-negative bacteria that utilize Ent, including some E. coli strains and P. aeruginosa. V. cholerae,abacterium that utilizes linearized Ent, can also be weakly targeted. Moreover,the targeting is effective under ironlimiting but not iron-rich conditions.O ur results suggest that the RhB-Glc-Ent probe is sensitive not only to the bacterial strain but also to the iron condition in the environment.Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: http://dx.