Flux Balance Analysis for Media Optimization and Genetic Targets to Improve Heterologous Siderophore Production.

Siderophores are small molecule metal chelators secreted in sparse quantities by their native microbial hosts but can be engineered for enhanced production from heterologous hosts like Escherichia coli. These molecules have been proved to be capable of binding heavy metals of commercial and/or environmental interest. In this work, we incorporated, as needed, the appropriate pathways required to produce several siderophores (anguibactin, vibriobactin, bacillibactin, pyoverdine, and enterobactin) into the base E.

Yersiniabactin metal binding characterization and removal of nickel from industrial wastewater.

Yersiniabactin (Ybt) is a metal-binding natural product that has been re-purposed for water treatment. The early focus of this study was the characterization of metal binding breadth attributed to Ybt. Using LC-MS analysis of water samples exposed to aqueous and surface-localized Ybt, quantitative assessment of binding was completed with metals that included Pd , Mg , and Zn .

Increased production of yersiniabactin and an anthranilate analog through media optimization.

Yersiniabactin (Ybt) is a mixed nonribosomal peptide-polyketide natural product that binds a wide range of metals with the potential to impact processes requiring metal retrieval and removal. In this work, we substantially improved upon the heterologous production of Ybt and an associated anthranilate analog through systematic screening and optimization of culture medium components. Specifically, a Plackett-Burman design-of-experiments methodology was used to screen 22 components and to determine those contributing most to siderophore production.

E. coli metabolic engineering for gram scale production of a plant-based anti-inflammatory agent.

In this report, the heterologous production of salicylate (SA) is the basis for metabolic extension to salicylate 2-O-β-d-glucoside (SAG), a natural product implicated in plant-based defense mechanisms. Production was optimized through a combination of metabolic engineering, gene expression variation, and co-culture design. When combined, SA and SAG production titers reached ~0.