Advances in genome and metabolic pathway engineering have enabled large combinatorial libraries of mutant microbial hosts for chemical biosynthesis. Despite these advances, strain development is often limited by the lack of high throughput functional assays for effective library screening. Recent synthetic biology efforts have engineered microbes that synthesize acetyl and acyl esters and many yeasts naturally produce esters to significant titers. Short and medium chain volatile esters have value as fragrance and flavor compounds, while long chain acyl esters are potential replacements for diesel fuel. Here, we developed a biotechnology method for the rapid screening of microbial ester biosynthesis. Using a colorimetric reaction scheme, esters extracted from fermentation broth were quantitatively converted to a ferric hydroxamate complex with strong absorbance at 520 nm. The assay was validated for ethyl acetate, ethyl butyrate, isoamyl acetate, ethyl hexanoate, and ethyl octanoate, and achieved a z‐factor of 0.77. Screening of ethyl acetate production from a combinatorial library of four
This content will become publicly available on May 1, 2025
- PAR ID:
- 10504521
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Metabolic Engineering
- Volume:
- 83
- Issue:
- C
- ISSN:
- 1096-7176
- Page Range / eLocation ID:
- 102 to 109
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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